remove the background of static text

[Cooker]

As showing in attached picture, I want to remove the background of static text ("Quality : 100" and "Resoultion...").
The program I write is following:

// Print Prompt Text
         hwndStaticTextQuality = CreateWindowEx(0L, "STATIC", NULL, WS_CHILD | WS_VISIBLE | ES_LEFT , 
		      FrameX+5, FrameY, 80, 15, hwnd, (HMENU) ID_STATIC_LABEL_QUALITY, GetModuleHandle(NULL), 0 );
         sprintf(prompt_text,"Quality:%d",QUALITY_DEFAULT);
         SetWindowText(hwndStaticTextQuality, prompt_text);

         hwndStaticTextSpatial = CreateWindowEx(0L, "STATIC", NULL, WS_CHILD | WS_VISIBLE | ES_LEFT , 
		      FrameX+5, FrameY+36, 100, 15, hwnd, (HMENU) ID_STATIC_LABEL_SPATIAL, GetModuleHandle(NULL), 0 );

         sprintf(prompt_text,"Resolution:1/%d",SPATIAL_DEFAULT);
         SetWindowText(hwndStaticTextSpatial, prompt_text);

What should I modify?
Thank you.

[Xatrix]

Does:
HDC hdc = GetDC(hwnd);
SetBkMode(hdc,TRANSPARENT);
work?

Just posting it because that's what I'm using when I output text using TextOut for example...

[HoM]

Did you check

www.codeguru.com

on that? Looking in C++ -> Controls -> Static you will find exactly what you have asked for.

eg.
http://www.codeguru.com/cpp/controls...cle.php/c8829/

[humptydumpty]

Simply use WM_CTLCOLORSTATIC to change background color of a static Control

[ovidiucucu]

Just you have to handle WM_CTLCOLORSTATIC message which is sent to parent window when the static control is to be redrawn. Inside the handler function, set backround mode TRANSPARENT and return a NULL (HOLLOW) brush.
Here is a brief example for all static controls from a dialog.
You can adapt it to your needs.

#include <WINDOWSX.H>
// ...
HBRUSH Dlg_OnCtlColor(HWND hwnd, HDC hdc, HWND hwndChild, int type);
// ...
// dialog procedure
BOOL CALLBACK DialogProc(HWND hwndDlg, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
   BOOL bRet = TRUE; // handled
   switch(uMsg)
   {
// ...
   case WM_CTLCOLORSTATIC:
      // //  NOTE: HANDLE_WM_CTLCOLORSTATIC is defined in <WINDOWSX.H>
      bRet = HANDLE_WM_CTLCOLORSTATIC(hwndDlg, wParam, lParam, Dlg_OnCtlColor);
      break;
// ...
   }
   return bRet;
}
// WM_CTLCOLORSTATIC message handler
HBRUSH Dlg_OnCtlColor(HWND hwnd, HDC hdc, HWND hwndChild, int type)
{
   SetBkMode(hdc, TRANSPARENT);
   return (HBRUSH)GetStockObject(HOLLOW_BRUSH);
}

Note: WM_CTLCOLORSTATIC is also sent for read-only or disabled edit controls.

[Cooker]

Just you have to handle WM_CTLCOLORSTATIC message which is sent to parent window when the static control is to be redrawn. Inside the handler function, set backround mode TRANSPARENT and return a NULL (HOLLOW) brush.
Here is a brief example for all static controls from a dialog.
You can adapt it to your needs.

#include <WINDOWSX.H>
// ...
HBRUSH Dlg_OnCtlColor(HWND hwnd, HDC hdc, HWND hwndChild, int type);
// ...
// dialog procedure
BOOL CALLBACK DialogProc(HWND hwndDlg, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
   BOOL bRet = TRUE; // handled
   switch(uMsg)
   {
// ...
   case WM_CTLCOLORSTATIC:
      // //  NOTE: HANDLE_WM_CTLCOLORSTATIC is defined in <WINDOWSX.H>
      bRet = HANDLE_WM_CTLCOLORSTATIC(hwndDlg, wParam, lParam, Dlg_OnCtlColor);
      break;
// ...
   }
   return bRet;
}
// WM_CTLCOLORSTATIC message handler
HBRUSH Dlg_OnCtlColor(HWND hwnd, HDC hdc, HWND hwndChild, int type)
{
   SetBkMode(hdc, TRANSPARENT);
   return (HBRUSH)GetStockObject(HOLLOW_BRUSH);
}

Note: WM_CTLCOLORSTATIC is also sent for read-only or disabled edit controls.

