java - 设置媒体 Controller

Question

我正在尝试设置 MediaController，以便在播放音频时可以进行控制，但是当我尝试声明它时，“this”将作为错误出现。我做错了什么？

@TargetApi(Build.VERSION_CODES.LOLLIPOP)公共(public)类 MainActivity 扩展 AppCompatActivity 实现 MediaRecorder.OnInfoListener {

private boolean cont;
private MediaRecorder mediaRecorder;
private MediaPlayer mediaPlayer;
private String OUTPUT_FILE;
private MediaController mediaController;




@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    OUTPUT_FILE = Environment.getExternalStorageDirectory()+"/androidaudio1.3gpp";
    cont=true;


}



public void buttonClicked(View view){


    switch (view.getId()){

        case R.id.startRec:
            beginRecord();
            break;

        case R.id.stopRec:
            stopRecord();
            break;

        case R.id.startPlay:
            try {
                begginPlaying();
            } catch (IOException e) {
                e.printStackTrace();
            }
            break;

        case R.id.stopPlay:
                stopPlaying();
            break;


    }
}


@TargetApi(Build.VERSION_CODES.LOLLIPOP)
private void begginPlaying() throws IOException {

    if (mediaPlayer != null)
        mediaPlayer.release();

    mediaPlayer = new MediaPlayer();
    mediaPlayer.setDataSource(OUTPUT_FILE);

    mediaController = new MediaController(this);
    mediaController.setMediaPlayer(this);

    mediaController.show();

    mediaPlayer.prepare();
    mediaPlayer.start();


}


private void stopPlaying(){

    if (mediaPlayer!= null){

        mediaPlayer.stop();
        mediaPlayer.reset();
        mediaPlayer.release();
        mediaPlayer=null;
    }


@Override
public void start() {
    mediaPlayer.start();

}

@Override
public void pause() {
    mediaPlayer.pause();

}

@Override
public int getDuration() {
    return mediaPlayer.getDuration();
}

@Override
public int getCurrentPosition() {
    return mediaPlayer.getCurrentPosition();
}

@Override
public void seekTo(int pos) {
    mediaPlayer.seekTo(pos);
}

@Override
public boolean isPlaying() {
    return mediaPlayer.isPlaying();
}

@Override
public int getBufferPercentage() {
    return 0;
}

@Override
public boolean canPause() {
    return true;
}

@Override
public boolean canSeekBackward() {
    return true;
}

@Override
public boolean canSeekForward() {
    return true;
}

@Override
public int getAudioSessionId() {
    return 0;
}

}

Answer 1

MediaController 需要将上下文传递给构造函数。如果没有更多代码或不知道在哪里声明 MediaController，我最好的猜测是您无权访问声明 MediaController 的位置的上下文。从您想要使用 MediaController 的 Activity 传递上下文，或者将此代码放入该 Activity 中。

https://developer.android.com/reference/android/widget/MediaController.html

编辑:

我尝试了你的代码，检查你的导入并确保你有，导入android.widget.MediaController而不是导入android.media.session.MediaController。