Initial commit

app/.gitignore

@@ -0,0 +1 @@
+/build

app/build.gradle.kts

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+@file:Suppress("UnstableApiUsage")
+
+@Suppress("DSL_SCOPE_VIOLATION")
+plugins {
+    id(libs.plugins.android.application.get().pluginId)
+    id(libs.plugins.kotlin.android.get().pluginId)
+    id(libs.plugins.kotlin.kapt.get().pluginId)
+    id(libs.plugins.kotlin.parcelize.get().pluginId)
+}
+
+android {
+    defaultConfig {
+        applicationId = "ru.myitschool.lab23"
+        versionCode = 1
+        versionName = "0.0.1"
+
+        targetSdk = 33
+        minSdk = 27
+        compileSdk = 33
+
+        testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
+    }
+
+    lint {
+        warningsAsErrors = true
+        ignoreWarnings = false
+        abortOnError = true
+        checkAllWarnings = true
+        lintConfig = file("lint.xml")
+        lint {
+            disable.addAll(
+                listOf(
+                    "InvalidPackage",
+                    "UnusedIds",
+                    "GradleDependency",
+                    "UnusedResources",
+                    "UnknownNullness",
+                    "SyntheticAccessor",
+                ),
+            )
+        }
+    }
+
+    applicationVariants.all {
+        val lintTask = tasks["lint${name.capitalize()}"]
+        assembleProvider.get().dependsOn.add(lintTask)
+    }
+
+    buildFeatures {
+        viewBinding = true
+    }
+    namespace = "ru.myitschool.lab23"
+}
+
+dependencies {
+
+    implementation(libs.android.material)
+    implementation(libs.androidx.appcompat)
+    implementation(libs.androidx.lifecycle.livedata.ktx)
+    implementation(libs.androidx.lifecycle.viewmodel.ktx)
+    implementation(libs.androidx.core.ktx)
+    implementation(libs.koin.core)
+    implementation(libs.koin.android)
+    implementation(libs.androidx.constraintlayout)
+
+    implementation(libs.androidx.appcompat)
+    implementation(libs.androidx.navigation.fragment)
+    implementation(libs.androidx.navigation.ui)
+
+    // Networking
+    implementation(libs.retrofit.core)
+    implementation(libs.retrofit.kotlin.serialization)
+    implementation(libs.retrofit.converter.gson)
+    implementation(libs.retrofit.converter.jackson)
+    implementation(libs.retrofit.converter.moshi)
+    implementation(libs.retrofit.converter.protobuf)
+    implementation(libs.okhttp.logging)
+    implementation(libs.volley)
+
+    implementation(libs.kotlinx.coroutines.android)
+
+    debugImplementation(libs.leakcanary)
+
+    androidTestImplementation(libs.truth)
+    androidTestImplementation(libs.kakao)
+    androidTestImplementation(libs.androidx.test.uiautomator)
+    androidTestImplementation(libs.androidx.test.ext)
+    androidTestImplementation(libs.androidx.test.runner)
+    androidTestImplementation(libs.androidx.test.rules)
+    androidTestImplementation(libs.androidx.test.espresso.core)
+    androidTestImplementation(libs.androidx.test.espresso.intents)
+    androidTestImplementation(libs.androidx.navigation.testing)
+    androidTestImplementation(libs.androidx.test.ext)
+    androidTestImplementation(libs.androidx.test.rules)
+    androidTestImplementation(libs.androidx.test.espresso.accessibility)
+    androidTestImplementation(libs.kotlinx.coroutines.test)
+    androidTestImplementation(kotlin("test"))
+    testImplementation(libs.androidx.test.ext)
+}

