Add missing PlayerView lifecycle handling (PiP #1)

CHANGELOG.md

@@ -5,6 +5,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/),
 and this project adheres to [Semantic Versioning](https://semver.org/).
 
 ## [Unreleased]
+### Fixed
+
+- Android: Playback doesn't pause when app goes to background
 
 ## [0.4.0] - 2023-12-12
 ### Added

android/src/main/kotlin/com/bitmovin/player/flutter/FlutterPlayerView.kt

@@ -2,9 +2,12 @@ package com.bitmovin.player.flutter
 
 import android.content.Context
 import android.view.View
+import androidx.lifecycle.DefaultLifecycleObserver
+import androidx.lifecycle.LifecycleOwner
 import com.bitmovin.player.PlayerView
-import com.bitmovin.player.api.Player
 import com.bitmovin.player.flutter.json.JPlayerViewCreateArgs
+import io.flutter.embedding.android.FlutterActivity
+import io.flutter.embedding.android.FlutterFragmentActivity
 import io.flutter.plugin.common.BinaryMessenger
 import io.flutter.plugin.common.EventChannel
 import io.flutter.plugin.common.MethodCall
@@ -22,7 +25,6 @@ class FlutterPlayerView(
     id: Int,
     args: Any?,
 ) : MethodChannel.MethodCallHandler, EventChannel.StreamHandler, PlatformView, EventListener() {
-    private val playerView: PlayerView
     private val methodChannel: MethodChannel =
         MethodChannel(
             messenger,
@@ -35,10 +37,33 @@ class FlutterPlayerView(
             messenger,
         )
 
+    private val activity = context.requireActivity()
+    private val playerView: PlayerView = PlayerView(context, player = null)
+
+    private val activityLifecycle =
+        activity.let { it as? FlutterActivity ?: it as? FlutterFragmentActivity }
+            ?.lifecycle
+            ?: error(
+                "Trying to create an instance of ${this::class.simpleName}" +
+                    " while not attached to a FlutterActivity or FlutterFragmentActivity",
+            )
+
+    private val activityLifecycleObserver =
+        object : DefaultLifecycleObserver {
+            override fun onStart(owner: LifecycleOwner) = playerView.onStart()
+
+            override fun onResume(owner: LifecycleOwner) = playerView.onResume()
+
+            override fun onPause(owner: LifecycleOwner) = playerView.onPause()
+
+            override fun onStop(owner: LifecycleOwner) = playerView.onStop()
+
+            override fun onDestroy(owner: LifecycleOwner) = dispose()
+        }
+
     init {
         val playerViewCreateArgs = JPlayerViewCreateArgs(args as Map<*, *>)
 
-        playerView = PlayerView(context, null as Player?)
         PlayerManager.onPlayerCreated(playerViewCreateArgs.playerId) { player ->
             playerView.player = player
             if (playerViewCreateArgs.hasFullscreenHandler) {
@@ -50,6 +75,8 @@ class FlutterPlayerView(
                 )
             }
         }
+
+        activityLifecycle.addObserver(activityLifecycleObserver)
     }
 
     override fun onMethodCall(
@@ -58,7 +85,7 @@ class FlutterPlayerView(
     ) = when (call.method) {
         Methods.ENTER_FULLSCREEN -> playerView.enterFullscreen()
         Methods.EXIT_FULLSCREEN -> playerView.exitFullscreen()
-        Methods.DESTROY_PLAYER_VIEW -> { /* no-op */ }
+        Methods.DESTROY_PLAYER_VIEW -> Unit // no-op
         else -> throw NotImplementedError()
     }
 
@@ -69,6 +96,7 @@ class FlutterPlayerView(
         playerView.onDestroy()
         methodChannel.setMethodCallHandler(null)
         eventChannel.setStreamHandler(null)
+        activityLifecycle.removeObserver(activityLifecycleObserver)
     }
 
     override fun onListen(

android/src/main/kotlin/com/bitmovin/player/flutter/Util.kt

@@ -1,5 +1,8 @@
 package com.bitmovin.player.flutter
 
+import android.app.Activity
+import android.content.Context
+import android.content.ContextWrapper
 import android.os.Handler
 import android.os.Looper
 
@@ -25,3 +28,10 @@ inline fun postToMainThread(crossinline block: () -> Unit?) {
         block()
     }
 }
+
+fun Context.requireActivity(): Activity =
+    when (this) {
+        is Activity -> this
+        is ContextWrapper -> baseContext.requireActivity()
+        else -> error("No activity found for context $this")
+    }