Visual C++ and MFC Programming 2nd Edition

Chapter 12: Dialog-Based Windows Visual C++ and MFC Fundamentals

COLOR_ACTIVEBORDER,COLOR_ACTIVECAPTION,

COLOR_APPWORKSPACE, COLOR_BACKGROUND, COLOR_BTNFACE,

COLOR_BTNSHADOW, COLOR_BTNTEXT, COLOR_CAPTIONTEXT,

COLOR_GRAYTEXT, COLOR_HIGHLIGHT, COLOR_HIGHLIGHTTEXT,

COLOR_INACTIVEBORDER, COLOR_INACTIVECAPTION, COLOR_MENU,

COLOR_MENUTEXT, COLOR_SCROLLBAR, COLOR_WINDOW,

COLOR_WINDOWFRAME, and COLOR_WINDOWTEXT.

To use one of these colors, cast it to HBRUSH and add 1 to its constant to paint the

background of your window:

CMainFrame::CMainFrame()

{

// Declare a window class variable

WNDCLASS WndCls;

const char *StrWndName = "Windows Fundamentals";

WndCls.style = CS_VREDRAW | CS_HREDRAW;

WndCls.lpfnWndProc = AfxWndProc;

WndCls.cbClsExtra = 0;

WndCls.cbWndExtra = 0;

WndCls.hInstance = AfxGetInstanceHandle();

WndCls.hIcon = AfxGetApp()->LoadStandardIcon(IDI_WARNING);

WndCls.hCursor = AfxGetApp()->LoadStandardCursor(IDC_CROSS);

WndCls.hbrBackground = (HBRUSH)(COLOR_ACTIVECAPTION+1);

WndCls.hCursor = AfxGetApp()->LoadStandardCursor(IDC_CROSS);

}

To get the value of a system color, call the GetSysColor() function. Its syntax is:

DWORD GetSysColor(int nIndex);

The nIndex argument should be a valid name of one of the system color constants such as

COLOR_ACTIVECAPTION. When this function has executed, it returns the

COLORREF value of the nIndex color. If you provide a wrong or unrecognized value as

the nIndex argument, this function returns 0, which is also a color and can therefore

produce an unexpected result. If you want to consider only existing valid colors, call the

GetSysColorBrush() function instead. Its syntax is:

HBRUSH GetSysColorBrush( int nIndex);

This function returns the color value of the system color that is passed as nIndex. If the

value of nIndex is not valid, the function returns NULL, which is not 0 and therefore is

not a color, producing a more predictable result.

Practical Learning: Building a Window Class

1. Change the contents of the file as follows:

#include <windows.h>

//---------------------------------------------------------------------------

LRESULT CALLBACK WndProc(HWND hWnd, UINT Msg,

WPARAM wParam, LPARAM lParam);

//---------------------------------------------------------------------------

INT WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,