There is a way, but it won't be easy...
You can put a picture control (or a decoration) as top most object. Now,
there is your watermark! Problem is that this watermark will block all mouse
clicks, so everything behind it will be useless.
You'll have to catch mouse clicks on the picture control, and make the
controls behind it behave like they would if you'd clicked them directly.
This will be very difficult, unless you only have one or two boolean buttons
beneath it. For a numeric, you have to give it key focus when click in it,
but also calculate the text position of the cursor, increment and decrement
if that is where the user clicked, and don't forget about dragging the mouse
to select text!
Then you have the transparency problem... You can apply a mask to an image
in the picture control, but it is either on or off. So you have to make it
look transparent, by alpha blending everything behind the VI with the
picture... A hole new set of problems...
You might try to use GDI functions to draw a picture above the VI. In
general, this works poorly, since the objects disappear when LV updates it's
panel. But in this case, it could work. but if it doesn't, you're lost.
I'm not shy about hacking stuff like this, but in this case, I'll pass.
Perhaps if you explain more about your mmi, we could figure out another
clever scheme. For instance, a watermark over a graph area is a lot
easier...
Regards,
Wiebe.
