我似乎不能改变一个SysDateTimePick32
控件的背景颜色(在这种情况下是白色):
在我的Win32 / MFC应用程序中。
我第一次尝试覆盖父窗口,甚至没有被调用的OnCtlColor
通知消息。
然后我尝试了这里描述的子类化方法,这被称为好,但控制没有改变视觉。 (我在Windows 8.1机器上进行了testing。)
那么有没有人有想法如何做到这一点?
PS。 我需要这个工作在Windows XP和以上。
我不确定下面的解决方案有多少黑客攻击,但似乎只是在有人提出一个更好的解决方案之前能够快速解决问题。 再次,它是基于此代码 ,并且还需要Windows Vista或更高版本的操作系统:
//Called from a subclassed WndProc case WM_PAINT: { PAINTSTRUCT ps; ::BeginPaint(hWnd, &ps); //Render control RenderWithBkgndColor(hWnd, ps.hdc, RGB(255, 0, 0)); ::EndPaint(hWnd, &ps); return 0; } void RenderWithBkgndColor(HWND hWnd, HDC hDC, COLORREF clrBkgnd) { //Render control with the background color //'clrBkgnd' = color for the background (if control is enabled) //SOURCE: // http://comp.os.ms-windows.programmer.win32.narkive.com/0H8cHhw1/setting-color-for-sysdatetimepick32-control RECT rect; ::GetWindowRect(hWnd, &rect); ::MapWindowPoints(NULL, hWnd, (LPPOINT)&rect, 2); long nWidth = rect.right - rect.left, nHeight = rect.bottom - rect.top; HDC hDCMem = ::CreateCompatibleDC(hDC); HBITMAP hBitmap = ::CreateBitmap(nWidth, nHeight, ::GetDeviceCaps(hDC, PLANES), ::GetDeviceCaps(hDC, BITSPIXEL), (const void *) NULL); if (hBitmap) { HBITMAP hBitmapOld = (HBITMAP)::SelectObject(hDCMem, hBitmap); //Render control itself ::SendMessage(hWnd, WM_PRINT, (WPARAM)hDCMem, PRF_CLIENT | PRF_CHILDREN | PRF_NONCLIENT); //Only if we have the color if(clrBkgnd != NULL) { //Only if control is enabled if((::GetWindowLongPtr(hWnd, GWL_STYLE) & (WS_VISIBLE | WS_DISABLED)) == (WS_VISIBLE | 0)) { #define ALLOWED_DIFF 20 DWORD dwBkgClr = ::GetSysColor(COLOR_WINDOW); //0xFFFFFF; DWORD br0 = dwBkgClr & 0xFF; DWORD br1 = (dwBkgClr & 0xFF00) >> 8; DWORD br2 = (dwBkgClr & 0xFF0000) >> (8 * 2); for(int y = 0; y < nHeight; y++) { for(int x = 0; x < nWidth; x++) { COLORREF clrPxl = ::GetPixel(hDCMem, x, y); DWORD r0 = clrPxl & 0xFF; DWORD r1 = (clrPxl & 0xFF00) >> 8; DWORD r2 = (clrPxl & 0xFF0000) >> (8 * 2); int nDiff_r0 = r0 - br0; int nDiff_r1 = r1 - br1; int nDiff_r2 = r2 - br2; if(abs(nDiff_r0) < ALLOWED_DIFF && abs(nDiff_r1) < ALLOWED_DIFF && abs(nDiff_r2) < ALLOWED_DIFF) { ::SetPixel(hDCMem, x, y, clrBkgnd); } } } } } ::BitBlt(hDC, rect.left, rect.top, nWidth, nHeight, hDCMem, 0, 0, SRCCOPY); ::SelectObject(hDCMem, hBitmapOld); ::DeleteObject(hBitmap); } ::DeleteDC(hDCMem); }