Homework

app/build.gradle

@@ -41,4 +41,7 @@ dependencies {
     implementation 'com.google.android.material:material:1.11.0'
     implementation 'androidx.constraintlayout:constraintlayout:2.1.4'
     implementation 'com.squareup.picasso:picasso:2.71828'
+    implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-core:1.7.3'
+    implementation "androidx.lifecycle:lifecycle-viewmodel-ktx:2.6.1"
+    implementation "androidx.activity:activity-ktx:1.7.2"
 }

app/src/main/java/otus/homework/coroutines/CatsService.kt

@@ -1,10 +1,10 @@
 package otus.homework.coroutines
 
-import retrofit2.Call
+import retrofit2.Response
 import retrofit2.http.GET
 
 interface CatsService {
 
     @GET("fact")
-    fun getCatFact() : Call<Fact>
+    suspend fun getCatFact(): Response<FactDto>
 }

app/src/main/java/otus/homework/coroutines/CatsView.kt

@@ -2,31 +2,24 @@ package otus.homework.coroutines
 
 import android.content.Context
 import android.util.AttributeSet
-import android.widget.Button
+import android.widget.ImageView
 import android.widget.TextView
+import android.widget.Toast
 import androidx.constraintlayout.widget.ConstraintLayout
+import com.squareup.picasso.Picasso
 
 class CatsView @JvmOverloads constructor(
     context: Context,
     attrs: AttributeSet? = null,
     defStyleAttr: Int = 0
-) : ConstraintLayout(context, attrs, defStyleAttr), ICatsView {
+) : ConstraintLayout(context, attrs, defStyleAttr) {
 
-    var presenter :CatsPresenter? = null
-
-    override fun onFinishInflate() {
-        super.onFinishInflate()
-        findViewById<Button>(R.id.button).setOnClickListener {
-            presenter?.onInitComplete()
-        }
+    fun populate(dataModel: DataModel) {
+        findViewById<TextView>(R.id.fact_textView).text = dataModel.fact
+        Picasso.get().load(dataModel.imageUrl).into(findViewById<ImageView>(R.id.image))
     }
 
-    override fun populate(fact: Fact) {
-        findViewById<TextView>(R.id.fact_textView).text = fact.fact
+    fun showToast(text: String) {
+        Toast.makeText(context, text, Toast.LENGTH_SHORT).show()
     }
-}
-
-interface ICatsView {
-
-    fun populate(fact: Fact)
 }

app/src/main/java/otus/homework/coroutines/CatsViewModel.kt

@@ -0,0 +1,69 @@
+package otus.homework.coroutines
+
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.ViewModelProvider
+import androidx.lifecycle.viewModelScope
+import kotlinx.coroutines.CoroutineExceptionHandler
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.async
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.launch
+import java.net.SocketTimeoutException
+
+
+class CatsViewModel(
+    private val catsService: CatsService,
+    private val imageService: ImageService
+) : ViewModel() {
+
+    private val _state = MutableStateFlow<Result>(Result.Initialization)
+    val state = _state.asStateFlow()
+
+    private var job: Job? = null
+
+    private val exceptionHandler by lazy {
+        CoroutineExceptionHandler { _, throwable ->
+            if (throwable is SocketTimeoutException) {
+                showToast("Не удалось получить ответ от сервером")
+            } else {
+                showToast(throwable.message ?: "No message")
+                CrashMonitor.trackWarning(throwable)
+            }
+        }
+    }
+
+    fun onInitComplete() {
+        job?.cancel()
+        job = viewModelScope.launch(exceptionHandler) {
+            val factDeferred = async { catsService.getCatFact().body()?.fact }
+            val imageDeferred = async { imageService.getImage().body()?.getOrNull(0)?.url }
+
+            val fact = factDeferred.await()
+            val image = imageDeferred.await()
+
+            if (!fact.isNullOrEmpty() && !image.isNullOrEmpty()) {
+                _state.emit(Result.Success(DataModel(fact.toString(), image)))
+            }
+        }
+    }
+
+    private fun showToast(text: String) {
+        viewModelScope.launch {
+            _state.emit(Result.Error(text))
+        }
+    }
+
+    class CatsViewModelFactory(
+        private val catsService: CatsService,
+        private val imageService: ImageService
+    ) : ViewModelProvider.Factory {
+        override fun <T : ViewModel> create(modelClass: Class<T>): T {
+            if (modelClass.isAssignableFrom(CatsViewModel::class.java)) {
+                @Suppress("UNCHECKED_CAST")
+                return CatsViewModel(catsService, imageService) as T
+            }
+            throw IllegalArgumentException("Unknown ViewModel class")
+        }
+    }
+}

app/src/main/java/otus/homework/coroutines/CrashMonitor.kt

@@ -1,10 +1,13 @@
 package otus.homework.coroutines
 
+import android.util.Log
+
 object CrashMonitor {
 
     /**
      * Pretend this is Crashlytics/AppCenter
      */
-    fun trackWarning() {
+    fun trackWarning(t: Throwable) {
+        Log.d("CatsApp", t.toString())
     }
 }

app/src/main/java/otus/homework/coroutines/DataModel.kt

@@ -0,0 +1,6 @@
+package otus.homework.coroutines
+
+data class DataModel(
+    val fact: String,
+    val imageUrl: String
+)

app/src/main/java/otus/homework/coroutines/DiContainer.kt

@@ -5,12 +5,21 @@ import retrofit2.converter.gson.GsonConverterFactory
 
 class DiContainer {
 
-    private val retrofit by lazy {
+    private val catsRetrofit by lazy {
         Retrofit.Builder()
             .baseUrl("https://catfact.ninja/")
             .addConverterFactory(GsonConverterFactory.create())
             .build()
     }
 
