All done

2023-02-28 20:57:21 +07:00 · 2023-02-28 20:57:21 +07:00 · 387f10b920
commit 387f10b920
parent 6d3ab691fb
82 changed files with 2916 additions and 0 deletions
--- a/app/.gitignore
+++ b/app/.gitignore
@ -0,0 +1 @@
+/build
--- a/app/build.gradle
+++ b/app/build.gradle
@ -0,0 +1,70 @@
+plugins {
+    id 'com.android.application'
+    id 'org.jetbrains.kotlin.android'
+    id 'kotlin-kapt'
+}
+
+android {
+    namespace 'xyz.nuark.pomslab1'
+    compileSdk 33
+
+    defaultConfig {
+        applicationId "xyz.nuark.pomslab1"
+        minSdk 24
+        targetSdk 33
+        versionCode 1
+        versionName "1.0"
+
+        vectorDrawables.useSupportLibrary = true
+
+        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
+    }
+
+    signingConfigs {
+        release {
+            def props = new Properties()
+            file("signing.properties").withInputStream { props.load(it) }
+
+            storeFile file(props.RELEASE_STORE_FILE)
+            storePassword props.RELEASE_STORE_PASSWORD
+            keyAlias props.RELEASE_KEY_ALIAS
+            keyPassword props.RELEASE_KEY_PASSWORD
+
+            v1SigningEnabled true
+            v2SigningEnabled true
+        }
+    }
+    buildTypes {
+        release {
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
+            signingConfig signingConfigs.release
+        }
+    }
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_8
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
+    kotlinOptions {
+        jvmTarget = '1.8'
+    }
+    buildFeatures {
+        viewBinding true
+        dataBinding true
+    }
+}
+
+dependencies {
+    implementation 'androidx.core:core-ktx:1.9.0'
+    implementation 'androidx.appcompat:appcompat:1.6.1'
+    implementation 'com.google.android.material:material:1.8.0'
+    implementation 'androidx.constraintlayout:constraintlayout:2.1.4'
+    implementation "androidx.activity:activity-ktx:1.6.1"
+    implementation "androidx.fragment:fragment-ktx:1.5.5"
+    implementation "androidx.room:room-runtime:2.5.0"
+    annotationProcessor "androidx.room:room-compiler:2.5.0"
+    kapt "androidx.room:room-compiler:2.5.0"
+    testImplementation 'junit:junit:4.13.2'
+    androidTestImplementation 'androidx.test.ext:junit:1.1.5'
+    androidTestImplementation 'androidx.test.espresso:espresso-core:3.5.1'
+}
--- a/app/proguard-rules.pro
+++ b/app/proguard-rules.pro
@ -0,0 +1,21 @@
+# Add project specific ProGuard rules here.
+# You can control the set of applied configuration files using the
+# proguardFiles setting in build.gradle.
+#
+# For more details, see
+#   http://developer.android.com/guide/developing/tools/proguard.html
+
+# If your project uses WebView with JS, uncomment the following
+# and specify the fully qualified class name to the JavaScript interface
+# class:
+#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
+#   public *;
+#}
+
+# Uncomment this to preserve the line number information for
+# debugging stack traces.
+#-keepattributes SourceFile,LineNumberTable
+
+# If you keep the line number information, uncomment this to
+# hide the original source file name.
+#-renamesourcefileattribute SourceFile
--- a/app/src/androidTest/java/xyz/nuark/pomslab1/ExampleInstrumentedTest.kt
+++ b/app/src/androidTest/java/xyz/nuark/pomslab1/ExampleInstrumentedTest.kt
@ -0,0 +1,24 @@
+package xyz.nuark.pomslab1
+
+import androidx.test.platform.app.InstrumentationRegistry
+import androidx.test.ext.junit.runners.AndroidJUnit4
+
+import org.junit.Test
+import org.junit.runner.RunWith
+
+import org.junit.Assert.*
+
+/**
+ * Instrumented test, which will execute on an Android device.
+ *
+ * See [testing documentation](http://d.android.com/tools/testing).
+ */
+@RunWith(AndroidJUnit4::class)
+class ExampleInstrumentedTest {
+    @Test
+    fun useAppContext() {
+        // Context of the app under test.
+        val appContext = InstrumentationRegistry.getInstrumentation().targetContext
+        assertEquals("xyz.nuark.pomslab1", appContext.packageName)
+    }
+}
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@ -0,0 +1,59 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools">
+
+    <application
+        android:name=".PomsApp"
+        android:allowBackup="true"
+        android:dataExtractionRules="@xml/data_extraction_rules"
+        android:fullBackupContent="@xml/backup_rules"
+        android:icon="@mipmap/ic_launcher"
+        android:label="@string/app_name"
+        android:supportsRtl="true"
+        android:theme="@style/Theme.PomsLab1"
+        tools:targetApi="31">
+        <activity
+            android:name=".view.activities.GraphicsActivity"
+            android:exported="false" />
+        <activity
+            android:name=".view.activities.LinkerActivity"
+            android:exported="true">
+            <intent-filter>
+                <action android:name="android.intent.action.VIEW" />
+
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.BROWSABLE" />
+
+                <data android:scheme="https" />
+                <data
+                    android:host="blog.nuark.xyz"
+                    android:pathPrefix="/blog" />
+            </intent-filter>
+        </activity>
+        <activity
+            android:name=".view.activities.ServiceCommunicatorActivity"
+            android:exported="false" />
+
+        <service
+            android:name=".services.HeavyTask"
+            android:enabled="true"
+            android:exported="true" />
+
+        <activity
+            android:name=".view.activities.ResultActivity"
+            android:exported="false" />
+        <activity
+            android:name=".view.activities.SwitcherActivity"
+            android:exported="false" />
+        <activity
+            android:name=".view.activities.MainActivity"
+            android:exported="true">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+    </application>
+
+</manifest>
--- a/app/src/main/ic_launcher-playstore.png
+++ b/app/src/main/ic_launcher-playstore.png
--- a/app/src/main/java/xyz/nuark/pomslab1/PomsApp.kt
+++ b/app/src/main/java/xyz/nuark/pomslab1/PomsApp.kt
@ -0,0 +1,25 @@
+package xyz.nuark.pomslab1
+
+import android.app.Application
+import androidx.room.Room
+import xyz.nuark.pomslab1.model.repo.AppDatabase
+
+class PomsApp : Application() {
+    lateinit var db: AppDatabase
+        private set
+
+    override fun onCreate() {
+        super.onCreate()
+
+        instance = this
+        db = Room.databaseBuilder(
+            applicationContext,
+            AppDatabase::class.java, "poms-database"
+        ).build()
+    }
+
+    companion object {
+        lateinit var instance: PomsApp
+            private set
+    }
+}
--- a/app/src/main/java/xyz/nuark/pomslab1/model/data/CalculationRecord.kt
+++ b/app/src/main/java/xyz/nuark/pomslab1/model/data/CalculationRecord.kt
@ -0,0 +1,12 @@
+package xyz.nuark.pomslab1.model.data
+
+import androidx.room.ColumnInfo
+import androidx.room.Entity
+import java.util.*
+
+@Entity(tableName = "calc_records", primaryKeys = ["date", "equation"])
+data class CalculationRecord(
+    @ColumnInfo(name = "date") val date: Date,
+    @ColumnInfo(name = "equation") val equation: String,
+    @ColumnInfo(name = "result") val result: String,
+)
--- a/app/src/main/java/xyz/nuark/pomslab1/model/data/QuadraticEquationModel.kt
+++ b/app/src/main/java/xyz/nuark/pomslab1/model/data/QuadraticEquationModel.kt
@ -0,0 +1,61 @@
+package xyz.nuark.pomslab1.model.data
+
+import kotlin.math.sqrt
+
+class QuadraticEquationModel {
+    var a: Double? = null
+    var b: Double? = null
+    var c: Double? = null
+
+    val ok: Boolean get() = a != null && b != null && c != null
+
+    val result: Array<Double>
+        get() {
+            if (!ok) {
+                return emptyArray()
+            }
+            val _a = a!!
+            val _b = b!!
+            val _c = c!!
+            val d = _b * _b - 4 * _a * _c
+            if (d < 0) {
+                return emptyArray()
+            }
+            val x1 = (-_b + sqrt(d)) / (2 * _a)
+            val x2 = (-_b - sqrt(d)) / (2 * _a)
+            return arrayOf(x1, x2)
+        }
+
+    fun setAV(v: String) {
+        a = v.toDoubleOrNull()
+    }
+
+    fun setBV(v: String) {
+        b = v.toDoubleOrNull()
+    }
+
+    fun setCV(v: String) {
+        c = v.toDoubleOrNull()
+    }
+
+    val formatMain: String
+        get() = when (ok) {
+            true -> "$a*x^2 + $b*x + $c"
+            false -> ""
+        }
+
+    val formatResult: String
+        get() = when (result.size) {
+            0 -> "x = []"
+            1 -> "x = ${result[0]}"
+            2 -> "x = [${result[0]}; ${result[1]}]"
+            else -> ""
+        }
+
+    override fun toString(): String {
+        if (!ok) {
+            return ""
+        }
+        return "$formatMain;\n$formatResult"
+    }
+}
--- a/app/src/main/java/xyz/nuark/pomslab1/model/data/SumModel.kt
+++ b/app/src/main/java/xyz/nuark/pomslab1/model/data/SumModel.kt
@ -0,0 +1,45 @@
+package xyz.nuark.pomslab1.model.data
+
+class SumModel {
+    var a: Double? = null
+    var b: Double? = null
+
+    val ok: Boolean get() = a != null && b != null
+
+    val result: Array<Double>
+        get() {
+            if (a == null || b == null) {
+                return emptyArray()
+            }
+            val _a = a!!
+            val _b = b!!
