Bug/Feature: Fix audio silence when display is turned off

samples/powerplay/src/main/AndroidManifest.xml

@@ -3,6 +3,7 @@
 
     <uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
     <uses-permission android:name="android.permission.FOREGROUND_SERVICE_MEDIA_PLAYBACK" />
+    <uses-permission android:name="android.permission.POST_NOTIFICATIONS" />
 
     <application
         android:allowBackup="true"

samples/powerplay/src/main/cpp/PowerPlayJNI.cpp

@@ -211,6 +211,18 @@ Java_com_google_oboe_samples_powerplay_engine_PowerPlayAudioPlayer_stopPlayingNa
     player.triggerUp(index);
 }
 
+/**
+ * Native (JNI) implementation of PowerPlayAudioPlayer.updatePerformanceModeNative()
+ */
+JNIEXPORT void JNICALL
+Java_com_google_oboe_samples_powerplay_engine_PowerPlayAudioPlayer_updatePerformanceModeNative(
+        JNIEnv *env,
+        jobject,
+        jobject mode) {
+    auto performanceMode = getPerformanceMode(env, mode);
+    player.updatePerformanceMode(performanceMode);
+}
+
 /**
  * Native (JNI) implementation of PowerPlayAudioPlayer.setLoopingNative()
  */

samples/powerplay/src/main/cpp/PowerPlayMultiPlayer.cpp

@@ -132,22 +132,7 @@ void PowerPlayMultiPlayer::triggerDown(int32_t index, oboe::PerformanceMode perf
         return;
     }
 
-    // If the performance mode has changed, we need to reopen the stream.
-    // Also reopen if the user has changed the MMAP policy (enabled/disabled) since the stream was opened.
-    if (performanceMode != mLastPerformanceMode ||
-        isMMapEnabled() != mLastMMapEnabled) {
-        teardownAudioStream();
-
-        // Attempt here to reopen the stream with the new performance mode.
-        const auto result = openStream(performanceMode);
-        if (!result) {
-            // Something went wrong and the stream could not be reopened.
-            __android_log_print(ANDROID_LOG_ERROR,
-                                TAG,
-                                "Failed to reopen stream with new performance mode");
-            return;
-        }
-    }
+    updatePerformanceMode(performanceMode);
 
     // Assure previous sample is stopped and the play head is reset to zero, avoiding the
     // currently playing index. Only allow the playback head to reset when the song has changed.
@@ -184,6 +169,16 @@ void PowerPlayMultiPlayer::triggerDown(int32_t index, oboe::PerformanceMode perf
     }
 }
 
+void PowerPlayMultiPlayer::updatePerformanceMode(oboe::PerformanceMode performanceMode) {
+    if (performanceMode != mLastPerformanceMode ||
+        isMMapEnabled() != mLastMMapEnabled) {
+
+        __android_log_print(ANDROID_LOG_INFO, TAG, "updatePerformanceMode: Reopening stream");
+        teardownAudioStream();
+        openStream(performanceMode);
+    }
+}
+
 bool PowerPlayMultiPlayer::setMMapEnabled(bool enabled) {
     auto result = oboe::OboeExtensions::setMMapEnabled(enabled);
     return result == 0;

samples/powerplay/src/main/cpp/PowerPlayMultiPlayer.h

@@ -36,14 +36,14 @@ class PowerPlayMultiPlayer : public iolib::SimpleMultiPlayer {
 
     void triggerDown(int32_t index, oboe::PerformanceMode performanceMode) override;
 
+    void updatePerformanceMode(oboe::PerformanceMode performanceMode);
+
     static bool setMMapEnabled(bool enabled);
 
     static bool isMMapEnabled();
 
     static bool isMMapSupported();
 
-    bool isMMapUsed();
-
     int32_t getCurrentlyPlayingIndex();
 
     int32_t setBufferSizeInFrames(int32_t bufferSizeInFrames);