Android: implement QMediaPlayer::setPlaybackRate()

Only possible on Android API level 23 or higher.

Task-number: QTBUG-61115
Change-Id: I147575ed0a48f84d4208978a67e0856918e65b3d
Reviewed-by: Alex Blasche <alexander.blasche@qt.io>

5 files changed, 110 insertions, 3 deletions

diff --git a/src/plugins/android/jar/src/org/qtproject/qt5/android/multimedia/QtAndroidMediaPlayer.java b/src/plugins/android/jar/src/org/qtproject/qt5/android/multimedia/QtAndroidMediaPlayer.java
index 7fb4a8690..b1da2f1fa 100644
--- a/src/plugins/android/jar/src/org/qtproject/qt5/android/multimedia/QtAndroidMediaPlayer.java
+++ b/src/plugins/android/jar/src/org/qtproject/qt5/android/multimedia/QtAndroidMediaPlayer.java
@@ -212,6 +212,11 @@ public class QtAndroidMediaPlayer
         mContext = context;
     }
 
+    public MediaPlayer getMediaPlayerHandle()
+    {
+        return mMediaPlayer;
+    }
+
     private void setState(int state)
     {
         if (mState == state)
diff --git a/src/plugins/android/src/mediaplayer/qandroidmediaplayercontrol.cpp b/src/plugins/android/src/mediaplayer/qandroidmediaplayercontrol.cpp
index 7aa7b97b8..df1463a87 100644
--- a/src/plugins/android/src/mediaplayer/qandroidmediaplayercontrol.cpp
+++ b/src/plugins/android/src/mediaplayer/qandroidmediaplayercontrol.cpp
@@ -93,7 +93,9 @@ QAndroidMediaPlayerControl::QAndroidMediaPlayerControl(QObject *parent)
       mPendingVolume(-1),
       mPendingMute(-1),
       mReloadingMedia(false),
-      mActiveStateChangeNotifiers(0)
+      mActiveStateChangeNotifiers(0),
+      mPendingPlaybackRate(1.0),
+      mHasPendingPlaybackRate(false)
 {
     connect(mMediaPlayer,SIGNAL(bufferingChanged(qint32)),
             this,SLOT(onBufferingChanged(qint32)));
@@ -290,12 +292,45 @@ void QAndroidMediaPlayerControl::updateAvailablePlaybackRanges()
 
 qreal QAndroidMediaPlayerControl::playbackRate() const
 {
-    return 1.0f;
+    if (mHasPendingPlaybackRate ||
+            (mState & (AndroidMediaPlayer::Initialized
+                       | AndroidMediaPlayer::Prepared
+                       | AndroidMediaPlayer::Started
+                       | AndroidMediaPlayer::Paused
+                       | AndroidMediaPlayer::PlaybackCompleted
+                       | AndroidMediaPlayer::Error)) == 0) {
+        return mPendingPlaybackRate;
+    }
+
+    return mMediaPlayer->playbackRate();
 }
 
 void QAndroidMediaPlayerControl::setPlaybackRate(qreal rate)
 {
-    Q_UNUSED(rate);
+   if ((mState & (AndroidMediaPlayer::Initialized
+                   | AndroidMediaPlayer::Prepared
+                   | AndroidMediaPlayer::Started
+                   | AndroidMediaPlayer::Paused
+                   | AndroidMediaPlayer::PlaybackCompleted
+                   | AndroidMediaPlayer::Error)) == 0) {
+        if (mPendingPlaybackRate != rate) {
+            mPendingPlaybackRate = rate;
+            mHasPendingPlaybackRate = true;
+            Q_EMIT playbackRateChanged(rate);
+        }
+        return;
+    }
+
+    bool succeeded = mMediaPlayer->setPlaybackRate(rate);
+
+    if (mHasPendingPlaybackRate) {
+        mHasPendingPlaybackRate = false;
+        mPendingPlaybackRate = qreal(1.0);
+        if (!succeeded)
+             Q_EMIT playbackRateChanged(playbackRate());
+    } else if (succeeded) {
+        Q_EMIT playbackRateChanged(rate);
+    }
 }
 
 QMediaContent QAndroidMediaPlayerControl::media() const
@@ -720,6 +755,8 @@ void QAndroidMediaPlayerControl::flushPendingStates()
         setVolume(mPendingVolume);
     if (mPendingMute != -1)
         setMuted((mPendingMute == 1));
+    if (mHasPendingPlaybackRate)
+        setPlaybackRate(mPendingPlaybackRate);
 
     switch (newState) {
     case QMediaPlayer::PlayingState:
diff --git a/src/plugins/android/src/mediaplayer/qandroidmediaplayercontrol.h b/src/plugins/android/src/mediaplayer/qandroidmediaplayercontrol.h
index 04f728a59..119add7f8 100644
--- a/src/plugins/android/src/mediaplayer/qandroidmediaplayercontrol.h
+++ b/src/plugins/android/src/mediaplayer/qandroidmediaplayercontrol.h
@@ -117,6 +117,8 @@ private:
     int mPendingMute;
     bool mReloadingMedia;
     int mActiveStateChangeNotifiers;
+    qreal mPendingPlaybackRate;
+    bool mHasPendingPlaybackRate; // we need this because the rate can theoretically be negative
 
