NPE & weak references when using toolbars

[Catalin Sanda]

Hello,

I have a problem with the toolbar buttons. I bind a command to a toolbar button and a menu entry, depending on certain events I enable or disable the command, enabling or disabling the corresponding components, but after a while I get a NullPointerException because the command manager uses weak references and the GC deallocates the buttons.

What am I doing wrong?

Tks
Catalin

[snpe]

Do You use TargetableActionCommand
If yes, then you have problem with ApplicationPage@fireFocusGained/FireFocusLost
It realocate TargetableActionCommand - try synchronize with this methods or extend DefaultApplicationPage and exclude this methods

regards

[Keith Donald]

Hmm... interesting. And these buttons are referenced by the containers containing them? If that's the case, I don't see how they could be garbage collected. We certainly need a JIRA issue for this if this indeed is happening consistently.

Keith

[oliverhutchison]

This is caused by some very whacky code in CommandFaceButtonManager ;-) I'm sitting on a patch but have not committed.

Though this NPE can only happen if the button GCd so I suspect something is throwing away and recreating the toolbar or menu in this case. I hit it when I was throwing away popup menus.

I'll commit the patch now.

Ollie

[Catalin Sanda]

I tested the patch, and it works.
tks a lot!

Catalin