AsyncTask的onPostExecute不会被调用 [英] AsyncTask onPostExecute never gets called

问题描述

我不知道我做错了，但onPostExecute不会被调用。

I am not sure what I am doing wrong but onPostExecute never gets called.

• 在创建了一个名为BaseActivity.java一个基类
• 从我原来的活动我扩展这个类。
• 在里面BaseActivity放置PostToOpenFeint类

• 从UI线程的主要活动称之为我做的：

• Created a base class called BaseActivity.java
• From my original Activity I extended this class.
• Placed PostToOpenFeint class inside BaseActivity

• Called it from the UI thread from the main activity my doing:

new PostToOpenFeint.execute();

上的preExecute（），doInBackground（..）被触发，但由于某些原因，onPostExecute不会被调用。

The onPreExecute(), doInBackground(..) gets triggered, but for some reason the onPostExecute never gets called.

感谢你在前进！

戴夫

 private class PostToOpenFeint extends AsyncTask<Void, Void, Void> {
  /*
   * (non-Javadoc)
   * 
   * @see android.os.AsyncTask#doInBackground(Params[])
   */
  @Override
  protected Void doInBackground(Void... params) {
   // does all the work here
   return null;
  }


  /*
   * (non-Javadoc)
   * 
   * @see android.os.AsyncTask#onPostExecute(java.lang.Object)
   */
  @Override
  protected void onPostExecute(Void result) {
   // TODO Auto-generated method stub
   super.onPostExecute(result);
   Toast.makeText(MainScreen.this, "Done syncing", Toast.LENGTH_LONG).show();
  }

  /*
   * (non-Javadoc)
   * 
   * @see android.os.AsyncTask#onPreExecute()
   */
  @Override
  protected void onPreExecute() {
   // TODO Auto-generated method stub
   super.onPreExecute();
   Toast.makeText(MainScreen.this, "About to sync all your scores", Toast.LENGTH_LONG).show();
  }

---

寻找到它多了，这是我能够观察到。例如，如果我把这个电话：

---

Looking into it more, this is what I was able to observe. For example if I place this call:

 new PostToOpenFeint.execute();

右边的活性的onCreate后，然后一切工作正常。如果我把这个电话说，一个按钮监听器里。

right after onCreate of the Activity, then everything works fine. If I place this call say inside a button listener.

settingsButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
   new PostToOpenFeint.execute();
}
});

在onPostExecute（）不会被调用，不知道我做错了。我读的限制是从UI线程调用此，我从UI线程调用它。

The onPostExecute() never gets called, not sure what I am doing wrong. The restriction I read was to call this from UI Thread and I am calling it from UI thread.

推荐答案

我有一个类似的问题刚才。我被延长的AsyncTask＆LT;整数，整数，整数GT; 和我onPostExecute方法看起来像：

I had a similiar problem just now. I was extending AsyncTask<Integer,Integer,Integer> and my onPostExecute method looked like:

protected void onPostExecute(int result)

这似乎确定了我，但话又说回来，我更多的是.NET的家伙不是一个Java的家伙。 我把它改为：

This seemed OK to me, but then again I'm more of a .NET guy than a Java guy. I changed it to:

protected void onPostExecute(Integer result)

因为某种原因的Java认为有间 INT 的差异和整数？

我觉得你的问题是，你声明的返回类型为无效在

I think that your problem is that you're declaring the return type as void in your:

extends<Void,Void,Void>

这意味着没有参数，可以没有任何进展，也没有结果。如果你想要执行的东西，当它这样做，我认为你需要给它某种价值像和整数或布尔值。

That means no params, no progress and no result. If you want to execute something when it's done, I think you need to give it some kind of value like and integer or a boolean.

如果您更改扩展到：

<Void,Void,Integer>

现在你的传球没有参数，可以不发布任何进展，但返回的值。改变你的 onPostExecute 的方法来接受整数：

Now your passing no params, not publishing any progress, but are returning a value. Change your onPostExecute method to accept an Integer:

protected void onPostExecute(Integer result)

则返回在 doInBackground 方法更改为类似：

return 1;

那么就应该为您执行。

Then it should execute for you.

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