Re: WS_EX_LAYERED but catching mouse messages
"David Ching" <dc@remove-this.dcsoft.com> wrote in message
news:Fnhvj.11905$Ej5.2159@newssvr29.news.prodigy.net...
Absolutely. Just create a window which doesn't paint anything directly
beneath your layered window. But since both this window and your layered
window are not child windows, you are responsible for making sure that the
second window stays directly beneath your layered window; when your
layered window moves or changes Z-order, so must the second window.
In the mouse click handler for the second window, just forward the mouse
click to your layered window.
On second thought, this won't work. Even though the second window doesn't
paint anything, it is still visible, so if the underlying windows change
their contents, the second window will block those new contents from being
visible.
In this case, I think your best bet to intercept mouse clicks in the
transparent areas is what Joe said: install a WH_MOUSE or WH_LL_MOUSE hook
that notifies you of mouse clicks.
One other possibility is to use the other type of WS_EX_LAYERED window which
offers per-pixel translucency, instead of using a color key to define
transparent areas. Then you could assign the transparent areas an
opaqueness of 1 instead of 0, so they are very faintly visible, but still
receive the mouse clicks. But the problem with using this type of layered
window is that it does not support child windows. If you have any WS_CHILD
windows of the layered window, this isn't an option.
-- David