Android“只有创建视图层次结构的原始线程才能触摸其视图。”

问题：

I've built a simple music player in Android. 我已经在Android中构建了一个简单的音乐播放器。 The view for each song contains a SeekBar, implemented like this: 每首歌曲的视图都包含一个SeekBar，实现如下：

public class Song extends Activity implements OnClickListener,Runnable {
    private SeekBar progress;
    private MediaPlayer mp;

    // ...

    private ServiceConnection onService = new ServiceConnection() {
          public void onServiceConnected(ComponentName className,
            IBinder rawBinder) {
              appService = ((MPService.LocalBinder)rawBinder).getService(); // service that handles the MediaPlayer
              progress.setVisibility(SeekBar.VISIBLE);
              progress.setProgress(0);
              mp = appService.getMP();
              appService.playSong(title);
              progress.setMax(mp.getDuration());
              new Thread(Song.this).start();
          }
          public void onServiceDisconnected(ComponentName classname) {
              appService = null;
          }
    };

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.song);

        // ...

        progress = (SeekBar) findViewById(R.id.progress);

        // ...
    }

    public void run() {
    int pos = 0;
    int total = mp.getDuration();
    while (mp != null && pos<total) {
        try {
            Thread.sleep(1000);
            pos = appService.getSongPosition();
        } catch (InterruptedException e) {
            return;
        } catch (Exception e) {
            return;
        }
        progress.setProgress(pos);
    }
}

This works fine. 这很好。 Now I want a timer counting the seconds/minutes of the progress of the song. 现在，我需要一个计时器来计算歌曲进度的秒/分钟。 So I put a TextView in the layout, get it with findViewById() in onCreate() , and put this in run() after progress.setProgress(pos) : 所以我将TextView放在布局中，在onCreate()使用findViewById()进行获取，然后将其放在progress.setProgress(pos)之后的run() progress.setProgress(pos) ：

String time = String.format("%d:%d",
            TimeUnit.MILLISECONDS.toMinutes(pos),
            TimeUnit.MILLISECONDS.toSeconds(pos),
            TimeUnit.MINUTES.toSeconds(TimeUnit.MILLISECONDS.toMinutes(
                    pos))
            );
currentTime.setText(time);  // currentTime = (TextView) findViewById(R.id.current_time);

But that last line gives me the exception: 但是最后一行给我一个例外：

android.view.ViewRoot$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views. android.view.ViewRoot $ CalledFromWrongThreadException：只有创建视图层次结构的原始线程才能触摸其视图。

Yet I'm doing basically the same thing here as I'm doing with the SeekBar - creating the view in onCreate , then touching it in run() - and it doesn't give me this complaint. 但是，我在这里执行的操作基本上与在SeekBar执行的操作相同-在onCreate创建视图，然后在run()对其进行触摸-但这并没有给我这种抱怨。

---

解决方案：

参考一： https://stackoom.com/question/LerH/Android-只有创建视图层次结构的原始线程才能触摸其视图
参考二： https://oldbug.net/q/LerH/Android-Only-the-original-thread-that-created-a-view-hierarchy-can-touch-its-views

来源：oschina

链接：https://my.oschina.net/u/3797416/blog/4319699