+            return arrayOf(_a + _b)
+        }
+
+    fun setAV(v: String) {
+        a = v.toDoubleOrNull()
+    }
+
+    fun setBV(v: String) {
+        b = v.toDoubleOrNull()
+    }
+
+    val formatMain: String
+        get() = when (ok) {
+            true -> "$a + $b"
+            false -> ""
+        }
+
+    val formatResult: String
+        get() = when (result.size) {
+            1 -> "${result[0]}"
+            else -> ""
+        }
+
+    override fun toString(): String {
+        if (!ok) {
+            return ""
+        }
+        return "$formatMain = $formatResult"
+    }
+}
--- a/app/src/main/java/xyz/nuark/pomslab1/model/interfaces/CalculationRecordDao.kt
+++ b/app/src/main/java/xyz/nuark/pomslab1/model/interfaces/CalculationRecordDao.kt
@ -0,0 +1,20 @@
+package xyz.nuark.pomslab1.model.interfaces
+
+import androidx.lifecycle.LiveData
+import androidx.room.*
+import xyz.nuark.pomslab1.model.data.CalculationRecord
+
+@Dao
+interface CalculationRecordDao {
+    @Query("SELECT * FROM calc_records")
+    fun getAll(): LiveData<List<CalculationRecord>>
+
+    @Insert(onConflict = OnConflictStrategy.REPLACE)
+    fun insertOne(record: CalculationRecord)
+
+    @Insert(onConflict = OnConflictStrategy.REPLACE)
+    fun insertAll(vararg records: CalculationRecord)
+
+    @Delete
+    fun delete(user: CalculationRecord)
+}
--- a/app/src/main/java/xyz/nuark/pomslab1/model/repo/AppDatabase.kt
+++ b/app/src/main/java/xyz/nuark/pomslab1/model/repo/AppDatabase.kt
@ -0,0 +1,14 @@
+package xyz.nuark.pomslab1.model.repo
+
+import androidx.room.Database
+import androidx.room.RoomDatabase
+import androidx.room.TypeConverters
+import xyz.nuark.pomslab1.model.data.CalculationRecord
+import xyz.nuark.pomslab1.model.interfaces.CalculationRecordDao
+import xyz.nuark.pomslab1.utils.RoomConverters
+
+@Database(entities = [CalculationRecord::class], version = 1)
+@TypeConverters(RoomConverters::class)
+abstract class AppDatabase : RoomDatabase() {
+    abstract fun calculationRecordDao(): CalculationRecordDao
+}
--- a/app/src/main/java/xyz/nuark/pomslab1/services/HeavyTask.kt
+++ b/app/src/main/java/xyz/nuark/pomslab1/services/HeavyTask.kt
@ -0,0 +1,88 @@
+package xyz.nuark.pomslab1.services
+
+import android.app.Service
+import android.content.Context
+import android.content.Intent
+import android.os.Binder
+import android.os.IBinder
+import android.util.Log
+import androidx.lifecycle.LiveData
+import androidx.lifecycle.MutableLiveData
+import xyz.nuark.pomslab1.R
+import java.io.*
+
+class HeavyTask : Service() {
+    private val binder = HeavyTaskBinder()
+
+    private val _messengerChannel = MutableLiveData<String>()
+    val messengerChannel: LiveData<String> = _messengerChannel
+
+    private var outputStreamWriter: OutputStreamWriter? = null
+
+    override fun onBind(intent: Intent): IBinder {
+        return binder
+    }
+
+    override fun onUnbind(intent: Intent?): Boolean {
+        return true
+    }
+
+    fun startCalculationOfPI(steps: Int) {
+        outputStreamWriter = OutputStreamWriter(applicationContext.openFileOutput(LOG_FILENAME, Context.MODE_APPEND))
+        log("startCalculationOfPI: starting\n")
+        Thread {
+            _messengerChannel.postValue(buildString {
+                append(getString(R.string.messagePICalculationStarted))
+                append(steps)
+            })
+            var index = 0
+            var pi = 0.0
+            var denominator = 1
+
+            while (index < steps) {
+                if (index % 2 == 0) {
+                    pi += 4.0 / denominator
+                } else {
+                    pi -= 4.0 / denominator
+                }
+
+                index += 1
+                denominator += 2
+            }
+
+            log("startCalculationOfPI: posting value $pi to live data channel\n")
+            _messengerChannel.postValue(getString(R.string.messagePICalculationEnded).format(steps, pi))
+            outputStreamWriter?.flush()
+            outputStreamWriter?.close()
+        }.start()
+    }
+
+    fun getLogText(): String {
+        return try {
+            val inputStream: InputStream = applicationContext.openFileInput(LOG_FILENAME)
+            inputStream.bufferedReader().use(BufferedReader::readText)
+        } catch (e: FileNotFoundException) {
+            Log.e(TAG, "getLogText: ENOENT", e)
+            e.stackTraceToString()
+        } catch (e: IOException) {
+            Log.e(TAG, "getLogText: IOE", e)
+            e.stackTraceToString()
+        }.ifEmpty { getString(R.string.empty) }
+    }
+
+    private fun log(line: String) {
+        outputStreamWriter?.write(line)
+        Log.i(TAG, "log: $outputStreamWriter")
+        Log.i(TAG, line)
+    }
+
+    inner class HeavyTaskBinder : Binder() {
+        val service: HeavyTask get() = this@HeavyTask
+    }
+
+    companion object {
+        const val TAG = "HeavyTask"
+
+        const val LOG_FILENAME = "heavy_task.log"
+    }
+}
--- a/app/src/main/java/xyz/nuark/pomslab1/utils/RoomConverters.kt
+++ b/app/src/main/java/xyz/nuark/pomslab1/utils/RoomConverters.kt
@ -0,0 +1,16 @@
+package xyz.nuark.pomslab1.utils
+
+import androidx.room.TypeConverter
+import java.util.*
+
+class RoomConverters {
+    @TypeConverter
+    fun fromTimestamp(value: Long?): Date? {
+        return if (value == null) null else Date(value)
+    }
+
+    @TypeConverter
+    fun dateToTimestamp(date: Date?): Long? {
+        return date?.time
+    }
+}
--- a/app/src/main/java/xyz/nuark/pomslab1/view/activities/GraphicsActivity.kt
+++ b/app/src/main/java/xyz/nuark/pomslab1/view/activities/GraphicsActivity.kt
@ -0,0 +1,54 @@
+package xyz.nuark.pomslab1.view.activities
+
+import android.os.Bundle
+import androidx.appcompat.app.AppCompatActivity
+import xyz.nuark.pomslab1.databinding.ActivityGraphicsBinding
+
+class GraphicsActivity : AppCompatActivity() {
+    private var _binding: ActivityGraphicsBinding? = null
+    private val binding get() = _binding!!
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        _binding = ActivityGraphicsBinding.inflate(layoutInflater)
+        setContentView(binding.root)
+
+        binding.tractor.setOnClickListener {
+            binding.tractor.apply {
+                clearAnimation()
+                rotation = 0f
+                scaleX = 1f
+                scaleY = 1f
+                translationX = 0f
+                translationY = 0f
+                alpha = 1f
+            }
+        }
+
+        binding.rotate.setOnClickListener {
+            binding.tractor.animate().rotation(3600f).duration = 500
+        }
+
+        binding.scale.setOnClickListener {
+            binding.tractor.animate().scaleXBy(-4f).scaleYBy(-4f).setDuration(1000).withEndAction {
+                binding.tractor.animate().scaleXBy(4f).scaleYBy(4f).duration = 1000
+            }
+
+        }
+
+        binding.translate.setOnClickListener {
+            binding.tractor.animation
+            binding.tractor.animate().translationXBy(-100f).setDuration(100).withEndAction {
+                binding.tractor.animate().translationXBy(200f).setDuration(800).withEndAction {
+                    binding.tractor.animate().translationXBy(-100f).duration = 100
+                }
+            }
+        }
+
+        binding.alpha.setOnClickListener {
+            binding.tractor.animate().alpha(0f).setDuration(100).withEndAction {
+                binding.tractor.animate().alpha(1f).duration = 1000
+            }
+        }
+    }
+}
--- a/app/src/main/java/xyz/nuark/pomslab1/view/activities/LinkerActivity.kt
+++ b/app/src/main/java/xyz/nuark/pomslab1/view/activities/LinkerActivity.kt
@ -0,0 +1,36 @@
+package xyz.nuark.pomslab1.view.activities
+
+import android.content.Intent
+import android.net.Uri
+import android.os.Bundle
+import androidx.appcompat.app.AppCompatActivity
+import androidx.core.text.buildSpannedString
+import xyz.nuark.pomslab1.R
+import xyz.nuark.pomslab1.databinding.ActivityLinkerBinding
+
+class LinkerActivity : AppCompatActivity() {
+    private var _binding: ActivityLinkerBinding? = null
+    private val binding get() = _binding!!
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        _binding = ActivityLinkerBinding.inflate(layoutInflater)
+        setContentView(binding.root)
+
+        binding.intentContents.text = intent.let {
+            buildSpannedString {
+                append(getString(R.string.youTriedToOpen))
+                appendLine(it.dataString)
+            }
+        }
+
+        binding.openInBrowser.setOnClickListener {
+            try {
+                startActivity(Intent.createChooser(Intent(Intent.ACTION_VIEW).apply {
+                    data = Uri.parse(binding.linkEditor.text.toString())
+                }, getString(R.string.chooseBrowserTitle)))
+            } catch (_: Exception) {
+            }
+        }
+    }
+}
--- a/app/src/main/java/xyz/nuark/pomslab1/view/activities/MainActivity.kt
+++ b/app/src/main/java/xyz/nuark/pomslab1/view/activities/MainActivity.kt
@ -0,0 +1,96 @@
+package xyz.nuark.pomslab1.view.activities
+
+import android.content.Context
+import android.content.Intent
+import android.os.Bundle
+import android.util.Log
+import android.view.Menu
+import androidx.appcompat.app.AppCompatActivity
+import androidx.appcompat.app.AppCompatDelegate
+import androidx.core.content.edit
+import xyz.nuark.pomslab1.R
+import xyz.nuark.pomslab1.databinding.ActivityMainBinding
+
+class MainActivity : AppCompatActivity() {
+    private var _binding: ActivityMainBinding? = null
+    private val binding get() = _binding!!
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        updateTheme()
+        super.onCreate(savedInstanceState)
+        _binding = ActivityMainBinding.inflate(layoutInflater)
+        setContentView(binding.root)
+    }
+
+    override fun onCreateOptionsMenu(menu: Menu?): Boolean {
+        return super.onCreateOptionsMenu(menu?.apply {
+            addSubMenu(getString(R.string.openActionsLabel)).apply {
+                add(getString(R.string.openSwitcher))?.apply {
+                    setOnMenuItemClickListener {
+                        startActivity(Intent(this@MainActivity, SwitcherActivity::class.java).apply {
+                            addFlags(Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_CLEAR_TASK)
+                        })
+                        true
+                    }
+                }
+                add(getString(R.string.openCalcHistory))?.apply {
+                    setOnMenuItemClickListener {
+                        startActivity(Intent(this@MainActivity, ResultActivity::class.java))
+                        true
+                    }
+                }
+                add(getString(R.string.openHeavyTaskConnector))?.apply {
+                    setOnMenuItemClickListener {
+                        startActivity(Intent(this@MainActivity, ServiceCommunicatorActivity::class.java))
+                        true
+                    }
+                }
+                add(getString(R.string.openGraphicsActivity))?.apply {
+                    setOnMenuItemClickListener {
+                        startActivity(Intent(this@MainActivity, GraphicsActivity::class.java))
+                        true
+                    }
+                }
+            }
+            val sp = getSharedPreferences(SPG_THEME_MODE, Context.MODE_PRIVATE)
+            if (sp.getBoolean(SP_LIGHT_MODE_ENABLED, false)) {
+                add(getString(R.string.switchToDarkLabel))?.apply {
+                    setOnMenuItemClickListener {
+                        sp.edit(true) {
+                            putBoolean(SP_LIGHT_MODE_ENABLED, false)
+                        }
+                        updateTheme()
+                        true
+                    }
+                }
+            } else {
+                add(getString(R.string.switchToLightLabel))?.apply {
+                    setOnMenuItemClickListener {
+                        sp.edit(true) {
+                            putBoolean(SP_LIGHT_MODE_ENABLED, true)
+                        }
+                        updateTheme()
+                        true
+                    }
+                }
+            }
+        })
+    }
+
+    private fun updateTheme() {
+        val sp = getSharedPreferences(SPG_THEME_MODE, Context.MODE_PRIVATE)
+        val lightMode = when (sp.getBoolean(SP_LIGHT_MODE_ENABLED, false)) {
+            true -> AppCompatDelegate.MODE_NIGHT_NO
+            false -> AppCompatDelegate.MODE_NIGHT_YES
+        }
+        Log.i(TAG, "updateTheme: lightMode")
+        AppCompatDelegate.setDefaultNightMode(lightMode)
+    }
+
+    companion object {
+        const val TAG = "MainActivity"
+
+        const val SPG_THEME_MODE = "SPG_THEME_MODE"
+        const val SP_LIGHT_MODE_ENABLED = "SP_LIGHT_MODE_ENABLED"
+    }
+}
--- a/app/src/main/java/xyz/nuark/pomslab1/view/activities/ResultActivity.kt
+++ b/app/src/main/java/xyz/nuark/pomslab1/view/activities/ResultActivity.kt
@ -0,0 +1,33 @@
+package xyz.nuark.pomslab1.view.activities
+
+import android.os.Bundle
+import android.view.View
+import androidx.activity.viewModels
+import androidx.appcompat.app.AppCompatActivity
+import androidx.recyclerview.widget.LinearLayoutManager
+import xyz.nuark.pomslab1.databinding.ActivityResultBinding
+import xyz.nuark.pomslab1.view.adapters.CalculationHistoryAdapter
+import xyz.nuark.pomslab1.viewmodels.ResultActivityViewModel
+
+class ResultActivity : AppCompatActivity() {
+    private var _binding: ActivityResultBinding? = null
+    private val binding get() = _binding!!
