Question

我想在另一个帖子中获取谷歌日历名称后更新微调器对象。当我执行它时，它会崩溃。我不确定是否需要使用不同的方法使其工作，或者是否存在问题。

private void updateGoogleCalendar() {
  try {
      Thread.sleep(4000);
      List<String> list = new ArrayList<String>();
      list.add("Sample Calendar");
      updatedCalendarNames = list.toArray(new String[0]);
      progressBar.dismiss();

    } catch (InterruptedException e) {
      e.printStackTrace();
    }
}
 public void initializeWidgets() {
    final Spinner spinner = (Spinner) layout.findViewById(R.id.googleCalendarSelection);
    final Button refreshCalendarBtn = (Button) layout.findViewById(R.id.refreshCalendarBtn);
    refreshCalendarBtn.setOnClickListener(new OnClickListener() {
       @Override
         public void onClick(View v) {
         progressBar = ProgressDialog.show(getContext(), "", "Loading...");
         new Thread(new Runnable() {

       @Override
         public void run() {
         updateGoogleCalendar();
         final ArrayAdapter<CharSequence> adapter = new ArrayAdapter<CharSequence>(getContext(), android.R.layout.simple_spinner_item);
         adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
         spinner.setAdapter(adapter);
         while (updatedCalendarNames == null) {
           try {
               Thread.sleep(500);

             } catch (InterruptedException e) {
               e.printStackTrace();
             }
        }
            for (String calendarName : updatedCalendarNames) {
            CharSequence charSequence = calendarName + "";
            adapter.add(charSequence);
          }                     
            }
         }).start();
       }
    });
  }

Answer 1

你没有说它崩溃或者如何崩溃，但我想这可能是因为你试图从非UI线程更新UI。请查看AsyncTask（请参阅here）了解相关信息。

Answer 2

您需要将您的ui更新代码添加到事件线程中，并且要通知UI /事件线程您需要实现Handler或AsyncTask，例如您可以通过处理程序更新如下：

public void initializeWidgets() {

    final Spinner spinner = (Spinner) layout.findViewById(R.id.googleCalendarSelection);


    final Button refreshCalendarBtn = (Button) layout.findViewById(R.id.refreshCalendarBtn);
    refreshCalendarBtn.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View v) {
            progressBar = ProgressDialog.show(getContext(), "", "Loading...");
            new Thread(new Runnable() {
                @Override
                public void run() {
                    updateGoogleCalendar();
                    final ArrayAdapter<CharSequence> adapter = new ArrayAdapter<CharSequence>(getContext(), android.R.layout.simple_spinner_item);
                    adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
                    spinner.setAdapter(adapter);

                    while (updatedCalendarNames == null) {
                        try {
                            Thread.sleep(500);
                        } catch (InterruptedException e) {
                            e.printStackTrace();
                        }
                    }
                    for (String calendarName : updatedCalendarNames) {
                        Message msg=handler.obtainMessage();
                        msg.obj = calendarName + "";
                        handler.sendMessage(msg);
                    }                       
                }
            }).start();
        }
    });

}


Handler handler=new Handler()
{
    public void handleMessage(Message msg)
    {
        String str=(String)msg.obj;
        adapter.add(charSequence);

    }
};

android - 更新进度条

2 个答案: