Running multiple Asyntasks simultaneously

Question

I have a problem that I cant understand it at all!. I have an Asynctask that connects to a web service and download some data.

But when I do this my other Asynctasks waits to this Asynctask to finish his work evenAsynctasksin otherActivities`!!. But I can't understand this.

How I can avoid this?. I was thinking that Asynctasks can run simultaneously but now it doesn't!. What is the problem? It seems REST and downloading stream data blocks the entire app.

You are going to have to show us some code. It is quite possible to run two or more async tasks simultaneously. — Dale Wilson, Sep 23 '13 at 18:55
http://developer.android.com/reference/android/os/AsyncTask.html - just read the documentation :) — 323go, Sep 23 '13 at 19:05

score 5 · Accepted Answer · edited Jun 20 '20 at 09:12

If you're running on Android 3.0 or later, and you're using the default implementation of AsyncTask (i.e. the one from the framework), it'll only execute a single task at a time. It is, however, possible to get parallel execution. See below.

From the documentation of AsyncTask

Order of execution

When first introduced, AsyncTasks were executed serially on a single background thread. Starting with DONUT, this was changed to a pool of threads allowing multiple tasks to operate in parallel. Starting with HONEYCOMB, tasks are executed on a single thread to avoid common application errors caused by parallel execution.

If you truly want parallel execution, you can invoke executeOnExecutor(java.util.concurrent.Executor, Object[]) with THREAD_POOL_EXECUTOR.

score 2 · Answer 2 · edited Feb 15 '16 at 18:41

2

Use a executoOnExecutor

TheTask task = new TheTask();
task.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, params);

http://developer.android.com/reference/java/util/concurrent/Executor.html

edited Feb 15 '16 at 18:41

Michell Bak

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answered Sep 23 '13 at 19:03

Raghunandan

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Running multiple Asyntasks simultaneously

2 Answers2