+
+    private val viewModel: ResultActivityViewModel by viewModels()
+
+    private val adapter = CalculationHistoryAdapter()
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        _binding = ActivityResultBinding.inflate(layoutInflater)
+        setContentView(binding.root)
+
+        viewModel.records.observe(this) {
+            binding.noHistoryLabel.visibility = if (it.isEmpty()) View.VISIBLE else View.GONE
+            adapter.setRecords(it)
+        }
+
+        binding.historyList.layoutManager = LinearLayoutManager(this, LinearLayoutManager.VERTICAL, true)
+        binding.historyList.adapter = adapter
+    }
+}
--- a/app/src/main/java/xyz/nuark/pomslab1/view/activities/ServiceCommunicatorActivity.kt
+++ b/app/src/main/java/xyz/nuark/pomslab1/view/activities/ServiceCommunicatorActivity.kt
@ -0,0 +1,146 @@
+package xyz.nuark.pomslab1.view.activities
+
+import android.content.ComponentName
+import android.content.Context
+import android.content.Intent
+import android.content.ServiceConnection
+import android.os.Bundle
+import android.os.IBinder
+import android.util.Log
+import androidx.appcompat.app.AppCompatActivity
+import androidx.lifecycle.LifecycleOwner
+import androidx.lifecycle.LiveData
+import androidx.lifecycle.MutableLiveData
+import xyz.nuark.pomslab1.R
+import xyz.nuark.pomslab1.databinding.ActivityServiceCommunicatorBinding
+import xyz.nuark.pomslab1.services.HeavyTask
+
+class ServiceCommunicatorActivity : AppCompatActivity() {
+    private var _binding: ActivityServiceCommunicatorBinding? = null
+    private val binding get() = _binding!!
+
+    private val connection = HeavyServiceConnector()
+    private lateinit var heavyIntentService: Intent
+
+    private var subscribed = false
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        _binding = ActivityServiceCommunicatorBinding.inflate(layoutInflater)
+        setContentView(binding.root)
+
+        heavyIntentService = Intent(this, HeavyTask::class.java)
+
+        binding.serviceController.setOnClickListener {
+            if (connection.bound.value == true) {
+                unbindService(connection)
+                connection.stopService(this)
+                subscribed = false
+            } else {
+                binding.logHolder.text = ""
+                bindService(heavyIntentService, connection, Context.BIND_AUTO_CREATE)
+            }
+        }
+
+        binding.calc.setOnClickListener {
+            val stepsString = binding.stepsCount.editText?.text?.toString() ?: ""
+            if (stepsString.isEmpty()) {
+                return@setOnClickListener
+            }
+            val steps = stepsString.toIntOrNull()
+            if (steps == null || steps <= 0) {
+                return@setOnClickListener
+            }
+
+            val binder = connection.binder
+            if (connection.bound.value == true && binder != null && binder.isBinderAlive) {
+                Log.i(TAG, "onCreate: service is ready for work!")
+                binder.service.startCalculationOfPI(steps)
+                Log.i(TAG, "onCreate: started calculation thread in service for 200 steps")
+                if (!subscribed) {
+                    binder.service.messengerChannel.observe(this) {
+                        appendLogLine(it)
+                    }
+                    subscribed = true
+                }
+            } else {
+                Log.i(TAG, "onCreate: service is not ready! (binder: $binder)")
+            }
+        }
+
+        binding.readServiceLog.setOnClickListener {
+            connection.binder?.service?.let {
+                binding.serviceLogHolder.text = it.getLogText()
+            }
+        }
+
+        connection.bound.observe(this) { result ->
+            binding.serviceController.apply {
+                setChipIconResource(if (result) R.drawable.baseline_play_arrow_24 else R.drawable.baseline_stop_24)
+                setChipIconTintResource(if (result) R.color.green else R.color.red)
+                text = getText(if (result) R.string.serviceStatusRunning else R.string.serviceStatusStopped)
+            }
+        }
+    }
+
+    private fun appendLogLine(line: String) {
+        binding.logHolder.text = buildString {
+            appendLine(line)
+            append(binding.logHolder.text)
+        }
+    }
+
+    override fun onDestroy() {
+        if (connection.bound.value == true) {
+            unbindService(connection)
+        }
+        super.onDestroy()
+    }
+
+    class HeavyServiceConnector : ServiceConnection {
+        private var _bound = MutableLiveData<Boolean>()
+        val bound: LiveData<Boolean> get() = _bound
+
+        var binder: HeavyTask.HeavyTaskBinder? = null
+            private set
+
+        init {
+            _bound.value = false
+        }
+
+        override fun onServiceConnected(service: ComponentName?, binder: IBinder?) {
+            Log.i(TAG, "onServiceConnected: service connected, got $service and $binder")
+            if (binder == null) {
+                Log.e(TAG, "onServiceConnected: binder is null!")
+                return
+            }
+            if (binder !is HeavyTask.HeavyTaskBinder) {
+                Log.e(TAG, "onServiceConnected: binder is not ours!")
+                return
+            }
+            this.binder = binder
+            _bound.value = true
+        }
+
+        override fun onServiceDisconnected(service: ComponentName?) {
+            Log.i(TAG, "onServiceDisconnected: service disconnected, got $service")
+            binder = null
+            _bound.value = false
+        }
+
+        fun stopService(lifecycleOwner: LifecycleOwner) {
+            binder?.service?.stopSelf()
+            binder?.service?.messengerChannel?.removeObservers(lifecycleOwner)
+            binder = null
+            _bound.value = false
+        }
+
+        companion object {
+            const val TAG = "HeavyServiceConnector"
+        }
+    }
+
+    companion object {
+        const val TAG = "ServiceCommunicatorActivity"
+    }
+}
--- a/app/src/main/java/xyz/nuark/pomslab1/view/activities/SwitcherActivity.kt
+++ b/app/src/main/java/xyz/nuark/pomslab1/view/activities/SwitcherActivity.kt
@ -0,0 +1,78 @@
+package xyz.nuark.pomslab1.view.activities
+
+import android.content.Intent
+import android.os.Bundle
+import android.view.Menu
+import androidx.appcompat.app.AppCompatActivity
+import xyz.nuark.pomslab1.R
+import xyz.nuark.pomslab1.databinding.ActivitySwitcherBinding
+import xyz.nuark.pomslab1.view.fragments.QuadraticFragment
+import xyz.nuark.pomslab1.view.fragments.SumFragment
+
+class SwitcherActivity : AppCompatActivity() {
+    private var _binding: ActivitySwitcherBinding? = null
+    private val binding get() = _binding!!
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        _binding = ActivitySwitcherBinding.inflate(layoutInflater)
+        setContentView(binding.root)
+
+        supportFragmentManager
+            .beginTransaction().apply {
+                add(binding.fragmentHolder.id, sumFragment)
+                add(binding.fragmentHolder.id, quadraticFragment)
+            }
+            .commit()
+        supportFragmentManager.executePendingTransactions()
+        supportFragmentManager
+            .beginTransaction().apply {
+                detach(sumFragment)
+            }
+            .commit()
+    }
+
+    override fun onCreateOptionsMenu(menu: Menu?): Boolean {
+        return super.onCreateOptionsMenu(menu?.apply {
+            add(getString(R.string.openMultipanel))?.apply {
+                setOnMenuItemClickListener {
+                    startActivity(Intent(this@SwitcherActivity, MainActivity::class.java).apply {
+                        addFlags(Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_CLEAR_TASK)
+                    })
+                    true
+                }
+            }
+            add(getString(R.string.switchFragment))?.apply {
+                setOnMenuItemClickListener {
+                    this@SwitcherActivity.switchFragment()
+                    true
+                }
+            }
+            add(getString(R.string.openCalcHistory))?.apply {
+                setOnMenuItemClickListener {
+                    startActivity(Intent(this@SwitcherActivity, ResultActivity::class.java))
+                    true
+                }
+            }
+        })
+    }
+
+    private fun switchFragment() {
+        supportFragmentManager
+            .beginTransaction().apply {
+                if (quadraticFragment.isDetached) {
+                    detach(sumFragment)
+                    attach(quadraticFragment)
+                } else if (sumFragment.isDetached) {
+                    attach(sumFragment)
+                    detach(quadraticFragment)
+                }
+            }
+            .commit()
+    }
+
+    companion object {
+        private val quadraticFragment = QuadraticFragment()
+        private val sumFragment = SumFragment()
+    }
+}
--- a/app/src/main/java/xyz/nuark/pomslab1/view/adapters/CalculationHistoryAdapter.kt
+++ b/app/src/main/java/xyz/nuark/pomslab1/view/adapters/CalculationHistoryAdapter.kt
@ -0,0 +1,58 @@
+package xyz.nuark.pomslab1.view.adapters
+
+import android.view.LayoutInflater
+import android.view.ViewGroup
+import androidx.recyclerview.widget.RecyclerView
+import xyz.nuark.pomslab1.databinding.CalculationHistoryItemBinding
+import xyz.nuark.pomslab1.model.data.CalculationRecord
+import java.text.SimpleDateFormat
+import java.util.*
+
+class CalculationHistoryAdapter : RecyclerView.Adapter<CalculationHistoryAdapter.VH>() {
+    private val records = arrayListOf<CalculationRecord>()
+
+    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): VH {
+        val inflater = LayoutInflater.from(parent.context)
+        val binding = CalculationHistoryItemBinding.inflate(
+            inflater, parent,
+            false
+        )
+        return VH(binding)
+    }
+
+    override fun getItemCount(): Int {
+        return records.size
+    }
+
+    override fun onBindViewHolder(holder: VH, position: Int) {
+        holder.bind(records[position])
+    }
+
+    fun setRecords(newRecords: List<CalculationRecord>) {
+        val size = records.size
+        records.clear()
+        if (size > 0) {
+            notifyItemRangeRemoved(0, size)
+        }
+        records.addAll(newRecords)
+        if (records.size > 0) {
+            notifyItemRangeInserted(0, records.size)
+        }
+    }
+
+    fun isEmpty(): Boolean {
+        return records.isEmpty()
+    }
+
+    class VH(private val binding: CalculationHistoryItemBinding) : RecyclerView.ViewHolder(binding.root) {
+        fun bind(record: CalculationRecord) {
+            binding.dateHolder.text = formatter.format(record.date)
+            binding.equHolder.text = record.equation
+            binding.resultHolder.text = record.result
+        }
+    }
+
+    companion object {
+        private val formatter = SimpleDateFormat("dd.MM.yy HH:mm:ss", Locale.CANADA)
+    }
+}
--- a/app/src/main/java/xyz/nuark/pomslab1/view/fragments/QuadraticFragment.kt
+++ b/app/src/main/java/xyz/nuark/pomslab1/view/fragments/QuadraticFragment.kt
@ -0,0 +1,36 @@
+package xyz.nuark.pomslab1.view.fragments
+
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import androidx.fragment.app.Fragment
+import androidx.fragment.app.activityViewModels
+import xyz.nuark.pomslab1.databinding.FragmentQuadraticBinding
+import xyz.nuark.pomslab1.viewmodels.QuadraticCalculationViewModel
+
+class QuadraticFragment : Fragment() {
+    private var _binding: FragmentQuadraticBinding? = null
+    private val binding get() = _binding!!
