我无法使Seekbar正常工作，第一首加载的歌曲不会让我使用SeekBar，但是当我加载第二首或第三首歌曲时，SeekBar会为他们工作。在加载歌曲Uri dataSource之后，我尝试初始化SeekBar，但是它仍然表现出相同的行为。
关于如何使SeekBar在第一首歌曲上运行的任何想法？
谢谢
...
public class MainActivity extends AppCompatActivity {
final int REQUEST_OPEN_FILE = 1;
MediaPlayer mediaPlayer = new MediaPlayer();
Uri audioFileUri;
/*SeekBar seekBar;*/
/*TextView SongProgress = findViewById(R.id.SongProgress);*/
@Override
protected void onCreate(Bundle savedInstanceState) {
...
}
...
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_OPEN_FILE) {
if (resultCode == RESULT_OK) {
audioFileUri = data.getData();
SeekBar seekBar;
seekBar = findViewById(R.id.seekbar);
seekBar.setMax(mediaPlayer.getDuration());
seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
seekBar.setProgress(progress);
mediaPlayer.seekTo(progress);
/*int Minutes=((progress/1000)/60);
int Seconds=((progress/1000)%60);
int time = Minutes + Seconds;
SongProgress.setText(time);*/
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
}
});
try {
if (mediaPlayer.isPlaying()) {
mediaPlayer.reset();
mediaPlayer.setDataSource(this, audioFileUri);
mediaPlayer.prepare();
mediaPlayer.start();
Toast.makeText(this, "Was Playing", Toast.LENGTH_SHORT);
}
else{
mediaPlayer.setDataSource(this, audioFileUri);
mediaPlayer.prepare();
mediaPlayer.start();
Toast.makeText(this, "Was not playing", Toast.LENGTH_SHORT);
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
...
...
}
答案 0 :(得分：0)
我能够解决自己的问题，在错误的位置初始化了seekBar更改侦听器。将其放在try catch块之后即可解决此问题。现在，我无法在播放歌曲时更新搜索栏。
SeekBar seekBar;
public class MainActivity extends AppCompatActivity implements Runnable {
....
@Override
protected void onCreate(Bundle savedInstanceState) {
...
seekBar = (SeekBar) findViewById(R.id.seekbar);
...
}
...
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_OPEN_FILE) {
if (resultCode == RESULT_OK) {
audioFileUri = data.getData();
try {
if (mediaPlayer.isPlaying()) {
mediaPlayer.reset();
mediaPlayer.setDataSource(this, audioFileUri);
mediaPlayer.prepare();
mediaPlayer.start();
seekBar.setMax(mediaPlayer.getDuration());
Toast.makeText(this, "Was Playing", Toast.LENGTH_SHORT);
} else {
mediaPlayer.setDataSource(this, audioFileUri);
mediaPlayer.prepare();
mediaPlayer.start();
seekBar.setMax(mediaPlayer.getDuration());
/*seekBar.getVisibility();
seekBar.setVisibility(View.INVISIBLE);*/
Toast.makeText(this, "Was not playing", Toast.LENGTH_SHORT);
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
seekBar.setProgress(progress);
mediaPlayer.seekTo(progress);
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
}
});
}
...
}
答案 1 :(得分：0)
好吧，我获得了搜索栏进度，以歌曲进行更新，以便搜索栏在播放时沿着音频文件跟踪。这是一个简单的带有处理程序的可运行程序，我已在此处的代码中发布了该处理程序。您必须有一个可运行的循环才能在播放歌曲时跟踪歌曲，以更新搜索栏。那么您必须编写一个处理程序来调用该可运行循环。要注意的一件事是，如果不将Boolean if（fromUser）布尔值添加到改变的监听器中，则线程将使它播放断断续续，因为它也正在更新与seekBar更新进度功能有关的进度。
SeekBar seekBar;
Handler handler = new Handler();
@Override
protected void onCreate(Bundle savedInstanceState) {
...
seekBar = (SeekBar) findViewById(R.id.seekbar);
...
}
...
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_OPEN_FILE) {
if (resultCode == RESULT_OK) {
audioFileUri = data.getData();
try {
if (mediaPlayer.isPlaying()) {
seekBar.setProgress(0);
mediaPlayer.reset();
mediaPlayer.setDataSource(this, audioFileUri);
mediaPlayer.prepare();
mediaPlayer.start();
seekBar.setMax(mediaPlayer.getDuration()); // Set the Maximum range of the
Toast.makeText(this, "Was Playing", Toast.LENGTH_SHORT);
} else {
seekBar.setProgress(0);
mediaPlayer.setDataSource(this, audioFileUri);
mediaPlayer.prepare();
mediaPlayer.start();
seekBar.setMax(mediaPlayer.getDuration()); // Set the Maximum range of the
/*seekBar.getVisibility();
seekBar.setVisibility(View.INVISIBLE);*/
Toast.makeText(this, "Was not playing", Toast.LENGTH_SHORT);
}
} catch (Exception e) {
e.printStackTrace();
}
int mediaPos = mediaPlayer.getCurrentPosition();
int mediaMax = mediaPlayer.getDuration();
seekBar.setMax(mediaMax); // Set the Maximum range of the
seekBar.setProgress(mediaPos);// set current progress to song's
handler.removeCallbacks(moveSeekBarThread);
handler.postDelayed(moveSeekBarThread, 1000);
}
}
seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
if(fromUser) {
seekBar.setProgress(progress);
mediaPlayer.seekTo(progress);
}
else{}
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
}
});
}
private Runnable moveSeekBarThread = new Runnable() {
public void run() {
if(mediaPlayer.isPlaying()){
int mediaPos_new = mediaPlayer.getCurrentPosition();
int mediaMax_new = mediaPlayer.getDuration();
seekBar.setMax(mediaMax_new);
seekBar.setProgress(mediaPos_new);
handler.postDelayed(this, 100); //Looping the thread after 0.1 second
// seconds
}else if(mediaPlayer.getCurrentPosition() == mediaPlayer.getDuration()){}
}
};