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嗨\我的 Async onCreate 不断出现错误。这是代码和 logcat 跟踪。任何反馈表示赞赏。启动画面运行，然后应用程序在启动主屏幕后停止

public class HomeActivity extends ListActivity {
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2 回答 2

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doInBackground() runs on the background thread. So you cannot make changes to the ui on the background thread. You need to make changes or update ui on the ui thread.

http://developer.android.com/reference/android/os/AsyncTask.html

When an asynchronous task is executed, the task goes through 4 steps:

  1. onPreExecute(), invoked on the UI thread before the task is executed. This step is normally used to setup the task, for instance by showing a progress bar in the user interface.

  2. doInBackground(Params...), invoked on the background thread immediately after onPreExecute() finishes executing. This step is used to perform background computation that can take a long time. The parameters of the asynchronous task are passed to this step. The result of the computation must be returned by this step and will be passed back to the last step. This step can also use publishProgress(Progress...) to publish one or more units of progress. These values are published on the UI thread, in the onProgressUpdate(Progress...) step.

  3. onProgressUpdate(Progress...), invoked on the UI thread after a call to publishProgress(Progress...). The timing of the execution is undefined. This method is used to display any form of progress in the user interface while the background computation is still executing. For instance, it can be used to animate a progress bar or show logs in a text field.

  4. onPostExecute(Result), invoked on the UI thread after the background computation finishes. The result of the background computation is passed to this step as a parameter.

Use runonuithread or update ui in onPostExecute() depending on the result returned in doInbackground().

Check the link below

Doing UI task in doinbackground() in Android

于 2013-04-15T10:00:00.157 回答
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你不应该在你的doInBackgroundAsyncTask中操作视图。

于 2013-04-15T09:54:55.793 回答