+
+    private val calculationViewModel: QuadraticCalculationViewModel by activityViewModels()
+
+    override fun onCreateView(
+        inflater: LayoutInflater, container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View {
+        _binding = FragmentQuadraticBinding.inflate(inflater)
+        binding.equation = calculationViewModel.quadraticEquationModel
+        binding.resultString = calculationViewModel.quadraticEquationModel.toString()
+        return binding.root
+    }
+
+    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
+        super.onViewCreated(view, savedInstanceState)
+
+        binding.button.setOnClickListener { v: View? ->
+            binding.resultString = calculationViewModel.quadraticEquationModel.toString()
+            calculationViewModel.saveQuadraticCalculation()
+        }
+    }
+}
--- a/app/src/main/java/xyz/nuark/pomslab1/view/fragments/SumFragment.kt
+++ b/app/src/main/java/xyz/nuark/pomslab1/view/fragments/SumFragment.kt
@ -0,0 +1,36 @@
+package xyz.nuark.pomslab1.view.fragments
+
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import androidx.fragment.app.Fragment
+import androidx.fragment.app.activityViewModels
+import xyz.nuark.pomslab1.databinding.FragmentSumBinding
+import xyz.nuark.pomslab1.viewmodels.SumCalculationViewModel
+
+class SumFragment : Fragment() {
+    private var _binding: FragmentSumBinding? = null
+    private val binding get() = _binding!!
+
+    private val calculationViewModel: SumCalculationViewModel by activityViewModels()
+
+    override fun onCreateView(
+        inflater: LayoutInflater, container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View {
+        _binding = FragmentSumBinding.inflate(inflater)
+        binding.equation = calculationViewModel.sumModel
+        binding.resultString = calculationViewModel.sumModel.toString()
+        return binding.root
+    }
+
+    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
+        super.onViewCreated(view, savedInstanceState)
+
+        binding.button.setOnClickListener { v: View? ->
+            binding.resultString = calculationViewModel.sumModel.toString()
+            calculationViewModel.saveSumCalculation()
+        }
+    }
+}
--- a/app/src/main/java/xyz/nuark/pomslab1/viewmodels/QuadraticCalculationViewModel.kt
+++ b/app/src/main/java/xyz/nuark/pomslab1/viewmodels/QuadraticCalculationViewModel.kt
@ -0,0 +1,23 @@
+package xyz.nuark.pomslab1.viewmodels
+
+import androidx.lifecycle.ViewModel
+import xyz.nuark.pomslab1.PomsApp
+import xyz.nuark.pomslab1.model.data.CalculationRecord
+import xyz.nuark.pomslab1.model.data.QuadraticEquationModel
+import java.util.*
+
+class QuadraticCalculationViewModel : ViewModel() {
+    val quadraticEquationModel = QuadraticEquationModel()
+
+    fun saveQuadraticCalculation() {
+        if (quadraticEquationModel.ok) {
+            Thread {
+                PomsApp.instance.db.calculationRecordDao().insertOne(
+                    CalculationRecord(
+                        Date(), quadraticEquationModel.formatMain, quadraticEquationModel.formatResult
+                    )
+                )
+            }.start()
+        }
+    }
+}
--- a/app/src/main/java/xyz/nuark/pomslab1/viewmodels/ResultActivityViewModel.kt
+++ b/app/src/main/java/xyz/nuark/pomslab1/viewmodels/ResultActivityViewModel.kt
@ -0,0 +1,10 @@
+package xyz.nuark.pomslab1.viewmodels
+
+import androidx.lifecycle.LiveData
+import androidx.lifecycle.ViewModel
+import xyz.nuark.pomslab1.PomsApp
+import xyz.nuark.pomslab1.model.data.CalculationRecord
+
+class ResultActivityViewModel : ViewModel() {
+    val records: LiveData<List<CalculationRecord>> = PomsApp.instance.db.calculationRecordDao().getAll()
+}
--- a/app/src/main/java/xyz/nuark/pomslab1/viewmodels/SumCalculationViewModel.kt
+++ b/app/src/main/java/xyz/nuark/pomslab1/viewmodels/SumCalculationViewModel.kt
@ -0,0 +1,23 @@
+package xyz.nuark.pomslab1.viewmodels
+
+import androidx.lifecycle.ViewModel
+import xyz.nuark.pomslab1.PomsApp
+import xyz.nuark.pomslab1.model.data.CalculationRecord
+import xyz.nuark.pomslab1.model.data.SumModel
+import java.util.*
+
+class SumCalculationViewModel : ViewModel() {
+    val sumModel = SumModel()
+
+    fun saveSumCalculation() {
+        if (sumModel.ok) {
+            Thread {
+                PomsApp.instance.db.calculationRecordDao().insertOne(
+                    CalculationRecord(
+                        Date(), sumModel.formatMain, sumModel.formatResult
+                    )
+                )
+            }.start()
+        }
+    }
+}
--- a/app/src/main/res/drawable/baseline_play_arrow_24.xml
+++ b/app/src/main/res/drawable/baseline_play_arrow_24.xml
@ -0,0 +1,5 @@
+<vector android:height="24dp" android:tint="#000000"
+    android:viewportHeight="24" android:viewportWidth="24"
+    android:width="24dp" xmlns:android="http://schemas.android.com/apk/res/android">
+    <path android:fillColor="@android:color/white" android:pathData="M8,5v14l11,-7z"/>
+</vector>
--- a/app/src/main/res/drawable/baseline_stop_24.xml
+++ b/app/src/main/res/drawable/baseline_stop_24.xml
@ -0,0 +1,5 @@
+<vector android:height="24dp" android:tint="#000000"
+    android:viewportHeight="24" android:viewportWidth="24"
+    android:width="24dp" xmlns:android="http://schemas.android.com/apk/res/android">
+    <path android:fillColor="@android:color/white" android:pathData="M6,6h12v12H6z"/>
+</vector>
--- a/app/src/main/res/drawable/ic_launcher_background.xml
+++ b/app/src/main/res/drawable/ic_launcher_background.xml
@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportWidth="108"
+    android:viewportHeight="108">
+    <path
+        android:fillColor="#FFFA01"
+        android:pathData="M0,0h108v108h-108z" />
+</vector>
--- a/app/src/main/res/drawable/ic_launcher_foreground.xml
+++ b/app/src/main/res/drawable/ic_launcher_foreground.xml
@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="utf-8"?>
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportWidth="367"
+    android:viewportHeight="210.30469">
+  <group android:scaleX="0.47314286"
+      android:scaleY="0.2711285"
+      android:translateX="95.87438"
+      android:translateY="83.09189">
+    <group android:translateY="129.44531">
+      <path android:pathData="M41,-33.140625L41,-58.265625Q50,-58.265625,50,-64.390625Q50,-70,43.53125,-70Q37,-70,37,-62.625L37,-0L8,-0L8,-59.671875Q8,-68.890625,9.859375,-74.78125Q11.71875,-80.6875,16.21875,-85.78125Q21.265625,-91.4375,28.84375,-94.71875Q36.4375,-98,44.515625,-98Q59.125,-98,69.0625,-88.1875Q79,-78.390625,79,-63.890625Q79,-49.8125,70.046875,-41.0625Q61.875,-33,45.375,-33L41,-33.140625Z"
+          android:fillColor="#020903"/>
+      <path android:pathData="M136.34375,-98Q156.76562,-98,171.375,-83.265625Q186,-68.546875,186,-48.03125Q186,-27.171875,171.28125,-12.578125Q156.5625,2,135.5,2Q114.578125,2,99.78125,-12.65625Q85,-27.3125,85,-48.03125Q85,-68.96875,99.890625,-83.484375Q114.796875,-98,136.34375,-98ZM135.5,-70Q126.578125,-70,120.28125,-63.546875Q114,-57.109375,114,-48Q114,-38.890625,120.3125,-32.4375Q126.640625,-26,135.5,-26Q144.5,-26,150.75,-32.40625Q157,-38.828125,157,-48Q157,-57.171875,150.75,-63.578125Q144.5,-70,135.5,-70Z"
+          android:fillColor="#020903"/>
+      <path android:pathData="M198,0L198,-69.078125Q198,-81.828125,205.75,-89.90625Q213.5,-98,225.85938,-98Q240.53125,-98,248.42188,-84.765625Q253.25,-91.890625,258.76562,-94.9375Q264.29688,-98,272.42188,-98Q285.28125,-98,292.14062,-89.90625Q299,-81.828125,299,-66.625L299,0L270,0L270,-62.34375Q270,-66.984375,269.34375,-68.484375Q268.70312,-70,266.71875,-70Q263,-70,263,-62.84375L263,0L234,0L234,-62.34375Q234,-66.90625,233.32812,-68.453125Q232.65625,-70,230.6875,-70Q227,-70,227,-62.34375L227,0L198,0Z"
+          android:fillColor="#020903"/>
+      <path android:pathData="M362,-96.421875L362,-68.9375Q359.0625,-70,357.46875,-70Q354.40625,-70,352.20312,-67.625Q350,-65.25,350,-61.90625Q350,-59.03125,352.39062,-54.640625L354.4375,-50.859375Q360,-40.671875,360,-31.171875Q360,-17.28125,350.01562,-7.640625Q340.04688,2,325.67188,2Q318.76562,2,312,-0.78125L312,-28.5Q316.09375,-26,319.26562,-26Q323,-26,325.5,-28.125Q328,-30.265625,328,-33.484375Q328,-35.578125,324.15625,-42.640625Q318,-53.828125,318,-65Q318,-78.5,327.57812,-88.25Q337.17188,-98,350.5,-98Q356.35938,-98,362,-96.421875Z"
+          android:fillColor="#020903"/>
+    </group>
+  </group>
+</vector>
--- a/app/src/main/res/layout-land/activity_main.xml
+++ b/app/src/main/res/layout-land/activity_main.xml
@ -0,0 +1,49 @@
+<?xml version="1.0" encoding="utf-8"?>
+<HorizontalScrollView xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="horizontal"
+    tools:context=".view.activities.MainActivity">
+
+    <LinearLayout
+        android:layout_width="wrap_content"
+        android:layout_height="match_parent"
+        android:orientation="horizontal">
+
+        <androidx.cardview.widget.CardView
+            android:layout_width="400dp"
+            android:layout_height="match_parent"
+            android:layout_margin="8dp"
+            android:elevation="16dp"
+            android:padding="8dp"
+            app:contentPadding="8dp">
+
+            <androidx.fragment.app.FragmentContainerView
+                android:id="@+id/quadraticHolder"
+                android:name="xyz.nuark.pomslab1.view.fragments.QuadraticFragment"
+                android:layout_width="match_parent"
+                android:layout_height="match_parent"
+                tools:layout="@layout/fragment_quadratic" />
+
+        </androidx.cardview.widget.CardView>
+
+        <androidx.cardview.widget.CardView
+            android:layout_width="400dp"
+            android:layout_height="match_parent"
+            android:layout_margin="8dp"
+            android:elevation="16dp"
+            android:padding="8dp">
+
+            <androidx.fragment.app.FragmentContainerView
+                android:id="@+id/sumHolder"
+                android:name="xyz.nuark.pomslab1.view.fragments.SumFragment"
+                android:layout_width="match_parent"
+                android:layout_height="match_parent"
+                tools:layout="@layout/fragment_sum" />
+
+        </androidx.cardview.widget.CardView>
+    </LinearLayout>
+
+</HorizontalScrollView>
--- a/app/src/main/res/layout-land/fragment_quadratic.xml
+++ b/app/src/main/res/layout-land/fragment_quadratic.xml
@ -0,0 +1,112 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layout>
+
+    <data>
+
+        <variable
+            name="equation"
+            type="xyz.nuark.pomslab1.model.data.QuadraticEquationModel" />
+
+        <variable
+            name="resultString"
+            type="String" />
+    </data>
+
+    <androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+        xmlns:app="http://schemas.android.com/apk/res-auto"
+        xmlns:tools="http://schemas.android.com/tools"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        tools:context=".view.fragments.QuadraticFragment">
+
+        <TextView
+            android:id="@+id/textView"
+            style="@style/TextAppearance.AppCompat.Headline"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:text="@string/title"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toTopOf="parent" />
+
+        <EditText
+            android:id="@+id/aCoef"
+            android:layout_width="0dp"
+            android:layout_height="64dp"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:ems="10"
+            android:hint="@string/a"
+            android:inputType="numberDecimal|numberSigned"
+            android:onTextChanged="@{(cs, s, b, c) -> equation.setAV(cs.toString())}"
+            android:text="@{``+(equation.a ?? ``)}"
+            app:layout_constraintEnd_toStartOf="@+id/bCoef"