app/lint.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<lint>
+    <issue id="UnusedAttribute" severity="error">
+        <ignore regexp="importantForAutofill"/>
+        <ignore regexp="autofillHints"/>
+    </issue>
+    <issue id="InvalidPackage">
+        <ignore path="**/freemarker-2.*.*.jar" />
+        <ignore path="**/nnio-0.2.jar"/>
+        <ignore path="**/bcpkix-jdk15on-1.69.jar" />
+    </issue>
+
+    <issue id="UnusedResources" severity="error">
+        <ignore regexp="store_short_desc|store_full_desc|store_short_dev_desc|store_full_dev_desc" />
+    </issue>
+
+    <issue id="UnusedResources">
+        <ignore path="**/values-**/strings.xml" />
+        <ignore path="**/values/setup.xml" />
+    </issue>
+
+    <issue id="Typos">
+        <ignore path="**/values-**/strings.xml" />
+        <ignore path="**/values/setup.xml" />
+    </issue>
+
+    <issue id="RestrictedApi" severity="error">
+        <ignore path="build" />
+    </issue>
+
+    <issue id="NewApi" severity="error">
+        <ignore path="build" />
+    </issue>
+
+    <issue id="ObsoleteLintCustomCheck" severity="warning">
+        <ignore path="**/fragment-1.2.5/**/lint.jar" />
+        <ignore path="**/work-runtime-2.**/**/lint.jar" />
+        <ignore path="**/jetified-butterknife-runtime-10.**/**/lint.jar" />
+        <ignore path="**/jetified-dagger-lint-aar-2.**.**/**/lint.jar" />
+        <ignore path="**/jetified-annotation-experimental-1.**/**/lint.jar" />
+        <ignore path="**/jetified-firebase-installations**/**/lint.jar" />
+        <ignore path="**/appcompat-1.**/**/lint.jar" />
+    </issue>
+</lint>

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

app/src/androidTest/java/ru/myitschool/lab23/RateServiceTest.kt

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+package ru.myitschool.lab23
+
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import androidx.test.filters.MediumTest
+import org.junit.FixMethodOrder
+import org.junit.runner.RunWith
+import org.junit.runners.MethodSorters
+
+@RunWith(AndroidJUnit4::class)
+@FixMethodOrder(MethodSorters.NAME_ASCENDING)
+@MediumTest
+class RateServiceTest

app/src/main/AndroidManifest.xml

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+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="ru.myitschool.lab23">
+
+    <uses-permission android:name="android.permission.INTERNET" />
+    <uses-permission android:name="android.permission.POST_NOTIFICATIONS" />
+
+    <application
+        android:allowBackup="true"
+        android:icon="@mipmap/ic_launcher"
+        android:label="@string/app_name"
+        android:roundIcon="@mipmap/ic_launcher_round"
+        android:supportsRtl="true"
+        android:theme="@style/Theme.Lab">
+        <activity
+            android:name=".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>

app/src/main/java/ru/myitschool/lab23/MainActivity.kt

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+package ru.myitschool.lab23
+
+import android.os.Bundle
+import android.view.View
+import android.widget.Button
+import android.widget.EditText
+import android.widget.TextView
+import androidx.appcompat.app.AppCompatActivity
+import androidx.lifecycle.ViewModelProvider
+import com.google.android.material.snackbar.Snackbar
+
+class MainActivity : AppCompatActivity() {
+    lateinit var viewModel: MainViewModel
+    lateinit var textRate: TextView
+    lateinit var textTargetRate: EditText
+    lateinit var rootView: View
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setContentView(R.layout.activity_main)
+
+        initViewModel()
+        initView()
+    }
+
+    fun initViewModel() {
+        viewModel = ViewModelProvider(this).get(MainViewModel::class.java)
+
+        viewModel.usdRate.observe(this) {
+            textRate.text = it
+        }
+
+        viewModel.onCreate()
+    }
+
+    fun initView() {
+        textRate = findViewById(R.id.textUsdRubRate)
+        textTargetRate = findViewById(R.id.textTargetRate)
+        rootView = findViewById(R.id.rootView)
+
+        findViewById<Button>(R.id.btnRefresh).setOnClickListener {
+            viewModel.onRefreshClicked()
+        }
+
+        findViewById<Button>(R.id.btnSubscribeToRate).setOnClickListener {
+            val targetRate = textTargetRate.text.toString()
+            val startRate = viewModel.usdRate.value
+
+            if (targetRate.isNotEmpty() && startRate?.isNotEmpty() == true) {
+                RateCheckService.stopService(this)
+                RateCheckService.startService(this, startRate, targetRate)
+            } else if (targetRate.isEmpty()) {
+                Snackbar.make(rootView, R.string.target_rate_empty, Snackbar.LENGTH_SHORT).show()
+            } else if (startRate.isNullOrEmpty()) {
+                Snackbar.make(rootView, R.string.current_rate_empty, Snackbar.LENGTH_SHORT).show()
+            }
+        }
+    }
+}