-    val service by lazy { retrofit.create(CatsService::class.java) }
-}
+    private val imageRetrofit by lazy {
+        Retrofit.Builder()
+            .baseUrl("https://api.thecatapi.com/")
+            .addConverterFactory(GsonConverterFactory.create())
+            .build()
+    }
+
+    val catsService: CatsService by lazy { catsRetrofit.create(CatsService::class.java) }
+
+    val imageService: ImageService by lazy { imageRetrofit.create(ImageService::class.java) }
+}

app/src/main/java/otus/homework/coroutines/Dto.kt

@@ -0,0 +1,12 @@
+package otus.homework.coroutines
+
+import com.google.gson.annotations.SerializedName
+
+data class FactDto(
+    @SerializedName("fact") val fact: String,
+    @SerializedName("length") val length: Int
+)
+
+data class ImageDto(
+    @SerializedName("url") var url: String
+)

app/src/main/java/otus/homework/coroutines/ImageService.kt

@@ -0,0 +1,10 @@
+package otus.homework.coroutines
+
+import retrofit2.Response
+import retrofit2.http.GET
+
+interface ImageService {
+
+    @GET("v1/images/search/")
+    suspend fun getImage(): Response<List<ImageDto>>
+}

app/src/main/java/otus/homework/coroutines/MainActivity.kt

@@ -2,10 +2,18 @@ package otus.homework.coroutines
 
 import androidx.appcompat.app.AppCompatActivity
 import android.os.Bundle
+import android.widget.Button
+import androidx.activity.viewModels
+import androidx.lifecycle.Lifecycle
+import androidx.lifecycle.lifecycleScope
+import androidx.lifecycle.repeatOnLifecycle
+import kotlinx.coroutines.launch
 
 class MainActivity : AppCompatActivity() {
 
-    lateinit var catsPresenter: CatsPresenter
+    private val viewModel: CatsViewModel by viewModels {
+        CatsViewModel.CatsViewModelFactory(diContainer.catsService, diContainer.imageService)
+    }
 
     private val diContainer = DiContainer()
 
@@ -14,17 +22,20 @@ class MainActivity : AppCompatActivity() {
 
         val view = layoutInflater.inflate(R.layout.activity_main, null) as CatsView
         setContentView(view)
-
-        catsPresenter = CatsPresenter(diContainer.service)
-        view.presenter = catsPresenter
-        catsPresenter.attachView(view)
-        catsPresenter.onInitComplete()
-    }
-
-    override fun onStop() {
-        if (isFinishing) {
-            catsPresenter.detachView()
+        viewModel.onInitComplete()
+        findViewById<Button>(R.id.button).setOnClickListener {
+            viewModel.onInitComplete()
+        }
+        lifecycleScope.launch {
+            repeatOnLifecycle(Lifecycle.State.STARTED) {
+                viewModel.state.collect { state ->
+                    when (state) {
+                        is Result.Initialization -> Unit
+                        is Result.Success -> view.populate(state.dataModel)
+                        is Result.Error -> view.showToast(state.text)
+                    }
+                }
+            }
         }
-        super.onStop()
     }
-}
+}

app/src/main/java/otus/homework/coroutines/Result.kt

@@ -0,0 +1,7 @@
+package otus.homework.coroutines
+
+sealed class Result {
+    object Initialization : Result()
+    data class Success(val dataModel: DataModel) : Result()
+    data class Error(val text: String) : Result()
+}

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

@@ -3,28 +3,38 @@
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
-    android:padding="16dp"
     android:layout_height="match_parent"
+    android:padding="16dp"
     tools:context=".MainActivity">
 
-    <TextView
-        android:id="@+id/fact_textView"
-        android:textColor="@color/black"
-        android:textSize="24sp"
-        android:layout_width="wrap_content"
-        android:layout_height="wrap_content"
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:orientation="vertical"
         app:layout_constraintBottom_toBottomOf="parent"
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintStart_toStartOf="parent"
-        app:layout_constraintTop_toTopOf="parent" />
+        app:layout_constraintTop_toTopOf="parent">
+
+        <ImageView
+            android:id="@+id/image"
+            android:layout_width="match_parent"
+            android:layout_height="200dp" />
+
+        <TextView
+            android:id="@+id/fact_textView"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:textColor="@color/black"
+            android:textSize="24sp" />
+
+        <Button
+            android:id="@+id/button"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:text="@string/more_facts"
+            app:layout_constraintTop_toBottomOf="@+id/fact_textView" />
+    </LinearLayout>
 
-    <Button
-        android:id="@+id/button"
-        android:layout_width="wrap_content"
-        android:layout_height="wrap_content"
-        android:text="@string/more_facts"
-        app:layout_constraintEnd_toEndOf="parent"
-        app:layout_constraintStart_toStartOf="parent"
-        app:layout_constraintTop_toBottomOf="@+id/fact_textView" />
 
 </otus.homework.coroutines.CatsView>