HOWTO: Change the Color of an Edit Control

• Microsoft Windows Software Development Kit (SDK) versions 3.0, 3.1

SUMMARY

The source code fragment below demonstrates how to paint the foreground and background of a single-line edit control in an application developed for the Microsoft Windows graphical environment. It creates a window that contains one single-line edit control and paints the edit control cyan on blue.

Windows sends the WM_CTLCOLOR message to the parent of an edit control before the control is painted. If desired, the parent window, usually a dialog box procedure, can process this message and change the text and background colors of the control.

NOTE: WM_CTRLCOLOR is obsolete on Windows NT and Windows 95. Instead, you would use WM_CTLCOLORBTN, WM_CTLCOLORDLG, WM_CTLCOLOREDIT, WM_CTLCOLORLISTBOX, WM_CTLCOLORMSGBOX, WM_CTLCOLORSCROLLBAR, or WM_CTLCOLORSTATIC.

MORE INFORMATION

The following MainWndProc demonstrates WM_CTLCOLOR processing:

  long FAR PASCAL MainWndProc(HWND hwnd, unsigned msg,
                               WORD wParam, LONG lParam)
   {
   static   HWND     hwndEdit;
   static   HBRUSH   hBrush;

      switch (msg)
      {
         case WM_CREATE:
            {
               HDC hdc;
               TEXTMETRIC tm;

               hdc = GetDC(hwnd);
               GetTextMetrics(hdc, &tm);
               ReleaseDC(hwnd, hdc);

               hwndEdit = CreateWindow("edit", NULL,
                               WS_CHILD | WS_VISIBLE
                               | ES_AUTOHSCROLL | ES_MULTILINE,
                               10, 20, 100, tm.tmHeight,
                               hwnd, 1, hInst, NULL);

               // Create a blue brush to be used for the edit control's
               // background color.
               hBrush = CreateSolidBrush(RGB(0, 0, 255));
            }
            break;

         case WM_CTLCOLOR:
         {
            // Set foreground and background colors only if this
            // is an edit control.
            if (HIWORD(lParam) == CTLCOLOR_EDIT)
            {
               // Set the edit control's foreground text color to
               // cyan and the text's background color to blue.
               SetTextColor(wParam, RGB(0, 255, 255));
               SetBkColor(wParam, RGB(0, 0, 255));

               // Properly originate the background brush. This is
               // of use if the brush is a pattern instead of a
               // solid color.
               UnrealizeObject(hBrush);
               SetBrushOrg(wParam, 0, 0);

               // Return a handle to the background brush for the edit
               // control.
               return (DWORD)hBrush;
            }
         }
         break;

         case WM_SETFOCUS:
            SetFocus(hwndEdit);
            return 0;

         case WM_DESTROY:
            PostQuitMessage(0);
            DeleteObject(hBrush);
            break;
      }
      return DefWindowProc(hwnd, msg, wParam, lParam);
   } 

Additional query words:

Keywords : kb16bitonly kbCtrl kbEditCtrl kbGrpUser
Version : WINDOWS:3.0,3.1
Platform : WINDOWS
Issue type : kbhowto