Transparent Text

I was wondering how do I output text that is transparent. I have a tab control and when I add a static control with text, the static control has the background color of a dialog box and the tab control has a different background color. I want the static control to have the same background color as the tab control so that text "blends" into the tab control. Any help is greatly appreciated.

style WS_EX_TRANSPARENT

Kuphryn

Either create the static control with the WS_EX_TRANSPARENT (see CreateWindowEx) extended window style or handle the static control parent's WM_CTLCOLORSTATIC message and return the handle of the brush used to paint the tab control.

WS_EX_TRANSPARENT gives me a black rectangle in the middle of a dialog box color rectangle in the middle of the tab control.

When I call WM_CTLCOLORSTATIC, no matter what I do afterward, all the colors change. The tab control color, the dialog box color, and the text color. It looks horrible. I think its because in the resource (.rc) file, I use DIALOGEX instead of DIALOG to create the dialog box. I think it attempts to convert the dialog box from a DIALOGEX to a DIALOG and fails.

>>When I call WM_CTLCOLORSTATIC<<

The message should be handled, not called. If you are handling the message, post your handling code.

Well, I use:

switch(Message) {
....
case WM_CTLCOLORSTATIC:
....
}

I think I just used the wrong word. Here is the code I use for WM_CTLCOLORSTATIC message:

Code:

....
case WM_CTLCOLORSTATIC:
     SetBkMode((HDC)wParam, TRANSPARENT);
     return true;
....

If I comment out the SetBkMode line, the same result is given where all the colors are "messed" up.

Ken Fitlike: "return the handle of the brush used to paint the tab control"

MSDN: "If an application processes this message, the return value is a handle to a brush that the system uses to paint the background of the static control."

Originally Posted by msdn WM_CTLCOLORSTATIC

If a dialog box procedure handles this message, it should cast the desired return value to a BOOL and return the value directly. If the dialog box procedure returns FALSE, then default message handling is performed.

The handler expects a brush type returned, if you want a NULL-brush, return GetStockObject(HOLLOW_BRUSH)

edit: biffed by Dante

Thanks for the information. Now I have:

Code:

...
case WM_CTLCOLORSTATIC:
     SetBkMode((HDC)wParam,TRANSPARENT);
     return (bool)GetStockObject(HOLLOW_BRUSH);
....

That gives me the same result if I comment out the entire WM_CTLCOLORSTATIC message handle where the background color of the static control is the same color as the dialog box control where I want it to be the same color of the tab control.

I change my code to:

Code:

...
case WM_CTLCOLORSTATIC:
     return (bool)SetBkMode(GetDlgItem(hWnd, ID_TEXT), TRANSPARENT);
...

That will give me the background color of a dialogex box background color instead of an ordinary dialog box background color. I know I'm close to solving this. Any more suggestions? Thanks for all your help so far.

bool and BOOL are different types - cast to BOOL, which I believe, is an unsigned int alias or better, INT_PTR as a DialogProc return type should be (you'll have to change declaration and definition of of your DialogProc to match).

If that doesn't work, try:

Code:

return (INT_PTR)GetClassLongPtr(hTabWnd, HGCL_HBRBACKGROUND);

where hTabWnd is your tab control handle.

Ah, thanks for your help. It is much appreciated. Changing from (bool) to (INT_PTR) worked. I sometimes overlook the simpliest things. I know my dialog proc function's return type is an INT_PTR and not a bool. Thanks again. Here is my final code:

Code:

case WM_CTLCOLORSTATIC:
     SetBkMode((HDC)wParam, TRANSPARENT);
     return (INT_PTR)GetStockObject(HOLLOW_BRUSH);

EDIT:

Woopsie...Forgot the SetBkMode line...