播放音乐 上下播放

public class MainActivity extends Activity {

    private MediaPlayer player;
    private MediaPlayer players;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    //第二种方法  添加到sdcard
    //播放
    public void Plays(View v){
        players = new MediaPlayer();
        players.setAudioStreamType(AudioManager.STREAM_MUSIC);//
        try {
            players.setDataSource("/sdcard/people.mp3");
            players.prepare();
            players.start();
        } catch (Exception e) {
            e.printStackTrace();
        }

    }
    //暂停
    public void pause(View v){
        if (players != null && players.isPlaying()) {
            players.pause();
        }else{
            players.start();
        }
    }
    //停止
    public void Stop(View v){
        if (players != null && players.isPlaying()) {
            players.stop();
            players.release();//释放资源
            players=null;
        }
    }


}



                     //实现上一首，下一首

                  public class MainActivity extends Activity {

    private MediaPlayer player;
    private List<String> asList;
    private int count = 0;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        asList = Arrays.asList("/sdcard/ifyou.mp3","/sdcard/people.mp3");
    }



    public void Play(int count) {

        try {
            player = new MediaPlayer();
            player.setAudioStreamType(AudioManager.STREAM_MUSIC);
            player.setDataSource(asList.get(count));
            player.prepare();
            player.start();
        } catch (Exception e) {
            e.printStackTrace();
        }

    }



    // 播放
    public void Action(View v) {
         Play(count);
    }

    // 上一首
    public void Last(View v) {
        if (player != null && player.isPlaying()) {
            if (count <= 0) {
                Toast.makeText(MainActivity.this, "这是第一首", 0).show();
            } else {
                count--;
                Stop();
                Play(count);
            }
        }

    }

    // 下一首
    public void Naxt(View v) {
        if (player != null && player.isPlaying()) {
            if (count < (asList.size()-1)) {
                count++;
                Stop();
                Play(count);
            } else {
                Toast.makeText(MainActivity.this, "这是最后一首", 0).show();
            }
        }
    }

    public void Stop() {
        if (player != null && player.isPlaying()) {
            player.stop();
            player.release();
            player=null;
        }
    }

}