ProgressDialog没有显示出来，尽管显示（）被调用

Question

我有一个奇怪的问题，正在创建一个对话框，并呼吁“秀（）”，但不是在我的活动可见......

的东西是它通过调用“作秀”，我已经看到了它在调试器，但没有...

这里是代码：

protected void initializeSpinners() { 
    spnPlayLists = (Spinner) findViewById(R.id.spnLists); 
    spnProviders = (Spinner) findViewById(R.id.spnProvider); 
    spnProviders.setOnItemSelectedListener(new OnItemSelectedListener() { 

     @Override 
     public void onItemSelected(AdapterView<?> _spinner, View _parent, 
       int _pos, long _id) { 
      if (_spinner == spnProviders) { 
       String[] playListsId = core.getAllPlayListsFrom(_pos); 
       int items = playListsId.length; 
       **showProgressDialog(items);** 
       String[] playListsNames = new String[items]; 
       String[] playListsThumbs = new String[items]; 
       playLists = new PlayList[items]; 
       for (int i = 0; i < items; i++) { 
        String id = playListsId[i]; 
        PlayList playList = core.getPlayList(id, true); 
        playLists[i] = playList; 
        playListsNames[i] = playList.title; 
        playListsThumbs[i] = playList.thumb; 
        handle.sendEmptyMessage(i); 
       } 
       loadPlayLists(playListsNames, playListsThumbs); 
       myPd_bar.dismiss(); 
      } 
     } 

     @Override 
     public void onNothingSelected(AdapterView<?> _arg0) { 
     } 

    }); 

    ProvidersArrayAdapter providersAdapter = new ProvidersArrayAdapter(this); 
    spnProviders.setAdapter(providersAdapter); 
} 

和函数调用：

private void showProgressDialog(int _items) { 
    handle = new Handler() { 
     @Override 
     public void handleMessage(Message msg) { 
      super.handleMessage(msg); 
      myPd_bar.setProgress(msg.what + 1); 
     } 
    }; 

    myPd_bar = new ProgressDialog(Intro.this); 
    myPd_bar.setMessage("Loading...."); 
    myPd_bar.setTitle("Please Wait.."); 
    myPd_bar.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL); 
    myPd_bar.setProgress(0); 
    myPd_bar.setMax(_items); 
    **myPd_bar.show();** 
} 

我在做什么坏事？

Answer 1

最后我意识到了。我在微调控制器中持有活动线程，所以它不会显示任何内容，直到完成！

这里是我的解决方案，使用asyntask（正确的，我用的是他们糟糕的播放列表负载，并阻止）

protected void setupDialog() { 
    handle = new Handler() { 
     @Override 
     public void handleMessage(Message msg) { 
      super.handleMessage(msg); 
      if (msg.what < 0){ 
       loadPlayLists(playListsNames, playListsThumbs); 
       myPd_bar.dismiss(); 
      } else { 
       myPd_bar.setProgress(msg.what + 1); 
      } 
     } 
    }; 

    myPd_bar = new ProgressDialog(Intro.this); 
    myPd_bar.setMessage(WAIT_MESSAGE); 
    myPd_bar.setTitle(WAIT_TITLE); 
    myPd_bar.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL); 
    myPd_bar.setProgress(0); 
} 

protected void initializeSpinners() { 
    spnPlayLists = (Spinner) findViewById(R.id.spnLists); 
    spnProviders = (Spinner) findViewById(R.id.spnProvider); 
    spnProviders.setOnItemSelectedListener(new OnItemSelectedListener() { 

     @Override 
     public void onItemSelected(AdapterView<?> _spinner, View _parent, 
       int _pos, long _id) { 
      if (_spinner == spnProviders) { 
       String[] playListsId = core.getAllPlayListsFrom(_pos); 
       int items = playListsId.length; 
       myPd_bar.setMax(items); 
       myPd_bar.show(); 
       new AsyncTask<String[], Integer, Long>(){ 

        @Override 
        protected Long doInBackground(String[]... _playListsId) { 
         int items = _playListsId[0].length; 
         playListsNames = new String[items]; 
         playListsThumbs = new String[items]; 
         playLists = new PlayList[items]; 
         for (int i = 0; i < items; i++) { 
          String id = _playListsId[0][i]; 
          PlayList playList = core.getPlayList(id, true); 
          playLists[i] = playList; 
          playListsNames[i] = playList.title; 
          playListsThumbs[i] = playList.thumb; 
          publishProgress(i); 
         } 
         return null; 
        } 

        @Override 
        protected void onProgressUpdate(Integer... _progress) { 
         handle.sendEmptyMessage(_progress[0]); 
        } 

        @Override 
        protected void onPostExecute(Long _result) { 
         handle.sendEmptyMessage(-1); 
        } 
       }.execute(playListsId); 
      } 
     } 

     @Override 
     public void onNothingSelected(AdapterView<?> _arg0) { 
     } 

    }); 

    ProvidersArrayAdapter providersAdapter = new ProvidersArrayAdapter(this); 
    spnProviders.setAdapter(providersAdapter); 
} 

Answer 2

您的对话框出现之前可能会被解雇。基本上你的循环没有足够长的时间来显示视图。

你有没有试过评论退出行，看看它是否出现呢？