app/src/main/java/ru/myitschool/lab23/MainViewModel.kt

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+package ru.myitschool.lab23
+
+import androidx.lifecycle.MutableLiveData
+import androidx.lifecycle.ViewModel
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.GlobalScope
+import kotlinx.coroutines.launch
+
+class MainViewModel : ViewModel() {
+    val usdRate = MutableLiveData<String>()
+    val rateCheckInteractor = RateCheckInteractor()
+
+    fun onCreate() {
+        refreshRate()
+    }
+
+    fun onRefreshClicked() {
+        refreshRate()
+    }
+
+    private fun refreshRate() {
+        GlobalScope.launch(Dispatchers.Main) {
+            val rate = rateCheckInteractor.requestRate()
+            // Log.d(TAG, "usdRate = $rate")
+            usdRate.value = rate
+        }
+    }
+
+    companion object {
+        const val TAG = "MainViewModel"
+        const val USD_RATE_URL = "https://www.freeforexapi.com/api/live?pairs=USDRUB"
+    }
+}

app/src/main/java/ru/myitschool/lab23/NetworkClient.kt

@@ -0,0 +1,41 @@
+package ru.myitschool.lab23
+
+import android.util.Log
+import okhttp3.OkHttpClient
+import okhttp3.Request
+import okhttp3.logging.HttpLoggingInterceptor
+
+class NetworkClient {
+
+    val client = OkHttpClient.Builder()
+        .addInterceptor(
+            HttpLoggingInterceptor().apply {
+                level = HttpLoggingInterceptor.Level.BODY
+            },
+        )
+        .build()
+
+    fun request(url: String): String? {
+        LatestUrl.latestUrl = url
+        LatestUrl.attempts += 1
+        val requestBuilder = Request.Builder()
+            .url(url)
+            .build()
+
+        try {
+            val response = client.newCall(requestBuilder).execute()
+            if (response.isSuccessful) {
+                return response.body?.string()
+            }
+        } catch (e: Exception) {
+            Log.e("NetworkClient", "error during network call", e)
+        }
+
+        return null
+    }
+
+    object LatestUrl {
+        var latestUrl = "Default"
+        var attempts = 0
+    }
+}

app/src/main/java/ru/myitschool/lab23/RateCheckInteractor.kt

@@ -0,0 +1,33 @@
+package ru.myitschool.lab23
+
+import android.util.Log
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
+import org.json.JSONObject
+
+class RateCheckInteractor {
+    val networkClient = NetworkClient()
+
+    suspend fun requestRate(): String {
+        return withContext(Dispatchers.IO) {
+            val result = networkClient.request(MainViewModel.USD_RATE_URL)
+            if (!result.isNullOrEmpty()) {
+                parseRate(result)
+            } else {
+                ""
+            }
+        }
+    }
+
+    private fun parseRate(jsonString: String): String {
+        try {
+            return JSONObject(jsonString)
+                .getJSONObject("rates")
+                .getJSONObject("USDRUB")
+                .getString("rate")
+        } catch (e: Exception) {
+            Log.e("RateCheckInteractor", "", e)
+        }
+        return ""
+    }
+}

app/src/main/java/ru/myitschool/lab23/RateCheckService.kt

@@ -0,0 +1,81 @@
+package ru.myitschool.lab23
+
+import android.app.Service
+import android.content.Context
+import android.content.Intent
+import android.os.Handler
+import android.os.IBinder
+import android.os.Looper
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.GlobalScope
+import kotlinx.coroutines.launch
+import java.math.BigDecimal
+
+class RateCheckService : Service() {
+    val handler = Handler(Looper.getMainLooper())
+    var rateCheckAttempt = 0
+    lateinit var startRate: BigDecimal
+    lateinit var targetRate: BigDecimal
+    val rateCheckInteractor = RateCheckInteractor()
+
+    val rateCheckRunnable: Runnable = Runnable {
+        rateCheckAttempt++
+
+        if (rateCheckAttempt > RATE_CHECK_ATTEMPTS_MAX) {
+        }
+
+        requestAndCheckRate()
+    }
+
+    private fun requestAndCheckRate() {
+        GlobalScope.launch(Dispatchers.Main) {
+            val rate = rateCheckInteractor.requestRate()
+            val rateBigDecimal = BigDecimal(rate)
+            if ((startRate >= targetRate && rateBigDecimal <= targetRate) ||
+                (startRate < targetRate && rateBigDecimal >= targetRate)
+            ) {
+                stopSelf()
+            } else {
+                handler.postDelayed(rateCheckRunnable, RATE_CHECK_INTERVAL)
+            }
+        }
+    }
+
+    override fun onBind(p0: Intent?): IBinder? = null
+
+    override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
+        startRate = BigDecimal(intent?.getStringExtra(ARG_START_RATE))
+        targetRate = BigDecimal(intent?.getStringExtra(ARG_TARGET_RATE))
+
+        handler.post(rateCheckRunnable)
+
+        return START_STICKY
+    }
+
+    override fun onDestroy() {
+        super.onDestroy()
+        handler.removeCallbacks(rateCheckRunnable)
+    }
+
+    companion object {
+        const val TAG = "RateCheckService"
+        const val RATE_CHECK_INTERVAL = 4000L
+        const val RATE_CHECK_ATTEMPTS_MAX = 10
+
+        const val ARG_START_RATE = "ARG_START_RATE"
+        const val ARG_TARGET_RATE = "ARG_TARGET_RATE"
+
+        fun startService(context: Context, startRate: String, targetRate: String) {
+            context.startService(
+                Intent(context, RateCheckService::class.java).apply {
+                    putExtra(ARG_START_RATE, startRate)
+                    putExtra(ARG_TARGET_RATE, targetRate)
+                },
+            )
+        }
+
+        fun stopService(context: Context) {
+            context.stopService(Intent(context, RateCheckService::class.java))
+        }
+    }
+}

