Asynctask 和 onclicklistener android 2.3.3 与 3.2

Question

在我的 Nexus One (android 2.3.3) 上，以下程序的行为与我的 xoom (android 3.2) 不同：

public class TestOnclickWithAsyncTask extends Activity {

private int mClicked = 0;

private final static String TAG = "TestOnclickWithAsyncTask";

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState); 

    setContentView(R.layout.main);
    RelativeLayout relativeLayout= (RelativeLayout) findViewById(R.id.img_control_panel);

    final Button button = new Button(this);

    button.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
            mClicked++;
            Log.i (TAG, "Clicked "+ mClicked + " times");
        }
    });

    relativeLayout.addView(button);


    new LongTask().execute();

}

private class LongTask extends AsyncTask<Void , Void, Void> {
    private ProgressDialog dialog;

      protected void onPreExecute() {
      dialog = new  ProgressDialog(TestOnclickWithAsyncTask.this);
      dialog.setMessage("Waiting ");
      dialog.setIndeterminate(true); 
      dialog.setCancelable(true); 
      try {
          dialog.show();
      } catch (Exception e){}
      }

        protected Void doInBackground(Void... notused) {
                try {
                    Thread.sleep (30000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }//do long task
            return null;
        }


        protected void onPostExecute(Void unusedg) { 
            dialog.dismiss();
            Log.i (TAG,"Long task finished");
        }

}

}

在我的 Nexus 上，我无法在 asynctask 运行时按下按钮（所需的行为）：

09-26 00:45:34.361: INFO/TestOnclickWithAsyncTask(3803): Long task finished
09-26 00:45:36.463: INFO/TestOnclickWithAsyncTask(3803): Clicked 1 times
09-26 00:45:36.814: INFO/TestOnclickWithAsyncTask(3803): Clicked 2 times
09-26 00:45:37.975: INFO/TestOnclickWithAsyncTask(3803): Clicked 3 times
09-26 00:45:38.435: INFO/TestOnclickWithAsyncTask(3803): Clicked 4 times

在我的 xoom 上，我只需按按钮和进度指示器消失。

09-26 00:49:05.440: INFO/TestOnclickWithAsyncTask(5887): Clicked 1 times
09-26 00:49:06.230: INFO/TestOnclickWithAsyncTask(5887): Clicked 2 times
09-26 00:49:06.580: INFO/TestOnclickWithAsyncTask(5887): Clicked 3 times
09-26 00:49:06.840: INFO/TestOnclickWithAsyncTask(5887): Clicked 4 times
09-26 00:49:08.170: INFO/TestOnclickWithAsyncTask(5887): Clicked 5 times
09-26 00:49:08.560: INFO/TestOnclickWithAsyncTask(5887): Clicked 6 times
09-26 00:49:30.960: INFO/TestOnclickWithAsyncTask(5887): Long task finished 
09-26 00:49:32.800: INFO/TestOnclickWithAsyncTask(5887): Clicked 7 times
09-26 00:49:33.810: INFO/TestOnclickWithAsyncTask(5887): Clicked 8 times

为什么会有所不同？更重要的是，如何防止 xoom 取消进度对话框？

Answer 1

当您不希望这样时，为什么还要调用 setCancelable(true) 呢？也许这会解决您的问题...

只是一个提示：

try {
    dialog.show();
} catch (Exception e) {

}

1. 您为什么要这样做？
2. 将代码包含在 try ... catch 中，并使用一般异常捕获而不做出任何反应，这是一个非常糟糕的习惯。当您这样做时，您应该始终留下评论并给出充分的理由。