+            app:layout_constraintHorizontal_bias="0.5"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/textView" />
+
+        <EditText
+            android:id="@+id/bCoef"
+            android:layout_width="0dp"
+            android:layout_height="64dp"
+            android:layout_marginStart="16dp"
+            android:ems="10"
+            android:hint="@string/b"
+            android:inputType="numberDecimal|numberSigned"
+            android:onTextChanged="@{(cs, s, b, c) -> equation.setBV(cs.toString())}"
+            android:text="@{``+(equation.b ?? ``)}"
+            app:layout_constraintEnd_toStartOf="@+id/cCoef"
+            app:layout_constraintHorizontal_bias="0.5"
+            app:layout_constraintStart_toEndOf="@+id/aCoef"
+            app:layout_constraintTop_toTopOf="@+id/aCoef" />
+
+        <EditText
+            android:id="@+id/cCoef"
+            android:layout_width="0dp"
+            android:layout_height="64dp"
+            android:layout_marginStart="16dp"
+            android:layout_marginEnd="16dp"
+            android:ems="10"
+            android:hint="@string/c"
+            android:inputType="numberDecimal|numberSigned"
+            android:onTextChanged="@{(cs, s, b, c) -> equation.setCV(cs.toString())}"
+            android:text="@{``+(equation.c ?? ``)}"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintHorizontal_bias="0.5"
+            app:layout_constraintStart_toEndOf="@+id/bCoef"
+            app:layout_constraintTop_toTopOf="@+id/bCoef" />
+
+        <Button
+            android:id="@+id/button"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:text="@string/calculate"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/cCoef" />
+
+        <TextView
+            android:id="@+id/result"
+            style="@style/TextAppearance.AppCompat.Headline"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:layout_marginBottom="16dp"
+            android:text="@{resultString}"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintHorizontal_bias="0.0"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/button"
+            app:layout_constraintVertical_bias="0.0" />
+
+    </androidx.constraintlayout.widget.ConstraintLayout>
+</layout>
--- a/app/src/main/res/layout-land/fragment_sum.xml
+++ b/app/src/main/res/layout-land/fragment_sum.xml
@ -0,0 +1,99 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layout>
+
+    <data>
+
+        <variable
+            name="equation"
+            type="xyz.nuark.pomslab1.model.data.SumModel" />
+
+        <variable
+            name="resultString"
+            type="String" />
+    </data>
+
+    <androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+        xmlns:app="http://schemas.android.com/apk/res-auto"
+        xmlns:tools="http://schemas.android.com/tools"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        tools:context=".view.fragments.SumFragment">
+
+        <TextView
+            android:id="@+id/textView"
+            style="@style/TextAppearance.AppCompat.Headline"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:text="@string/sumTitle"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toTopOf="parent" />
+
+        <EditText
+            android:id="@+id/aCoef"
+            android:layout_width="0dp"
+            android:layout_height="64dp"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="8dp"
+            android:ems="10"
+            android:hint="@string/a"
+            android:inputType="numberDecimal|numberSigned"
+            android:onTextChanged="@{(cs, s, b, c) -> equation.setAV(cs.toString())}"
+            android:text="@{``+(equation.a ?? ``)}"
+            app:layout_constraintEnd_toStartOf="@+id/bCoef"
+            app:layout_constraintHorizontal_bias="0.5"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/textView" />
+
+        <EditText
+            android:id="@+id/bCoef"
+            android:layout_width="0dp"
+            android:layout_height="64dp"
+            android:layout_marginStart="8dp"
+            android:layout_marginEnd="16dp"
+            android:ems="10"
+            android:hint="@string/b"
+            android:inputType="numberDecimal|numberSigned"
+            android:onTextChanged="@{(cs, s, b, c) -> equation.setBV(cs.toString())}"
+            android:text="@{``+(equation.b ?? ``)}"
+            app:layout_constraintBottom_toBottomOf="@+id/aCoef"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintHorizontal_bias="0.5"
+            app:layout_constraintStart_toEndOf="@+id/aCoef"
+            app:layout_constraintTop_toTopOf="@+id/aCoef" />
+
+        <Button
+            android:id="@+id/button"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:text="@string/calculate"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/bCoef" />
+
+        <TextView
+            android:id="@+id/result"
+            style="@style/TextAppearance.AppCompat.Headline"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:layout_marginBottom="16dp"
+            android:text="@{resultString}"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintHorizontal_bias="0.0"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/button"
+            app:layout_constraintVertical_bias="0.0" />
+
+    </androidx.constraintlayout.widget.ConstraintLayout>
+</layout>
--- a/app/src/main/res/layout-sw600dp/activity_main.xml
+++ b/app/src/main/res/layout-sw600dp/activity_main.xml
@ -0,0 +1,60 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".view.activities.MainActivity">
+
+    <androidx.cardview.widget.CardView
+        android:id="@+id/cardView"
+        android:layout_width="match_parent"
+        android:layout_height="0dp"
+        android:layout_margin="8dp"
+        android:layout_marginStart="8dp"
+        android:layout_marginTop="8dp"
+        android:layout_marginEnd="8dp"
+        android:elevation="16dp"
+        android:padding="8dp"
+        app:contentPadding="8dp"
+        app:layout_constraintBottom_toTopOf="@+id/cardView2"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintHorizontal_bias="0.5"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent">
+
+        <androidx.fragment.app.FragmentContainerView
+            android:id="@+id/quadraticHolder"
+            android:name="xyz.nuark.pomslab1.view.fragments.QuadraticFragment"
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"
+            tools:layout="@layout/fragment_quadratic" />
+
+    </androidx.cardview.widget.CardView>
+
+    <androidx.cardview.widget.CardView
+        android:id="@+id/cardView2"
+        android:layout_width="match_parent"
+        android:layout_height="0dp"
+        android:layout_margin="8dp"
+        android:layout_marginStart="8dp"
+        android:layout_marginEnd="8dp"
+        android:layout_marginBottom="8dp"
+        android:elevation="16dp"
+        android:padding="8dp"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintHorizontal_bias="0.5"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/cardView">
+
+        <androidx.fragment.app.FragmentContainerView
+            android:id="@+id/sumHolder"
+            android:name="xyz.nuark.pomslab1.view.fragments.SumFragment"
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"
+            tools:layout="@layout/fragment_sum" />
+
+    </androidx.cardview.widget.CardView>
+
+</androidx.constraintlayout.widget.ConstraintLayout>
--- a/app/src/main/res/layout-sw600dp/fragment_quadratic.xml
+++ b/app/src/main/res/layout-sw600dp/fragment_quadratic.xml
@ -0,0 +1,111 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layout>
+
+    <data>
+
+        <variable
+            name="equation"
+            type="xyz.nuark.pomslab1.model.data.QuadraticEquationModel" />
+
+        <variable
+            name="resultString"
+            type="String" />
+    </data>
+
+    <androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+        xmlns:app="http://schemas.android.com/apk/res-auto"
+        xmlns:tools="http://schemas.android.com/tools"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        tools:context=".view.fragments.QuadraticFragment">
+
+        <TextView
+            android:id="@+id/textView"
+            style="@style/TextAppearance.AppCompat.Headline"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:text="@string/title"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toTopOf="parent" />
+
+        <EditText
+            android:id="@+id/aCoef"
+            android:layout_width="0dp"
+            android:layout_height="64dp"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:ems="10"
+            android:hint="@string/a"
+            android:inputType="numberDecimal|numberSigned"
+            android:onTextChanged="@{(cs, s, b, c) -> equation.setAV(cs.toString())}"
+            android:text="@{``+(equation.a ?? ``)}"
+            app:layout_constraintEnd_toStartOf="@+id/bCoef"
+            app:layout_constraintHorizontal_bias="0.5"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/textView" />
+
+        <EditText
+            android:id="@+id/bCoef"
+            android:layout_width="0dp"
+            android:layout_height="64dp"
+            android:layout_marginStart="16dp"
+            android:ems="10"
+            android:hint="@string/b"
+            android:inputType="numberDecimal|numberSigned"
+            android:onTextChanged="@{(cs, s, b, c) -> equation.setBV(cs.toString())}"
+            android:text="@{``+(equation.b ?? ``)}"
+            app:layout_constraintEnd_toStartOf="@+id/cCoef"
+            app:layout_constraintHorizontal_bias="0.5"
+            app:layout_constraintStart_toEndOf="@+id/aCoef"
+            app:layout_constraintTop_toTopOf="@+id/aCoef" />
+
+        <EditText
+            android:id="@+id/cCoef"
+            android:layout_width="0dp"
+            android:layout_height="64dp"
+            android:layout_marginStart="16dp"
+            android:layout_marginEnd="16dp"
+            android:ems="10"
+            android:hint="@string/c"
+            android:inputType="numberDecimal|numberSigned"
+            android:onTextChanged="@{(cs, s, b, c) -> equation.setCV(cs.toString())}"
+            android:text="@{``+(equation.c ?? ``)}"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintHorizontal_bias="0.5"
+            app:layout_constraintStart_toEndOf="@+id/bCoef"
+            app:layout_constraintTop_toTopOf="@+id/bCoef" />
+
+        <Button
+            android:id="@+id/button"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:layout_marginBottom="16dp"
+            android:text="@string/calculate"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="@+id/cCoef"
+            app:layout_constraintTop_toBottomOf="@+id/cCoef"
+            app:layout_constraintVertical_bias="0.0" />
+
+        <TextView
+            android:id="@+id/result"
+            style="@style/TextAppearance.AppCompat.Headline"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:layout_marginEnd="16dp"
+            android:text="@{resultString}"
+            app:layout_constraintBottom_toBottomOf="@+id/button"
+            app:layout_constraintEnd_toStartOf="@+id/button"
+            app:layout_constraintHorizontal_bias="0.0"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toTopOf="@+id/button" />
+
+    </androidx.constraintlayout.widget.ConstraintLayout>
+</layout>
--- a/app/src/main/res/layout-sw600dp/fragment_sum.xml
+++ b/app/src/main/res/layout-sw600dp/fragment_sum.xml
@ -0,0 +1,98 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layout>
+
+    <data>
+
+        <variable
+            name="equation"
+            type="xyz.nuark.pomslab1.model.data.SumModel" />
+
+        <variable
+            name="resultString"
+            type="String" />
+    </data>
+