app/src/main/res/drawable/ic_launcher_background.xml

@@ -0,0 +1,170 @@
+<?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="#3E91FF"
+        android:pathData="M0,0h108v108h-108z" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M9,0L9,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,0L19,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M29,0L29,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M39,0L39,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M49,0L49,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M59,0L59,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M69,0L69,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M79,0L79,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M89,0L89,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M99,0L99,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,9L108,9"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,19L108,19"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,29L108,29"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,39L108,39"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,49L108,49"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,59L108,59"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,69L108,69"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,79L108,79"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,89L108,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,99L108,99"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,29L89,29"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,39L89,39"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,49L89,49"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,59L89,59"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,69L89,69"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,79L89,79"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M29,19L29,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M39,19L39,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M49,19L49,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M59,19L59,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M69,19L69,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M79,19L79,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+</vector>

app/src/main/res/drawable/ic_launcher_foreground.xml

@@ -0,0 +1,30 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:aapt="http://schemas.android.com/aapt"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportWidth="108"
+    android:viewportHeight="108">
+    <path android:pathData="M31,63.928c0,0 6.4,-11 12.1,-13.1c7.2,-2.6 26,-1.4 26,-1.4l38.1,38.1L107,108.928l-32,-1L31,63.928z">
+        <aapt:attr name="android:fillColor">
+            <gradient
+                android:endX="85.84757"
+                android:endY="92.4963"
+                android:startX="42.9492"
+                android:startY="49.59793"
+                android:type="linear">
+                <item
+                    android:color="#44000000"
+                    android:offset="0.0" />
+                <item
+                    android:color="#00000000"
+                    android:offset="1.0" />
+            </gradient>
+        </aapt:attr>
+    </path>
+    <path
+        android:fillColor="#FFFFFF"
+        android:fillType="nonZero"
+        android:pathData="M65.3,45.828l3.8,-6.6c0.2,-0.4 0.1,-0.9 -0.3,-1.1c-0.4,-0.2 -0.9,-0.1 -1.1,0.3l-3.9,6.7c-6.3,-2.8 -13.4,-2.8 -19.7,0l-3.9,-6.7c-0.2,-0.4 -0.7,-0.5 -1.1,-0.3C38.8,38.328 38.7,38.828 38.9,39.228l3.8,6.6C36.2,49.428 31.7,56.028 31,63.928h46C76.3,56.028 71.8,49.428 65.3,45.828zM43.4,57.328c-0.8,0 -1.5,-0.5 -1.8,-1.2c-0.3,-0.7 -0.1,-1.5 0.4,-2.1c0.5,-0.5 1.4,-0.7 2.1,-0.4c0.7,0.3 1.2,1 1.2,1.8C45.3,56.528 44.5,57.328 43.4,57.328L43.4,57.328zM64.6,57.328c-0.8,0 -1.5,-0.5 -1.8,-1.2s-0.1,-1.5 0.4,-2.1c0.5,-0.5 1.4,-0.7 2.1,-0.4c0.7,0.3 1.2,1 1.2,1.8C66.5,56.528 65.6,57.328 64.6,57.328L64.6,57.328z"
+        android:strokeWidth="1"
+        android:strokeColor="#00000000" />
+</vector>

