Question

在我的音乐播放器中，如果一首歌曲已经在播放，并且用户单击另一首歌曲，则该歌曲也会开始播放。换句话说，一次播放多首歌曲确实很烦人。我一次想要一首歌。这意味着，如果一首歌曲已经在播放，并且用户单击另一首歌曲，则前一首歌曲将停止播放，而被点击的歌曲将播放。

java代码

  public void onItemClick(final Button b, View view, final SongInfo obj, int position) {


                if(b.getText().equals("Stop")){
                    mediaPlayer.stop();
                    mediaPlayer.reset();
                    mediaPlayer.release();
                    mediaPlayer = null;
                    b.setText("Play");
                }
                else {

                    Runnable runnable = new Runnable() {
                        @Override
                        public void run() {
                            try {
                                mediaPlayer = new MediaPlayer();
                                mediaPlayer.setDataSource(obj.getSongUrl());
                                mediaPlayer.prepareAsync();
                                mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
                                    @Override
                                    public void onPrepared(MediaPlayer mp) {
                                        mediaPlayer.start();
                                        seekBar.setProgress(0);
                                        seekBar.setMax(mediaPlayer.getDuration());
                                        Log.d("Prog", "run: " + mediaPlayer.getDuration());
                                    }
                                });
                                b.setText("Stop");
                                }catch (Exception e){}
                        }

                    };
                    myHandler.postDelayed(runnable,100);

                }
            }
        });
        checkUserPermission();
        Thread t = new runThread();
        t.start();
    }




    //Thread method for seek bar
    public class runThread extends Thread {
        @Override
        public void run() {
            while (true) {

                try {
                    Thread.sleep(1000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                Log.d("Runwa", "run: " + 1);
                if (mediaPlayer != null) {
                    seekBar.post(new Runnable() {
                        @Override
                        public void run() {
                            seekBar.setProgress(mediaPlayer.getCurrentPosition());
                        }
                    });

                    Log.d("Runwa", "run: " + mediaPlayer.getCurrentPosition());
                }
            }
        }

    }

Answer 1

if("STOP".equalsIgnoreCase(b.getText()) {
    mediaPlayer.stop()  // stop the media player
    mediaPlayer.reset() // reset media player for re-use
    b.setText("Play");  // to re-play song
} else {
    // use the same instance of media-player if want to play single song at a time
    mediaPlayer.setDataSource(obj.getSongUrl());
    mediaPlayer.prepare(); // can use prepareAsync() also
    mediaPlayer.start();
    b.setText("Stop");
}

要一次只播放一首歌曲，则必须始终使用mediaPlayer对象的相同实例。（请参阅内嵌评论）

Ref：Media Player State Diagram

我如何在android studio中一次播放一首歌

1 个答案: