我正在开发一个应用程序,它采用了自绘制标题栏,需要模仿系统默认标题栏。
那么我如何获取Windows中重叠窗口的默认标题栏高度呢?
那么我如何获取Windows中重叠窗口的默认标题栏高度呢?
从Firefox移植的源代码:
// mCaptionHeight is the default size of the NC area at
// the top of the window. If the window has a caption,
// the size is calculated as the sum of:
// SM_CYFRAME - The thickness of the sizing border
// around a resizable window
// SM_CXPADDEDBORDER - The amount of border padding
// for captioned windows
// SM_CYCAPTION - The height of the caption area
//
// If the window does not have a caption, mCaptionHeight will be equal to
// `GetSystemMetrics(SM_CYFRAME)`
int height = (GetSystemMetrics(SM_CYFRAME) + GetSystemMetrics(SM_CYCAPTION) +
GetSystemMetrics(SM_CXPADDEDBORDER));
return height;
注:高度取决于dpi。
一个解决方案是使用 AdjustWindowRectEx 函数,该函数还计算其他窗口边框的宽度,并允许窗口样式的变化:
RECT rcFrame = { 0 };
AdjustWindowRectEx(&rcFrame, WS_OVERLAPPEDWINDOW, FALSE, 0);
// abs(rcFrame.top) will contain the caption bar height
对于现代的 Windows(10+),有适用于 DPI 的版本:
// get DPI from somewhere, for example from the GetDpiForWindow function
const UINT dpi = GetDpiForWindow(myHwnd);
...
RECT rcFrame = { 0 };
AdjustWindowRectExForDpi(&rcFrame, WS_OVERLAPPEDWINDOW, FALSE, 0, dpi);
// abs(rcFrame.top) will contain the caption bar height
DPI/96.0f
进行乘法运算)。我得出了这个公式:std::ceil( ((GetSystemMetrics(SM_CYCAPTION) + GetSystemMetrics(SM_CYFRAME)) * dpi_scale) + GetSystemMetrics(SM_CXPADDEDBORDER) )
。 - melak47