Android：音乐播放器（2）—加进度条

加进度条

MainActivity代码如下：

public class Main3Activity extends AppCompatActivity {
    private Button start,end,pause;
    MediaPlayer mediaPlayer;
    private SeekBar seekBar;
    Timer timer = new Timer();;
    TimerTask timerTask;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main3);

        start = (Button) findViewById(R.id.start);
        end = (Button) findViewById(R.id.end);
        pause = (Button) findViewById(R.id.pause);
        seekBar = (SeekBar) findViewById(R.id.seekBar);



        Intent intent = getIntent();
        String url = intent.getStringExtra("url");
        // mediaPlayer = MediaPlayer.create(Main3Activity.this, Uri.parse(url));
        mediaPlayer = MediaPlayer.create(Main3Activity.this,R.raw.a);

        //歌曲的播放时长
        seekBar.setMax(mediaPlayer.getDuration());

        seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
            @Override
            public void onProgressChanged(SeekBar seekBar, int i, boolean b) {

            }

            @Override
            public void onStartTrackingTouch(SeekBar seekBar) {
                Log.i("messgae","start");

            }

            @Override
            public void onStopTrackingTouch(SeekBar seekBar) {
                Log.i("messgae","stop");

                //设置歌曲的进度为进度条的位置
                mediaPlayer.seekTo(seekBar.getProgress());

            }
        });
    }

    public void click(View view){

        int id = view.getId();

        switch(id){
            case R.id.start:
                start();

                break;
            case R.id.end:

                stop();

                break;
            case R.id.pause:
                pause();
                break;
        }
    }
    public void start(){
        mediaPlayer.start();
        timerTask = new TimerTask() {
            @Override
            public void run() {
                //歌曲当前播放位置
                seekBar.setProgress(mediaPlayer.getCurrentPosition());
            }
        };

        //1.等多久再执行什么
        //2.每隔多久执行一次什么
        timer.schedule(timerTask,0,100);


        start.setEnabled(false);
    }
    public void pause(){
        String pause1 = pause.getText().toString().trim();
        if("暂停".equals(pause1)){
            mediaPlayer.pause();
            pause.setText("继续");
        }else{
            mediaPlayer.start();
            pause.setText("暂停");
        }


    }
    public void stop(){
        if(mediaPlayer!=null){
            timer.cancel();
            mediaPlayer.stop();
            mediaPlayer.release();
            mediaPlayer = null;
            start.setEnabled(true);
        }
    }
}