+    <androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+        xmlns:app="http://schemas.android.com/apk/res-auto"
+        xmlns:tools="http://schemas.android.com/tools"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        tools:context=".view.fragments.SumFragment">
+
+        <TextView
+            android:id="@+id/textView"
+            style="@style/TextAppearance.AppCompat.Headline"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:text="@string/sumTitle"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toTopOf="parent" />
+
+        <EditText
+            android:id="@+id/aCoef"
+            android:layout_width="0dp"
+            android:layout_height="64dp"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="8dp"
+            android:ems="10"
+            android:hint="@string/a"
+            android:inputType="numberDecimal|numberSigned"
+            android:onTextChanged="@{(cs, s, b, c) -> equation.setAV(cs.toString())}"
+            android:text="@{``+(equation.a ?? ``)}"
+            app:layout_constraintEnd_toStartOf="@+id/bCoef"
+            app:layout_constraintHorizontal_bias="0.5"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/textView" />
+
+        <EditText
+            android:id="@+id/bCoef"
+            android:layout_width="0dp"
+            android:layout_height="64dp"
+            android:layout_marginStart="8dp"
+            android:layout_marginEnd="16dp"
+            android:ems="10"
+            android:hint="@string/b"
+            android:inputType="numberDecimal|numberSigned"
+            android:onTextChanged="@{(cs, s, b, c) -> equation.setBV(cs.toString())}"
+            android:text="@{``+(equation.b ?? ``)}"
+            app:layout_constraintBottom_toBottomOf="@+id/aCoef"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintHorizontal_bias="0.5"
+            app:layout_constraintStart_toEndOf="@+id/aCoef"
+            app:layout_constraintTop_toTopOf="@+id/aCoef" />
+
+        <Button
+            android:id="@+id/button"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:layout_marginBottom="16dp"
+            android:text="@string/calculate"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="@+id/bCoef"
+            app:layout_constraintTop_toBottomOf="@+id/bCoef"
+            app:layout_constraintVertical_bias="0.0" />
+
+        <TextView
+            android:id="@+id/result"
+            style="@style/TextAppearance.AppCompat.Headline"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:layout_marginEnd="16dp"
+            android:text="@{resultString}"
+            app:layout_constraintBottom_toBottomOf="@+id/button"
+            app:layout_constraintEnd_toStartOf="@+id/button"
+            app:layout_constraintHorizontal_bias="0.0"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toTopOf="@+id/button" />
+
+    </androidx.constraintlayout.widget.ConstraintLayout>
+</layout>
--- a/app/src/main/res/layout/activity_graphics.xml
+++ b/app/src/main/res/layout/activity_graphics.xml
@ -0,0 +1,79 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".view.activities.GraphicsActivity">
+
+    <ImageView
+        android:id="@+id/tractor"
+        android:layout_width="300dp"
+        android:layout_height="300dp"
+        android:scaleType="centerCrop"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent"
+        app:srcCompat="@raw/shining_tractor" />
+
+    <Button
+        android:id="@+id/rotate"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="8dp"
+        android:layout_marginEnd="2dp"
+        android:layout_marginBottom="8dp"
+        android:layout_weight="1"
+        android:text="@string/rotate"
+        android:textSize="12sp"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintEnd_toStartOf="@+id/scale"
+        app:layout_constraintHorizontal_bias="0.5"
+        app:layout_constraintStart_toStartOf="parent" />
+
+    <Button
+        android:id="@+id/scale"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="2dp"
+        android:layout_marginEnd="2dp"
+        android:layout_marginBottom="8dp"
+        android:layout_weight="1"
+        android:text="@string/scale"
+        android:textSize="12sp"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintEnd_toStartOf="@+id/translate"
+        app:layout_constraintHorizontal_bias="0.5"
+        app:layout_constraintStart_toEndOf="@+id/rotate" />
+
+    <Button
+        android:id="@+id/translate"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="2dp"
+        android:layout_marginEnd="2dp"
+        android:layout_marginBottom="8dp"
+        android:layout_weight="1"
+        android:text="@string/translate"
+        android:textSize="12sp"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintEnd_toStartOf="@+id/alpha"
+        app:layout_constraintHorizontal_bias="0.5"
+        app:layout_constraintStart_toEndOf="@+id/scale" />
+
+    <Button
+        android:id="@+id/alpha"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="2dp"
+        android:layout_marginEnd="8dp"
+        android:layout_marginBottom="8dp"
+        android:layout_weight="1"
+        android:text="@string/alpha"
+        android:textSize="12sp"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintHorizontal_bias="0.5"
+        app:layout_constraintStart_toEndOf="@+id/translate" />
+</androidx.constraintlayout.widget.ConstraintLayout>
--- a/app/src/main/res/layout/activity_linker.xml
+++ b/app/src/main/res/layout/activity_linker.xml
@ -0,0 +1,61 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".view.activities.LinkerActivity">
+
+    <Button
+        android:id="@+id/openInBrowser"
+        android:layout_width="0dp"
+        android:layout_height="40dp"
+        android:layout_marginStart="16dp"
+        android:layout_marginTop="8dp"
+        android:layout_marginEnd="16dp"
+        android:text="@string/openInBrowserLabel"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintHorizontal_bias="0.0"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/linkEditor" />
+
+    <TextView
+        android:id="@+id/textView4"
+        android:layout_width="0dp"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="16dp"
+        android:layout_marginTop="16dp"
+        android:layout_marginEnd="16dp"
+        android:text="@string/intentContentsLabel"
+        android:textSize="20sp"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent" />
+
+    <TextView
+        android:id="@+id/intentContents"
+        android:layout_width="0dp"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="16dp"
+        android:layout_marginTop="8dp"
+        android:layout_marginEnd="16dp"
+        android:textSize="16sp"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/textView4"
+        tools:text="TextView" />
+
+    <EditText
+        android:id="@+id/linkEditor"
+        android:layout_width="0dp"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="16dp"
+        android:layout_marginTop="8dp"
+        android:layout_marginEnd="16dp"
+        android:ems="10"
+        android:hint="Link"
+        android:inputType="textUri"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/intentContents" />
+</androidx.constraintlayout.widget.ConstraintLayout>
--- a/app/src/main/res/layout/activity_main.xml
+++ b/app/src/main/res/layout/activity_main.xml
@ -0,0 +1,49 @@
+<?xml version="1.0" encoding="utf-8"?>
+<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical"
+    tools:context=".view.activities.MainActivity">
+
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:orientation="vertical">
+
+        <androidx.cardview.widget.CardView
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_margin="8dp"
+            android:elevation="16dp"
+            android:padding="8dp"
+            app:contentPadding="8dp">
+
+            <androidx.fragment.app.FragmentContainerView
+                android:id="@+id/quadraticHolder"
+                android:name="xyz.nuark.pomslab1.view.fragments.QuadraticFragment"
+                android:layout_width="match_parent"
+                android:layout_height="match_parent"
+                tools:layout="@layout/fragment_quadratic" />
+
+        </androidx.cardview.widget.CardView>
+
+        <androidx.cardview.widget.CardView
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_margin="8dp"
+            android:elevation="16dp"
+            android:padding="8dp">
+
+            <androidx.fragment.app.FragmentContainerView
+                android:id="@+id/sumHolder"
+                android:name="xyz.nuark.pomslab1.view.fragments.SumFragment"
+                android:layout_width="match_parent"
+                android:layout_height="match_parent"
+                tools:layout="@layout/fragment_sum" />
+
+        </androidx.cardview.widget.CardView>
+    </LinearLayout>
+
+</ScrollView>
--- a/app/src/main/res/layout/activity_result.xml
+++ b/app/src/main/res/layout/activity_result.xml
@ -0,0 +1,45 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".view.activities.ResultActivity">
+
+    <TextView
+        android:id="@+id/historyTitle"
+        android:layout_width="0dp"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="16dp"
+        android:layout_marginTop="16dp"
+        android:layout_marginEnd="16dp"
+        android:text="@string/calculationHistory"
+        android:textSize="20sp"
+        android:textStyle="bold"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintHorizontal_bias="0.0"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent" />
+
+    <androidx.recyclerview.widget.RecyclerView
+        android:id="@+id/historyList"
+        android:layout_width="0dp"
+        android:layout_height="0dp"
+        android:layout_marginStart="16dp"
+        android:layout_marginTop="8dp"
+        android:layout_marginEnd="16dp"
+        android:layout_marginBottom="16dp"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/historyTitle" />
+
+    <TextView
+        android:id="@+id/noHistoryLabel"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:text="@string/noHistory"
+        app:layout_constraintStart_toStartOf="@+id/historyList"
+        app:layout_constraintTop_toTopOf="@+id/historyList" />
+
+</androidx.constraintlayout.widget.ConstraintLayout>
--- a/app/src/main/res/layout/activity_service_communicator.xml
+++ b/app/src/main/res/layout/activity_service_communicator.xml
@ -0,0 +1,164 @@
+<?xml version="1.0" encoding="utf-8"?>
+<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent">
+
+    <androidx.constraintlayout.widget.ConstraintLayout
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        tools:context=".view.activities.ServiceCommunicatorActivity">
+
+        <TextView
+            android:id="@+id/textView2"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:text="@string/hscTitle"
+            android:textSize="20sp"
+            android:textStyle="bold"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toTopOf="parent" />
+
+        <TextView
+            android:id="@+id/textView3"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:text="@string/serviceStatusLabel"
+            android:textSize="16sp"
+            app:layout_constraintBottom_toBottomOf="@+id/serviceController"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toTopOf="@+id/serviceController" />
+
+        <com.google.android.material.chip.Chip
+            android:id="@+id/serviceController"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="8dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:text="@string/serviceStatusStopped"
+            app:chipIcon="@drawable/baseline_stop_24"
+            app:chipIconVisible="true"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintHorizontal_bias="1.0"
+            app:layout_constraintStart_toEndOf="@+id/textView3"
