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I am getting an access violation when deleting a TsCheckBox.
I have a dynamically generated form with TsCheckBox and an “Apply” button that is the default.
If I click the Apply button then the form closes and the TsCheckBox is deleted without issue.
If I press enter the Apply button’s OnClick triggers and the form closes but the TsCheckBox throws an access violation in WndProc when handling WM_KILLFOCUS or CM_EXIT.Tracing it though I can see the TsCheckBok.Destroy is called and deletes fCommonData and then calls the inherited Destroy which in turn calls the WndProc which then tries to update the fCommonData.
Moving the FreeAndNil for fCommonData to after the inherited solves the problem.
P.S. Is there a reason why you have FImageChangeLink.Free rather than FreeAndNil(FImageChangeLink) in the Destroy?
Hello!
Is it possible to make a demo with such dialog and where the error is repeated?P.S. Is there a reason why you have FImageChangeLink.Free rather than FreeAndNil(FImageChangeLink) in the Destroy?
No reason. Do you think, FreeAndNil will be better there? Component is killed in any case there.
Skin is Material Dark and needs to be in C:\AlphaSkins\Skins
Run the app and press enter to get the exception.FreeAndNil is always better than Free – if you do end up using it later you can tell it is a nil pointer use rather than an arbitary address (or worse it works and corrupts some other object). It also means the exception is in the the deleted object not several levels down.
Thank you
Could you share source files also, please?
Can’t run Exe, unfortunately, many Bpl files are required there.I have attached a reworked exe and full project.
It should now need less bpls – hopefully only Berlin ones.To see the issue run the exe and select the checkbox, then press enter.
To see it work correctly click the apply button.
They both call PopulateEditor that destroys the TsCheckBox.
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