spurious BN_CLICKED messages

Posted on 1998-06-10
Last Modified: 2013-12-03
My application has a window which has several controls in it.  When I click on one of the buttons, I get two WM_COMMAND messages of type BN_CLICKED in response, one for press and one for release.  I return from the WindowProc call with a 0 to signify that the message was handled.  If I click on any of the other controls, I get the same message for the first control before I get one for the second control.  Are there any reasons this type of message could be triggered by anything other than a click on the right button?
Question by:pschwamb
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Expert Comment

ID: 1407492
Are you possibly setting capture to the button and forgetting to release it on the first button up message?

Expert Comment

ID: 1407493
BN_CLICKED is undistinguishable from WM_COMMAND created by, say, menu item. Are you posting/sending WM_COMMMAD messages to yourself?


Author Comment

ID: 1407494
Ok, I figured out that it's a problem with focus events. When I click on the button, a message gets sent to another program which pops up an error window (which takes focus away from the button) and sends a message back to the first program telling it to clear the button.  As soon as the first program's window is clicked on (anywhere) again, the button gets another focus event and another BN_CLICKED message, which triggers the error message again (yuck!).  My question should really be: what is a good way around this?
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Accepted Solution

tma050898 earned 100 total points
ID: 1407495
Is the message sent or posted? If it's sent, you can set a local static flag before the SendMessage. Then while your function is blocked on the SendMessage call, your function is reentered and the static flag can be checked. If the flag is on, you don't do anything. After the SendMessage returns, turn the flag back off.



Author Comment

ID: 1407496
The solution I came up with was to ignore every BN_CLICKED message after a focus event.

Expert Comment

ID: 1407497

I have no problem being graded poorly if I give out a poor effort and/or answer. However, why did you grade me with a 'D' when I took my time to help you? If I didn't answer your question, the proper way to have handled it would have been to reject my answer; NOT insult and embarass me with a 'D'!!!



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