Изменить цвет окна - C++ WinAPI - Ответ 3852166

#include <windows.h>
 
static const char * g_cls           = "wb_cls32";
static HWND         g_wnd;
static HBRUSH       g_brush[2];
static int          g_brush_index   = 0;
 
LRESULT CALLBACK g_wnd_proc( HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam )
{
    switch ( uMsg ) {
        case WM_LBUTTONDOWN:
            g_brush_index ^= 1;
            InvalidateRect( hWnd, NULL, FALSE );
            return 0;
 
        case WM_PAINT:
            PAINTSTRUCT ps;
            BeginPaint( hWnd, &ps );
            FillRect( ps.hdc, &ps.rcPaint, g_brush[g_brush_index] );
            EndPaint( hWnd, &ps );
            return 0;
 
        case WM_DESTROY:
            PostQuitMessage( 0 );
            return 0;
    }
    return DefWindowProc( hWnd, uMsg, wParam, lParam );
}
 
int APIENTRY WinMain( HINSTANCE hInst, HINSTANCE hPInst, LPSTR lpCmdLine, int nCmdShow )
{
    g_brush[0] = (HBRUSH)GetStockObject( WHITE_BRUSH );
    g_brush[1] = (HBRUSH)GetStockObject( BLACK_BRUSH );
 
    WNDCLASS wc;
    ZeroMemory( &wc, sizeof( WNDCLASS ) );
    wc.lpfnWndProc      = g_wnd_proc;
    wc.hInstance        = hInst;
    wc.lpszClassName    = g_cls;
    wc.hCursor          = LoadCursor( NULL, IDC_ARROW );
    wc.hbrBackground    = g_brush[g_brush_index];
    RegisterClass( &wc );
 
    g_wnd = CreateWindow(
        g_cls, NULL, WS_OVERLAPPEDWINDOW | WS_VISIBLE,
        CW_USEDEFAULT, CW_USEDEFAULT,
        CW_USEDEFAULT, CW_USEDEFAULT,
        NULL, NULL, hInst, NULL );
 
    MSG msg;
    while ( GetMessage( &msg, NULL, 0, 0 ) ) {
        TranslateMessage( &msg );
        DispatchMessage( &msg );
    }
 
    return 0;
}