Android: Does an AlertDialog.show() start a new thread?

Question

Does an AlertDialog.show() start a new thread? I don't see any indication in the Android documentation that it does, and would like confirmation.

Specifically, I want to make sure that the OnDismiss() callback occurs on the UI thread.

score 2 · Accepted Answer · answered Sep 10 '11 at 14:18

Short: No, it doesn't create a new thread and yes it runs in the ui thread.

Long: It should be running in the ui thread since it modifies ui stuff but you can create it from another thread and you will end having an exception. If you have a second thread you should do all the AlertDialog calls from the ui thread using one of the different ways to communicating with the ui thread. For instance runOnUiThread

score 0 · Answer 2 · answered Sep 10 '11 at 14:17

No. The AlertDialog is kicked off on the current Activity thread. Anything you want to do in the background would need to be done on a seperate thread ( Thread, AsyncTask, etc.). When dismissing the dialog, you indeed need to call the dismiss from the Activity thread.

score 0 · Answer 3 · answered Sep 10 '11 at 14:19

0

AFAIK it does not. There is no reason why it would. But to be sure you can inspect the source code.

answered Sep 10 '11 at 14:19

Peter Knego

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Android: Does an AlertDialog.show() start a new thread?

3 Answers3