編輯:關於android開發
在前面的項目中添加SeekBar
<SeekBar
android:id="@+id/sb"
android:layout_width="match_parent"
android:layout_height="wrap_content" />

相關的代碼如下:
public class MainActivity extends Activity implements OnClickListener {
private EditText et_path;
private Button bt_play, bt_replay, bt_pause, bt_stop;
private SurfaceView sv;
private SeekBar sb;
private MediaPlayer mediaPlayer;
private int currentPosition;
private Boolean isplaying;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
sv = (SurfaceView) findViewById(R.id.sv);
et_path = (EditText) findViewById(R.id.et_path);
bt_play = (Button) findViewById(R.id.bt_play);
bt_replay = (Button) findViewById(R.id.bt_replay);
bt_pause = (Button) findViewById(R.id.bt_pause);
bt_stop = (Button) findViewById(R.id.bt_stop);
sb = (SeekBar) findViewById(R.id.sb);
sb.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
int process = seekBar.getProgress();
if(mediaPlayer != null && mediaPlayer.isPlaying()) {
mediaPlayer.seekTo(process);
}
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
@Override
public void onProgressChanged(SeekBar seekBar, int progress,
boolean fromUser) {
// TODO Auto-generated method stub
}
});
bt_pause.setOnClickListener(this);
bt_play.setOnClickListener(this);
bt_replay.setOnClickListener(this);
bt_stop.setOnClickListener(this);
sv.getHolder().addCallback(new Callback() {
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
System.out.println("holder被銷毀了");
if (mediaPlayer != null && mediaPlayer.isPlaying()) {
currentPosition = mediaPlayer.getCurrentPosition();
stop();
}
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
System.out.println("holder被創建了");
if (currentPosition > 0) {
play(currentPosition);
}
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format,
int width, int height) {
System.out.println("holder的大小變化了");
}
});
}
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.bt_play:
play(0);
break;
case R.id.bt_replay:
replay();
break;
case R.id.bt_stop:
stop();
break;
case R.id.bt_pause:
pause();
break;
default:
break;
}
}
/**
* 暫停音樂
*/
private void pause() {
if ("繼續".equals(bt_pause.getText().toString().trim())) {
mediaPlayer.start();
bt_pause.setText("暫停");
return;
}
if (mediaPlayer != null && mediaPlayer.isPlaying()) {
mediaPlayer.pause();
bt_pause.setText("繼續");
return;
}
}
/**
* 重新播放
*/
private void replay() {
if (mediaPlayer != null && mediaPlayer.isPlaying()) {
mediaPlayer.seekTo(0);
return;
}
play(0);
}
/**
* 停止播放音樂
*/
private void stop() {
if (mediaPlayer != null && mediaPlayer.isPlaying()) {
mediaPlayer.stop();
mediaPlayer.release(); // 記得釋放資源
mediaPlayer = null;
bt_play.setEnabled(true);
isplaying = false;
}
}
/**
* 播放音樂
*/
private void play(final int currentPosition) {
String path = et_path.getText().toString().trim();
try {
mediaPlayer = new MediaPlayer();
mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
/* 設置Video影片以SurfaceHolder播放 */
mediaPlayer.setDisplay(sv.getHolder());
mediaPlayer.setDataSource(path);
mediaPlayer.prepare(); // might take long! (for buffering, etc)
//mediaPlayer.prepareAsync();
mediaPlayer.setOnPreparedListener(new OnPreparedListener() {
@Override
public void onPrepared(MediaPlayer mp) {
mediaPlayer.start();
int max = mediaPlayer.getDuration();
sb.setMax(max);
mediaPlayer.seekTo(currentPosition);
new Thread() {
public void run() {
isplaying = true;
while (isplaying) {
int position = mediaPlayer.getCurrentPosition();
sb.setProgress(position);
try {
Thread.sleep(500);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
};
}.start();
}
});
mediaPlayer.setOnCompletionListener(new OnCompletionListener() {
@Override
public void onCompletion(MediaPlayer mp) {
bt_play.setEnabled(true);
}
});
bt_play.setEnabled(false);
} catch (Exception e) {
Toast.makeText(this, "播放失敗", 0).show();
e.printStackTrace();
}
}
}
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