MessageBox in worker thread

https://stackoverflow.com/questions/21943281

winapi
thread-safety
messagebox

14-10-2022
|

Question

I have an application which calls into plugin DLLs. Some of those calls are done from a worker thread (i.e. not the UI thread), and just might popup a dialog with MessageBox. According to this (http://www.codeproject.com/Articles/121226/MessageBoxes-and-worker-threads) the effective UI thread is switched to the thread calling MessageBox. This "crashes" the application since the message pump stops receiving messages. Any way to switch back the UI thread to the correct one ? Any work-around ?

Solution

The culprit was AttachThreadInput, see this message.

Licensed under: CC-BY-SA with attribution

Not affiliated with StackOverflow