android - onPostExecute on cancelled AsyncTask

Question

Does onPostExecute execute if the AsyncTask has been cancelled?

If it does execute, is it safe to say that I should always ask if the task has been cancelled (isCancelled) at the start of onPostExecute, before doing anything else?

Answer 1

The documented behaviour of onPostExecute on cancel() was changed between Android 2 and Android 4.

Android 2.3.7 onPostExecute :

Runs on the UI thread after doInBackground. The specified result is the value returned by doInBackground or null if the task was cancelled or an exception occured.

Android 4.0.1 onPostExecute :

Runs on the UI thread after doInBackground. The specified result is the value returned by doInBackground. This method won't be invoked if the task was cancelled.

So if you are still targeting Android 2 devices you should assume that onPostExecute will be called and in onPostExecute check for null result.