如何播放下一首歌曲的随机歌曲[重复]

Posted 2021-04-14

这个问题在这里已有答案：

• Play list of mp3 file with MediaPlayer in Android 2回答

我有一系列歌曲，我的应用程序在活动打开时随机播放歌曲但是当歌曲结束时我想播放阵列中的另一首随机歌曲，有人可以帮忙吗？

public MediaPlayer mediaPlayer;
private int songs[];

songs = new int[] {
    R.raw.track1,
    R.raw.track2,
    R.raw.track3,
    R.raw.track4,
    R.raw.track5,
    R.raw.track6,
    R.raw.track7,
    R.raw.track8,
    R.raw.track9,
    R.raw.track10,
    R.raw.track11,
    R.raw.track12,
    R.raw.track13,
    R.raw.track14,
    R.raw.track15,
    R.raw.track16,
    R.raw.track17,
};


int randomSong =  new Random().nextInt(songs.length);
mediaPlayer = MediaPlayer.create(this, songs[randomSong]);
mediaPlayer.start();

答案

你需要设置一个completion listener：

mediaPlayer.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
    void onCompletion(MediaPlayer mp) {
        // Play next song
    }
});

另一答案

试试这个，你需要在你的活动中实现MediaPlayer.OnCompletionListener接口

public class MainActivity extends AppCompatActivity implements MediaPlayer.OnCompletionListener {
    private MediaPlayer mediaPlayer;
    private int songs[];
    private int randomSong;
    private Random random = new Random();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mediaPlayer.setOnCompletionListener(this);
        songs = new int[]{
                R.raw.track1,
                R.raw.track2,
                R.raw.track3,
                R.raw.track4,
                R.raw.track5,
                R.raw.track6,
                R.raw.track7,
                R.raw.track8,
                R.raw.track9,
                R.raw.track10,
                R.raw.track11,
                R.raw.track12,
                R.raw.track13,
                R.raw.track14,
                R.raw.track15,
                R.raw.track16,
                R.raw.track17,
        };


        randomSong = getRandom(songs);
        mediaPlayer = MediaPlayer.create(this, songs[randomSong]);
        mediaPlayer.start();
    }

    @Override
    public void onCompletion(MediaPlayer mediaPlayer) {
        randomSong = getRandom(songs);
        mediaPlayer = MediaPlayer.create(this, songs[randomSong]);
        mediaPlayer.start();
    }

    public int getRandom(int[] array) {
        return random.nextInt(array.length);
    }
}

另一答案

您可以使用侦听器在歌曲播放完毕后运行回调：

setOnCompletionListener(MediaPlayer.OnCompletionListener listener)

另外，为了确保随机性，我强烈建议每次需要随机数时不要使用新的Random对象。相反，声明一个变量random并将其用于所有随机需求。