AsyncTask and error handling on Android

Question

I\'m converting my code from using Handler to AsyncTask. The latter is great at what it does - asynchronous updates and handling of results in the

Answer 1

Another way that doesn't depend on variable member sharing is to use cancel.

This is from android docs:

public final boolean cancel (boolean mayInterruptIfRunning)

Attempts to cancel execution of this task. This attempt will fail if the task has already completed, already been cancelled, or could not be cancelled for some other reason. If successful, and this task has not started when cancel is called, this task should never run. If the task has already started, then the mayInterruptIfRunning parameter determines whether the thread executing this task should be interrupted in an attempt to stop the task.

Calling this method will result in onCancelled(Object) being invoked on the UI thread after doInBackground(Object[]) returns. Calling this method guarantees that onPostExecute(Object) is never invoked. After invoking this method, you should check the value returned by isCancelled() periodically from doInBackground(Object[]) to finish the task as early as possible.

So you can call cancel in catch statement and be sure that onPostExcute is never called, but instead onCancelled is invoked on UI thread. So you can show the error message.