Mouse down not firing for left mouse button

2008-05-21 08:32:31 PM
I've got a problem that's puzzling me. I've an application that's been
working fine (MDI app). I've recently done quite a few changes (but mostly
not to the child MDI window).
All of a sudden my mouse down handler doesn't get called for the left mouse
button in the child window. Fine for right but not left.
I've tried tracing the assembler code in TControl.DoMouseDown but that
never gets called either for a left button mouse down.
I've ran my app on a different computer and the effect is the same. The
mouse down does fire on this form when a panel is clicked, it's just the
form body that isn't responding correctly.
I've obviously altered somethnig but what ? I've never come across this
I've tried removing the handler and reassigned but makes no difference. My
form is a subclass of another form type whichj in itself is a subclass of
TForm. The sub classes make no use of the mousedown event and are relativly
I've tested another form and it works fine for that so it's something I've
done on this particular form but I'm at a loss as to what I've done.
Anyone any ideas ?