Otus-Android#2 parallel api calls

Author: AkashevPavel

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

@@ -2,7 +2,9 @@ package otus.homework.coroutines
 
 import kotlinx.coroutines.CancellationException
 import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Deferred
 import kotlinx.coroutines.Job
+import kotlinx.coroutines.async
 import kotlinx.coroutines.launch
 import java.net.SocketTimeoutException
 
@@ -18,15 +20,18 @@ class CatsPresenter(
 ) {
 
     private var _catsView: ICatsView? = null
-    private var _job: Job? = null
+    private var job: Job? = null
 
     fun onInitComplete() {
-        _job = presenterScope.launch {
-            try {
-                val image = imageService.getCatImage().first()
-                val fact = catsService.getCatFact()
+        job = presenterScope.async {
+            val image = async { imageService.getCatImage().first() }
+            val fact = async { catsService.getCatFact() }
 
-                _catsView?.populate(CatsUIState(fact, image))
+            _catsView?.populate(CatsUIState(fact.await(), image.await()))
+        }
+        presenterScope.launch {
+            try {
+                (job as Deferred<*>).await()
             } catch (e: CancellationException) {
                 throw e
             } catch (e: SocketTimeoutException) {
@@ -51,7 +56,7 @@ class CatsPresenter(
     }
 
     fun cancelCoroutine() {
-        _job?.run {
+        job?.run {
             if (isActive) {
                 cancel()
             }

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

@@ -8,14 +8,23 @@ import retrofit2.converter.gson.GsonConverterFactory
 
 class DiContainer {
 
-    private fun buildRetrofit(baseUrl: String) = Retrofit.Builder()
-        .baseUrl(baseUrl)
-        .addConverterFactory(GsonConverterFactory.create())
-        .build()
+    private val converter by lazy { GsonConverterFactory.create() }
 
-    val catsService by lazy { buildRetrofit("https://catfact.ninja/").create(CatsService::class.java) }
+    private fun buildRetrofit(baseUrl: String) =
+        Retrofit.Builder().baseUrl(baseUrl).addConverterFactory(converter)
+            .build()
 
-    val imageService by lazy { buildRetrofit("https://api.thecatapi.com/v1/images/").create(ImageService::class.java) }
+    val catsService by lazy {
+        buildRetrofit("https://catfact.ninja/").create(
+            CatsService::class.java
+        )
+    }
+
+    val imageService by lazy {
+        buildRetrofit("https://api.thecatapi.com/v1/images/").create(
+            ImageService::class.java
+        )
+    }
 
     val presenterScope get() = CoroutineScope(CoroutineName("CatsCoroutine") + Dispatchers.Main)
 }

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

@@ -29,9 +29,9 @@ class MainActivity : AppCompatActivity() {
         if (isFinishing) {
             catsPresenter.apply {
                 detachView()
-                cancelCoroutine()
             }
         }
+        catsPresenter.cancelCoroutine()
         super.onStop()
     }
 }