     void setState(QMediaPlayer::State state);
     void setMediaStatus(QMediaPlayer::MediaStatus status);
diff --git a/src/plugins/android/src/wrappers/jni/androidmediaplayer.cpp b/src/plugins/android/src/wrappers/jni/androidmediaplayer.cpp
index 582d8aa9d..b81f98cbd 100644
--- a/src/plugins/android/src/wrappers/jni/androidmediaplayer.cpp
+++ b/src/plugins/android/src/wrappers/jni/androidmediaplayer.cpp
@@ -109,6 +109,33 @@ bool AndroidMediaPlayer::isMuted()
     return mMediaPlayer.callMethod<jboolean>("isMuted");
 }
 
+qreal AndroidMediaPlayer::playbackRate()
+{
+    qreal rate(1.0);
+
+    if (QtAndroidPrivate::androidSdkVersion() < 23)
+        return rate;
+
+    QJNIObjectPrivate player = mMediaPlayer.callObjectMethod("getMediaPlayerHandle", "()Landroid/media/MediaPlayer;");
+    if (player.isValid()) {
+        QJNIObjectPrivate playbackParams = player.callObjectMethod("getPlaybackParams", "()Landroid/media/PlaybackParams;");
+        if (playbackParams.isValid()) {
+            const qreal speed = playbackParams.callMethod<jfloat>("getSpeed", "()F");
+            QJNIEnvironmentPrivate env;
+            if (env->ExceptionCheck()) {
+#ifdef QT_DEBUG
+                env->ExceptionDescribe();
+#endif // QT_DEBUG
+                env->ExceptionClear();
+            } else {
+                rate = speed;
+            }
+        }
+    }
+
+    return rate;
+}
+
 jobject AndroidMediaPlayer::display()
 {
     return mMediaPlayer.callObjectMethod("display", "()Landroid/view/SurfaceHolder;").object();
@@ -155,6 +182,40 @@ void AndroidMediaPlayer::setVolume(int volume)
     mMediaPlayer.callMethod<void>("setVolume", "(I)V", jint(volume));
 }
 
+bool AndroidMediaPlayer::setPlaybackRate(qreal rate)
+{
+    if (QtAndroidPrivate::androidSdkVersion() < 23) {
+        qWarning("Setting the playback rate on a media player requires Android 6.0 (API level 23) or later");
+        return false;
+    }
+
+    QJNIEnvironmentPrivate env;
+
+    QJNIObjectPrivate player = mMediaPlayer.callObjectMethod("getMediaPlayerHandle", "()Landroid/media/MediaPlayer;");
+    if (player.isValid()) {
+        QJNIObjectPrivate playbackParams = player.callObjectMethod("getPlaybackParams", "()Landroid/media/PlaybackParams;");
+        if (playbackParams.isValid()) {
+            playbackParams.callObjectMethod("setSpeed", "(F)Landroid/media/PlaybackParams;", jfloat(rate));
+            // pitch can only be > 0
+            if (!qFuzzyIsNull(rate))
+                playbackParams.callObjectMethod("setPitch", "(F)Landroid/media/PlaybackParams;", jfloat(qAbs(rate)));
+            player.callMethod<void>("setPlaybackParams", "(Landroid/media/PlaybackParams;)V", playbackParams.object());
+            if (Q_UNLIKELY(env->ExceptionCheck())) {
+#ifdef QT_DEBUG
+                env->ExceptionDescribe();
+#endif // QT_DEBUG
+                env->ExceptionClear();
+                qWarning() << "Invalid playback rate" << rate;
+                return false;
+            } else {
+                return true;
+            }
+        }
+    }
+
+    return false;
+}
+
 void AndroidMediaPlayer::setDisplay(AndroidSurfaceTexture *surfaceTexture)
 {
     mMediaPlayer.callMethod<void>("setDisplay",
diff --git a/src/plugins/android/src/wrappers/jni/androidmediaplayer.h b/src/plugins/android/src/wrappers/jni/androidmediaplayer.h
index 28bfa3662..a7284bb0c 100644
--- a/src/plugins/android/src/wrappers/jni/androidmediaplayer.h
+++ b/src/plugins/android/src/wrappers/jni/androidmediaplayer.h
@@ -103,6 +103,7 @@ public:
     bool isPlaying();
     int volume();
     bool isMuted();
+    qreal playbackRate();
     jobject display();
 
     void play();
@@ -113,6 +114,7 @@ public:
     void setDataSource(const QString &path);
     void prepareAsync();
     void setVolume(int volume);
+    bool setPlaybackRate(qreal rate);
     void setDisplay(AndroidSurfaceTexture *surfaceTexture);
 
     static bool initJNI(JNIEnv *env);