asynctask取消onpostexecute

Question

我尝试并在"doInBackground"中捕获,如果应用程序在"doInBackground"中执行catch方法,我不会在代码中运行onPostExecute.代码如下:

public class DownloadFileAsync extends AsyncTask<String, Integer, Void> {
        @Override
        protected void onPreExecute(){
             super.onPreExecute();
     }

    @Override
    protected Void doInBackground(String... aurl) {
        try{
           //some code, jump to onPostexecute after complete
        }
        catch{
            //some code, don't do onPostExecute after complete
        }
        return null;

        }

    @Override
    protected void onProgressUpdate(Integer... progress) {          
    //some code
    }

    @Override
    protected void onPostExecute(Void unused) {
    //some code
    }
}

Answer 1

您可以尝试使用cancel(true)在doInBackground().请尝试以下代码:

protected Void doInBackground(String... aurl) {
    try{
       //some code, jump to onPostexecute after complete
    }
    catch{
        cancel(true);
    }
    return null;

    }

官方说明 cancel()

调用此方法将导致在doInBackground(Object [])返回后在UI线程上调用onCancelled(Object).调用此方法可确保永远不会调用onPostExecute(Object).调用此方法后,应定期从doInBackground(Object [])检查isCancelled()返回的值,以尽早完成任务.

查看此链接了解更多详情:

http://developer.android.com/reference/android/os/AsyncTask.html#cancel(boolean)