app/src/main/res/layout/activity_main.xml

@@ -0,0 +1,78 @@
+<?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:id="@+id/rootView"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".MainActivity">
+
+    <TextView
+        android:id="@+id/labelUsdRubRate"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="16dp"
+        android:layout_marginTop="32dp"
+        android:text="@string/usd_rate"
+        android:textAppearance="@style/TextAppearance.AppCompat.Large"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent" />
+
+    <TextView
+        android:id="@+id/textUsdRubRate"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="16dp"
+        android:text="@string/current_rate_empty"
+        android:textAppearance="@style/TextAppearance.AppCompat.Large"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toEndOf="@id/labelUsdRubRate"
+        app:layout_constraintTop_toTopOf="@id/labelUsdRubRate" />
+
+    <Button
+        android:id="@+id/btnRefresh"
+        android:layout_width="0dp"
+        android:layout_height="wrap_content"
+        android:layout_margin="16dp"
+        android:text="@string/refresh_rate"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@id/labelUsdRubRate" />
+
+    <TextView
+        android:id="@+id/labelTargetRate"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="16dp"
+        android:layout_marginTop="16dp"
+        android:text="@string/target_rate"
+        android:textAppearance="@style/TextAppearance.AppCompat.Large"
+        app:layout_constraintBottom_toBottomOf="@id/textTargetRate"
+        app:layout_constraintStart_toStartOf="parent" />
+
+    <EditText
+        android:id="@+id/textTargetRate"
+        android:layout_width="0dp"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="16dp"
+        android:layout_marginTop="32dp"
+        android:layout_marginEnd="16dp"
+        android:gravity="center"
+        android:hint="@string/sample_rate"
+        android:inputType="numberDecimal"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toEndOf="@id/labelTargetRate"
+        app:layout_constraintTop_toBottomOf="@id/btnRefresh"
+        android:importantForAutofill="no" />
+
+    <Button
+        android:id="@+id/btnSubscribeToRate"
+        android:layout_width="0dp"
+        android:layout_height="wrap_content"
+        android:layout_margin="16dp"
+        android:text="@string/subscribe"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@id/textTargetRate" />
+
+</androidx.constraintlayout.widget.ConstraintLayout>

app/src/main/res/values/colors.xml

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <color name="blue_200">#3E91FF</color>
+    <color name="blue_500">#0381FE</color>
+    <color name="blue_700">#0072DE</color>
+    <color name="teal_200">#3E91FF</color>
+    <color name="teal_700">#3E91FF</color>
+    <color name="black">#FF000000</color>
+    <color name="white">#FFFFFFFF</color>
+</resources>

app/src/main/res/values/strings.xml

@@ -0,0 +1,11 @@
+<resources>
+    <string name="app_name">Get Rate</string>
+    <string name="refresh_rate">refresh</string>
+    <string name="usd_rate">Current rate:</string>
+    <string name="target_rate_empty">Target rate is empty</string>
+    <string name="current_rate_empty">Current rate is empty</string>
+    <string name="subscribe">subscribe</string>
+    <string name="target_rate">Target rate</string>
+    <string name="limit_reached">Maximum number of requests reached</string>
+    <string name="sample_rate">75.12</string>
+</resources>

app/src/main/res/values/themes.xml

@@ -0,0 +1,22 @@
+<resources>
+    <!-- Base application theme. -->
+    <style name="Theme.Lab" parent="Theme.Material3.DayNight">
+        <!-- Primary color -->
+        <item name="colorPrimary">@color/blue_500</item>
+        <item name="colorPrimaryVariant">@color/blue_700</item>
+        <item name="colorOnPrimary">@color/white</item>
+        <!-- Secondary color -->
+        <item name="colorSecondary">@color/teal_200</item>
+        <item name="colorSecondaryVariant">@color/teal_700</item>
+        <item name="colorOnSecondary">@color/black</item>
+        <!-- Floating Action Button Container -->
+        <item name="colorPrimaryContainer">@color/blue_500</item>
+        <!--ActionBar -->
+        <item name="colorSurface">@color/blue_700</item>
+        <item name="colorOnSurface">@color/white</item>
+
+        <item name="android:navigationBarColor">@color/blue_200</item>
+        <item name="android:windowLightNavigationBar">true</item>
+    </style>
+
+</resources>

app/src/test/java/ru/myitschool/lab23/ExampleUnitTest.java

@@ -0,0 +1,17 @@
+package ru.myitschool.lab23;
+
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+/**
+ * Example local unit test, which will execute on the development machine (host).
+ *
+ * @see <a href="http://d.android.com/tools/testing">Testing documentation</a>
+ */
+public class ExampleUnitTest {
+    @Test
+    public void addition_isCorrect() {
+        assertEquals(4, 2 + 2);
+    }
+}