+            app:layout_constraintTop_toBottomOf="@+id/textView2" />
+
+        <Button
+            android:id="@+id/calc"
+            android:layout_width="0dp"
+            android:layout_height="64dp"
+            android:layout_marginStart="8dp"
+            android:layout_marginEnd="16dp"
+            android:text="@string/calculate"
+            app:layout_constraintBottom_toBottomOf="@+id/stepsCount"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintHorizontal_bias="0.5"
+            app:layout_constraintStart_toEndOf="@+id/stepsCount"
+            app:layout_constraintTop_toTopOf="@+id/stepsCount" />
+
+        <com.google.android.material.textfield.TextInputLayout
+            android:id="@+id/stepsCount"
+            style="@style/Widget.Material3.TextInputLayout.OutlinedBox"
+            android:layout_width="0dp"
+            android:layout_height="64dp"
+            android:layout_marginStart="16dp"
+            android:layout_marginEnd="8dp"
+            app:layout_constraintEnd_toStartOf="@+id/calc"
+            app:layout_constraintHorizontal_bias="0.5"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/serviceController">
+
+            <com.google.android.material.textfield.TextInputEditText
+                android:layout_width="match_parent"
+                android:layout_height="match_parent"
+                android:hint="Steps"
+                android:text="200" />
+        </com.google.android.material.textfield.TextInputLayout>
+
+        <TextView
+            android:id="@+id/textView5"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:text="Log"
+            android:textSize="16sp"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintHorizontal_bias="1.0"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/stepsCount" />
+
+        <ScrollView
+            android:id="@+id/logScroller"
+            android:layout_width="0dp"
+            android:layout_height="256dp"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="8dp"
+            android:layout_marginEnd="16dp"
+            android:layout_marginBottom="8dp"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/textView5">
+
+            <TextView
+                android:id="@+id/logHolder"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                tools:text="log" />
+        </ScrollView>
+
+        <TextView
+            android:id="@+id/textView6"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:text="Service file log contents"
+            android:textSize="16sp"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintHorizontal_bias="1.0"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/logScroller" />
+
+        <ScrollView
+            android:id="@+id/serviceLogScroller"
+            android:layout_width="0dp"
+            android:layout_height="256dp"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="8dp"
+            android:layout_marginEnd="16dp"
+            android:layout_marginBottom="8dp"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/textView6">
+
+            <TextView
+                android:id="@+id/serviceLogHolder"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                tools:text="log" />
+        </ScrollView>
+
+        <Button
+            android:id="@+id/readServiceLog"
+            android:layout_width="0dp"
+            android:layout_height="64dp"
+            android:layout_marginStart="8dp"
+            android:layout_marginEnd="16dp"
+            android:text="Read service log"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/serviceLogScroller" />
+
+    </androidx.constraintlayout.widget.ConstraintLayout>
+</ScrollView>
--- a/app/src/main/res/layout/activity_switcher.xml
+++ b/app/src/main/res/layout/activity_switcher.xml
@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".view.activities.SwitcherActivity">
+
+    <androidx.fragment.app.FragmentContainerView
+        android:id="@+id/fragmentHolder"
+        android:layout_width="0dp"
+        android:layout_height="0dp"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent"
+        tools:layout="@layout/fragment_quadratic" />
+
+</androidx.constraintlayout.widget.ConstraintLayout>
--- a/app/src/main/res/layout/calculation_history_item.xml
+++ b/app/src/main/res/layout/calculation_history_item.xml
@ -0,0 +1,80 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.cardview.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:padding="8dp"
+    app:contentPadding="8dp"
+    android:layout_margin="8dp"
+    app:cardCornerRadius="16dp"
+    app:cardElevation="4dp">
+
+    <androidx.constraintlayout.widget.ConstraintLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content">
+
+        <TextView
+            android:id="@+id/datePrev"
+            android:layout_width="wrap_content"
+            android:layout_height="19dp"
+            android:text="@string/dateCHI"
+            android:textStyle="bold"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toTopOf="@+id/dateHolder" />
+
+        <TextView
+            android:id="@+id/dateHolder"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="8dp"
+            android:ellipsize="marquee"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toEndOf="@+id/datePrev"
+            app:layout_constraintTop_toTopOf="parent"
+            tools:text="05.06.2001 16:30" />
+
+        <TextView
+            android:id="@+id/equPrev"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:text="@string/equationCHI"
+            android:textStyle="bold"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toTopOf="@+id/equHolder" />
+
+        <TextView
+            android:id="@+id/equHolder"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="8dp"
+            android:layout_marginTop="8dp"
+            android:ellipsize="marquee"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toEndOf="@+id/equPrev"
+            app:layout_constraintTop_toBottomOf="@+id/dateHolder"
+            tools:text="5x^2+2x-3" />
+
+        <TextView
+            android:id="@+id/resultPrev"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:text="@string/resultCHI"
+            android:textStyle="bold"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toTopOf="@+id/resultHolder" />
+
+        <TextView
+            android:id="@+id/resultHolder"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="8dp"
+            android:layout_marginTop="8dp"
+            android:ellipsize="none"
+            tools:text="x=182"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toEndOf="@+id/resultPrev"
+            app:layout_constraintTop_toBottomOf="@+id/equHolder" />
+    </androidx.constraintlayout.widget.ConstraintLayout>
+</androidx.cardview.widget.CardView>
--- a/app/src/main/res/layout/fragment_quadratic.xml
+++ b/app/src/main/res/layout/fragment_quadratic.xml
@ -0,0 +1,113 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layout>
+
+    <data>
+
+        <variable
+            name="equation"
+            type="xyz.nuark.pomslab1.model.data.QuadraticEquationModel" />
+
+        <variable
+            name="resultString"
+            type="String" />
+    </data>
+
+    <androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+        xmlns:app="http://schemas.android.com/apk/res-auto"
+        xmlns:tools="http://schemas.android.com/tools"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        tools:context=".view.fragments.QuadraticFragment">
+
+        <TextView
+            android:id="@+id/textView"
+            style="@style/TextAppearance.AppCompat.Headline"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:text="@string/title"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toTopOf="parent" />
+
+        <EditText
+            android:id="@+id/aCoef"
+            android:layout_width="0dp"
+            android:layout_height="64dp"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:ems="10"
+            android:hint="@string/a"
+            android:inputType="numberDecimal|numberSigned"
+            android:onTextChanged="@{(cs, s, b, c) -> equation.setAV(cs.toString())}"
+            android:text="@{``+(equation.a ?? ``)}"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/textView" />
+
+        <EditText
+            android:id="@+id/bCoef"
+            android:layout_width="0dp"
+            android:layout_height="64dp"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:ems="10"
+            android:hint="@string/b"
+            android:inputType="numberDecimal|numberSigned"
+            android:onTextChanged="@{(cs, s, b, c) -> equation.setBV(cs.toString())}"
+            android:text="@{``+(equation.b ?? ``)}"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/aCoef" />
+
+        <EditText
+            android:id="@+id/cCoef"
+            android:layout_width="0dp"
+            android:layout_height="64dp"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:ems="10"
+            android:hint="@string/c"
+            android:inputType="numberDecimal|numberSigned"
+            android:onTextChanged="@{(cs, s, b, c) -> equation.setCV(cs.toString())}"
+            android:text="@{``+(equation.c ?? ``)}"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/bCoef" />
+
+        <Button
+            android:id="@+id/button"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:text="@string/calculate"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/cCoef" />
+
+        <TextView
+            android:id="@+id/result"
+            style="@style/TextAppearance.AppCompat.Headline"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:layout_marginBottom="16dp"
+            android:text="@{resultString}"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintHorizontal_bias="0.0"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/button"
+            app:layout_constraintVertical_bias="0.0" />
+
+    </androidx.constraintlayout.widget.ConstraintLayout>
+</layout>
--- a/app/src/main/res/layout/fragment_sum.xml
+++ b/app/src/main/res/layout/fragment_sum.xml
@ -0,0 +1,97 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layout>
+
+    <data>
+
+        <variable
+            name="equation"
+            type="xyz.nuark.pomslab1.model.data.SumModel" />
+
+        <variable
+            name="resultString"
+            type="String" />
+    </data>
+
+    <androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+        xmlns:app="http://schemas.android.com/apk/res-auto"
+        xmlns:tools="http://schemas.android.com/tools"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        tools:context=".view.fragments.SumFragment">
+
+        <TextView
+            android:id="@+id/textView"
+            style="@style/TextAppearance.AppCompat.Headline"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:text="@string/sumTitle"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toTopOf="parent" />
+
+        <EditText
+            android:id="@+id/aCoef"
+            android:layout_width="0dp"
+            android:layout_height="64dp"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:ems="10"
+            android:hint="@string/a"
+            android:inputType="numberDecimal|numberSigned"
+            android:onTextChanged="@{(cs, s, b, c) -> equation.setAV(cs.toString())}"
+            android:text="@{``+(equation.a ?? ``)}"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/textView" />
+
+        <EditText
+            android:id="@+id/bCoef"
+            android:layout_width="0dp"
+            android:layout_height="64dp"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:ems="10"
+            android:hint="@string/b"
+            android:inputType="numberDecimal|numberSigned"
+            android:onTextChanged="@{(cs, s, b, c) -> equation.setBV(cs.toString())}"