I add the following code:

 case WM_CTLCOLORSTATIC:
         hdc = GetDC(hwnd);
         SetBkMode(hdc, TRANSPARENT);
         GetStockObject(NULL_BRUSH);
         ReleaseDC(hwnd,hdc);
         break;

  case WM_SIZE:
      ...

But the result as attached picture.

[golanshahar]

try that:

wParam
Handle to the device context for the static control window.

case WM_CTLCOLORSTATIC:  
         SetBkMode((HDC)wParam, TRANSPARENT);
         return GetStockObject(NULL_BRUSH);
break;

Cheers

[ovidiucucu]

Just an aside note:
I used in my example a message cracker macro (defined in WINDOWSX.H) with the corresponding message handler function, in order to make the code easier to read/understand/develop/maintain.
Imagine a window procedure handling tens of messages with all stuff inside it. It becomes huge and can make the programmer's life a mess.

Returning to the subject:
As golanshahar already showed in his example, and also I said (maybe not enough underlined) you have to return a valid brush handle to be used by the system for painting the background of the control (in our case a null brush also known as hollow brush).

EDIT:
See this EXCELLENT ARTICLE.

[FireJocker]

This code works :

HBRUSH CDigiDialog::OnCtlColor(CDC* pDC, CWnd* pWnd, UINT nCtlColor)
{
	HBRUSH hbr;

	if ( nCtlColor == CTLCOLOR_STATIC ) 
	{
		pDC->SetBkMode(TRANSPARENT);
		hbr = (HBRUSH)GetStockObject( NULL_BRUSH );
	}

	else
	{
		hbr = CDialog::OnCtlColor(pDC, pWnd, nCtlColor);
	}
	
	return hbr;
}

[Cooker]

I get the error message:
error C2440: 'return' : cannot convert from 'void *' to 'long'
Why?

try that:

case WM_CTLCOLORSTATIC:  
         SetBkMode((HDC)wParam, TRANSPARENT);
         return GetStockObject(NULL_BRUSH);
break;

Cheers

[Cooker]

Like this?
case WM_CTLCOLORSTATIC:
HBRUSH hbr;
SetBkMode((HDC)wParam, TRANSPARENT);
hbr = (HBRUSH)GetStockObject(NULL_BRUSH);
break;
But the problem still exists!

This code works :

HBRUSH CDigiDialog::OnCtlColor(CDC* pDC, CWnd* pWnd, UINT nCtlColor)
{
	HBRUSH hbr;

	if ( nCtlColor == CTLCOLOR_STATIC ) 
	{
		pDC->SetBkMode(TRANSPARENT);
		hbr = (HBRUSH)GetStockObject( NULL_BRUSH );
	}

	else
	{
		hbr = CDialog::OnCtlColor(pDC, pWnd, nCtlColor);
	}
	
	return hbr;
}

[golanshahar]

I get the error message:
error C2440: 'return' : cannot convert from 'void *' to 'long'
Why?

I saw that you are using MFC so try this out:

HBRUSH CMyDlg::OnCtlColor(CDC* pDC, CWnd* pWnd, UINT nCtlColor) 
{
  HBRUSH hbr = CDialog::OnCtlColor(pDC, pWnd, nCtlColor);
  
  if ( pWnd->GetDlgCtrlID() == IDC_STATIC2 /*Id of the static control you want to change*/)
  {

    pDC->SetBkMode(TRANSPARENT);
    return (HBRUSH)::GetStockObject(HOLLOW_BRUSH);
  }
  return hbr;
}

Just make sure you are adding the OnCtlColor(..) with wizard.

Cheers

[FireJocker]

Code I gave you will remove the background of all your static text,

If you want to remove only some of them, use code like golanshahar wrote :

HBRUSH CDigiDialog::OnCtlColor(CDC* pDC, CWnd* pWnd, UINT nCtlColor)
{
	HBRUSH hbr;

	if ( ( pWnd->GetDlgCtrlID() == IDC_STATIC1 ) 
           ||( pWnd->GetDlgCtrlID() == IDC_STATIC2 ) ) // etc...
	{
		pDC->SetBkMode(TRANSPARENT);
		hbr = (HBRUSH)GetStockObject( NULL_BRUSH );
	}

	else
	{
		hbr = CDialog::OnCtlColor(pDC, pWnd, nCtlColor);
	}
	
	return hbr;
}