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POReturn a value from AsyncTask in Android
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copied!<p>One simple question: is it possible to return a value in <code>AsyncTask</code>?</p> <pre><code>//AsyncTask is a member class private class MyTask extends AsyncTask<Void, Void, Void>{ protected Void doInBackground(Void... params) { //do stuff return null; } @Override protected void onPostExecute(Void result) { //do stuff //how to return a value to the calling method? } } </code></pre> <p>And then within my <code>Activity</code>/<code>Fragment</code>:</p> <pre><code>// The task is started from activity myTask.execute() // something like this? myvalue = myTask.getvalue() </code></pre> <p><strong>EDIT: This was asked a long time ago where I wasn't familiar with Java, now that I'm better with it, I 'll do a quick summary:</strong></p> <p>The point of async task is that the task is <code>asynchronous</code>, meaning that after you call <code>execute()</code> on the task, the task starts running on a thread of its own. returning a value from asynctask would be pointless because the original calling thread has already carried on doing other stuff (thus the task is asynchronous). </p> <p>Think of time: At one point of time, you started a task that will run in parallel with the main thread. When the parallel-running task completed, time has also elapsed on the main thread. The parallel task cannot go back in time to return a value to the main thread.</p> <p>I was coming from C so I didn't know much about this. But it seems that lots of people are having the same question so I thought I would clear it up a bit.</p>

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