+            android:text="@{``+(equation.b ?? ``)}"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/aCoef" />
+
+        <Button
+            android:id="@+id/button"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:text="@string/calculate"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/bCoef" />
+
+        <TextView
+            android:id="@+id/result"
+            style="@style/TextAppearance.AppCompat.Headline"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp"
+            android:layout_marginTop="16dp"
+            android:layout_marginEnd="16dp"
+            android:layout_marginBottom="16dp"
+            android:text="@{resultString}"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintHorizontal_bias="0.0"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/button"
+            app:layout_constraintVertical_bias="0.0" />
+
+    </androidx.constraintlayout.widget.ConstraintLayout>
+</layout>
--- a/app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml
+++ b/app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml
@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@color/ic_launcher_background"/>
+    <foreground android:drawable="@drawable/ic_launcher_foreground"/>
+</adaptive-icon>
--- a/app/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml
+++ b/app/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml
@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@color/ic_launcher_background"/>
+    <foreground android:drawable="@drawable/ic_launcher_foreground"/>
+</adaptive-icon>
--- a/app/src/main/res/mipmap-hdpi/ic_launcher.png
+++ b/app/src/main/res/mipmap-hdpi/ic_launcher.png
--- a/app/src/main/res/mipmap-hdpi/ic_launcher_round.png
+++ b/app/src/main/res/mipmap-hdpi/ic_launcher_round.png
--- a/app/src/main/res/mipmap-mdpi/ic_launcher.png
+++ b/app/src/main/res/mipmap-mdpi/ic_launcher.png
--- a/app/src/main/res/mipmap-mdpi/ic_launcher_round.png
+++ b/app/src/main/res/mipmap-mdpi/ic_launcher_round.png
--- a/app/src/main/res/mipmap-xhdpi/ic_launcher.png
+++ b/app/src/main/res/mipmap-xhdpi/ic_launcher.png
--- a/app/src/main/res/mipmap-xhdpi/ic_launcher_round.png
+++ b/app/src/main/res/mipmap-xhdpi/ic_launcher_round.png
--- a/app/src/main/res/mipmap-xxhdpi/ic_launcher.png
+++ b/app/src/main/res/mipmap-xxhdpi/ic_launcher.png
--- a/app/src/main/res/mipmap-xxhdpi/ic_launcher_round.png
+++ b/app/src/main/res/mipmap-xxhdpi/ic_launcher_round.png
--- a/app/src/main/res/mipmap-xxxhdpi/ic_launcher.png
+++ b/app/src/main/res/mipmap-xxxhdpi/ic_launcher.png
--- a/app/src/main/res/mipmap-xxxhdpi/ic_launcher_round.png
+++ b/app/src/main/res/mipmap-xxxhdpi/ic_launcher_round.png
--- a/app/src/main/res/raw/shining_tractor.png
+++ b/app/src/main/res/raw/shining_tractor.png
--- a/app/src/main/res/values-night/themes.xml
+++ b/app/src/main/res/values-night/themes.xml
@ -0,0 +1,16 @@
+<resources xmlns:tools="http://schemas.android.com/tools">
+    <!-- Base application theme. -->
+    <style name="Theme.PomsLab1" parent="Theme.Material3.DayNight">
+        <!-- Primary brand color. -->
+        <item name="colorPrimary">@color/purple_200</item>
+        <item name="colorPrimaryVariant">@color/purple_700</item>
+        <item name="colorOnPrimary">@color/black</item>
+        <!-- Secondary brand color. -->
+        <item name="colorSecondary">@color/teal_200</item>
+        <item name="colorSecondaryVariant">@color/teal_200</item>
+        <item name="colorOnSecondary">@color/black</item>
+        <!-- Status bar color. -->
+        <item name="android:statusBarColor">?attr/colorPrimaryVariant</item>
+        <!-- Customize your theme here. -->
+    </style>
+</resources>
--- a/app/src/main/res/values-ru/strings.xml
+++ b/app/src/main/res/values-ru/strings.xml
@ -0,0 +1,37 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string name="app_name">ПОМС Лаба</string>
+    <string name="title">Рассчёт корней квадратного уравнения</string>
+    <string name="a">Коэф. A</string>
+    <string name="b">Коэф. B</string>
+    <string name="c">Коэф. C</string>
+    <string name="calculate">Рассчитать</string>
+    <string name="errorInput">Проверьте вводимые данные!</string>
+    <string name="noRoots">Нет корней</string>
+    <string name="openSwitcher">Открыть свитчер</string>
+    <string name="openMultipanel">Открыть мультипанель</string>
+    <string name="switchFragment">Поменять фрагмент</string>
+    <string name="sumTitle">Сумма А и Б</string>
+    <string name="calculationHistory">История вычислений</string>
+    <string name="dateCHI">Дата:</string>
+    <string name="equationCHI">Уравнение:</string>
+    <string name="resultCHI">Результат:</string>
+    <string name="openCalcHistory">Открыть историю вычислений</string>
+    <string name="noHistory">Нет истории</string>
+    <string name="hscTitle">HeavyService коммуникатор</string>
+    <string name="serviceStatusLabel">Статус сервиса</string>
+    <string name="serviceStatusStopped">Остановлен</string>
+    <string name="serviceStatusRunning">Запущен</string>
+    <string name="openHeavyTaskConnector">Открыть HeavyTask коммуникатор</string>
+    <string name="chooseBrowserTitle">Выберите браузер для открытия</string>
+    <string name="switchToDarkLabel">Включить тёмный режим</string>
+    <string name="switchToLightLabel">Включить светлый режим</string>
+    <string name="openActionsLabel">Переходы</string>
+    <string name="openInBrowserLabel">Открыть в браузере</string>
+    <string name="intentContentsLabel">Содержимое Intent</string>
+    <string name="messagePICalculationStarted">"Вычисляем число Пи за "</string>
+    <string name="messagePICalculationEnded">Результат вычисления числа Пи за %d шагов - %f</string>
+    <string name="empty">Пусто</string>
+    <string name="youTriedToOpen">Вы попробовали открыть</string>
+    <string name="openGraphicsActivity">Открыть активити с графикой</string>
+</resources>
--- a/app/src/main/res/values/colors.xml
+++ b/app/src/main/res/values/colors.xml
@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <color name="purple_200">#FFBB86FC</color>
+    <color name="purple_500">#FF6200EE</color>
+    <color name="purple_700">#FF3700B3</color>
+    <color name="teal_200">#FF03DAC5</color>
+    <color name="teal_700">#FF018786</color>
+    <color name="black">#FF000000</color>
+    <color name="white">#FFFFFFFF</color>
+    <color name="red">#EF5350</color>
+    <color name="green">#9CCC65</color>
+</resources>
--- a/app/src/main/res/values/ic_launcher_background.xml
+++ b/app/src/main/res/values/ic_launcher_background.xml
@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <color name="ic_launcher_background">#FFFA01</color>
+</resources>
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@ -0,0 +1,40 @@
+<resources>
+    <string name="app_name">POMS Lab</string>
+    <string name="title">Quadratic equation calculator</string>
+    <string name="a">Coef. A</string>
+    <string name="b">Coef. B</string>
+    <string name="c">Coef. C</string>
+    <string name="calculate">Calculate</string>
+    <string name="errorInput">Check your input!</string>
+    <string name="noRoots">No roots</string>
+    <string name="openSwitcher">Open switcher</string>
+    <string name="openMultipanel">Open multipanel</string>
+    <string name="switchFragment">Switch fragment</string>
+    <string name="sumTitle">Sum of A and B</string>
+    <string name="calculationHistory">Calculation history</string>
+    <string name="dateCHI">Date:</string>
+    <string name="equationCHI">Equation:</string>
+    <string name="resultCHI">Result:</string>
+    <string name="openCalcHistory">Open calc history</string>
+    <string name="noHistory">No history</string>
+    <string name="hscTitle">HeavyService Communicator</string>
+    <string name="serviceStatusLabel">Service status:</string>
+    <string name="serviceStatusStopped">Stopped</string>
+    <string name="serviceStatusRunning">Running</string>
+    <string name="openHeavyTaskConnector">Open HeavyTask connector</string>
+    <string name="chooseBrowserTitle">Chooser your browser</string>
+    <string name="switchToDarkLabel">Switch to dark</string>
+    <string name="switchToLightLabel">Switch to light</string>
+    <string name="openActionsLabel">Open actions</string>
+    <string name="openInBrowserLabel">Open in browser</string>
+    <string name="intentContentsLabel">Intent contents</string>
+    <string name="messagePICalculationStarted">"Started calculating PI for "</string>
+    <string name="messagePICalculationEnded">Result of calculating PI for %d step is %f</string>
+    <string name="empty">Empty</string>
+    <string name="youTriedToOpen">"You tried to open "</string>
+    <string name="openGraphicsActivity">Open Graphics activity</string>
+    <string name="rotate" translatable="false">Rotate</string>
+    <string name="scale" translatable="false">Scale</string>
+    <string name="translate" translatable="false">Translate</string>
+    <string name="alpha" translatable="false">Alpha</string>
+</resources>
--- a/app/src/main/res/values/themes.xml
+++ b/app/src/main/res/values/themes.xml
@ -0,0 +1,16 @@
+<resources xmlns:tools="http://schemas.android.com/tools">
+    <!-- Base application theme. -->
+    <style name="Theme.PomsLab1" parent="Theme.Material3.DayNight">
+        <!-- Primary brand color. -->
+        <item name="colorPrimary">@color/purple_500</item>
+        <item name="colorPrimaryVariant">@color/purple_700</item>
+        <item name="colorOnPrimary">@color/white</item>
+        <!-- Secondary brand color. -->
+        <item name="colorSecondary">@color/teal_200</item>
+        <item name="colorSecondaryVariant">@color/teal_700</item>
+        <item name="colorOnSecondary">@color/black</item>
+        <!-- Status bar color. -->
+        <item name="android:statusBarColor">?attr/colorPrimaryVariant</item>
+        <!-- Customize your theme here. -->
+    </style>
+</resources>
--- a/app/src/main/res/xml/backup_rules.xml
+++ b/app/src/main/res/xml/backup_rules.xml
@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+   Sample backup rules file; uncomment and customize as necessary.
+   See https://developer.android.com/guide/topics/data/autobackup
+   for details.
+   Note: This file is ignored for devices older that API 31
+   See https://developer.android.com/about/versions/12/backup-restore
+-->
+<full-backup-content>
+    <!--
+   <include domain="sharedpref" path="."/>
+   <exclude domain="sharedpref" path="device.xml"/>
+-->
+</full-backup-content>
--- a/app/src/main/res/xml/data_extraction_rules.xml
+++ b/app/src/main/res/xml/data_extraction_rules.xml
@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+   Sample data extraction rules file; uncomment and customize as necessary.
+   See https://developer.android.com/about/versions/12/backup-restore#xml-changes
+   for details.
+-->
+<data-extraction-rules>
+    <cloud-backup>
+        <!-- TODO: Use <include> and <exclude> to control what is backed up.
+        <include .../>
+        <exclude .../>
+        -->
+    </cloud-backup>
+    <!--
+    <device-transfer>
+        <include .../>
+        <exclude .../>
+    </device-transfer>
+    -->
+</data-extraction-rules>
--- a/app/src/test/java/xyz/nuark/pomslab1/ExampleUnitTest.kt
+++ b/app/src/test/java/xyz/nuark/pomslab1/ExampleUnitTest.kt
@ -0,0 +1,17 @@
+package xyz.nuark.pomslab1
+
+import org.junit.Test
+
+import org.junit.Assert.*
+
+/**
+ * Example local unit test, which will execute on the development machine (host).
+ *
+ * See [testing documentation](http://d.android.com/tools/testing).
+ */
+class ExampleUnitTest {
+    @Test
+    fun addition_isCorrect() {
+        assertEquals(4, 2 + 2)
+    }
+}