From 74d7dfad43fad104efbebdcac5e03625953cc035 Mon Sep 17 00:00:00 2001 From: Yuhang Zhao <2546789017@qq.com> Date: Wed, 29 Apr 2020 22:02:25 +0800 Subject: [PATCH] Fix flashing issue when maximizing. The window will flash when maximizing and restoring (the whole will become totally transparent at that moment, and after it has been maximized or restored, it will become not transparent again). Caused by passing negative values to DwmExtendFrameIntoClientArea. Fixes: #4 Signed-off-by: Yuhang Zhao <2546789017@qq.com> --- winnativeeventfilter.cpp | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-) diff --git a/winnativeeventfilter.cpp b/winnativeeventfilter.cpp index f6ef2c3..de49755 100644 --- a/winnativeeventfilter.cpp +++ b/winnativeeventfilter.cpp @@ -606,13 +606,7 @@ void UpdateFrameMarginsForWindow(HWND handle) { const DWMNCRENDERINGPOLICY ncrp = DWMNCRP_ENABLED; m_lpDwmSetWindowAttribute(handle, DWMWA_NCRENDERING_POLICY, &ncrp, sizeof(ncrp)); - // Negative margins have special meaning to - // DwmExtendFrameIntoClientArea. Negative margins create the "sheet - // of glass" effect, where the client area is rendered as a solid - // surface with no window border. Use positive margins have similar - // appearance, but the window background will be transparent, we - // don't want that. - margins = {-1, -1, -1, -1}; + margins = {0, 0, 1, 0}; } m_lpDwmExtendFrameIntoClientArea(handle, &margins); } @@ -643,6 +637,8 @@ void createUserData(HWND handle, userData->windowData = *data; } } else { + // Yes, this is a memory leak, but it doesn't hurt much, unless your + // application has thousands of windows. WinNativeEventFilter::WINDOW *_data = new WinNativeEventFilter::WINDOW; _data->hWnd = handle; @@ -827,9 +823,9 @@ bool WinNativeEventFilter::nativeEventFilter(const QByteArray &eventType, // 标题栏和窗口边框又会回来，这当然不是我们想要的结果。根据MSDN，当wParam // 为FALSE时，只能返回0，但当其为TRUE时，可以返回0，也可以返回一个WVR_常 // 量。根据Chromium的注释，当存在非客户区时，如果返回WVR_REDRAW会导致子 - // 窗口/子控件出现奇怪的bug（自绘控件错位），并且Lucas在Windows - // 10上成功复现，说明这个bug至今都没有解决。我查阅了大量资料，发现唯一的解 - // 决方案就是返回0。但如果不存在非客户区，且wParam为TRUE，最好返回 + // 窗口/子控件出现奇怪的bug（自绘控件错位），并且Lucas在Windows 10 + // 上成功复现，说明这个bug至今都没有解决。我查阅了大量资料，发现唯一的解决 + // 方案就是返回0。但如果不存在非客户区，且wParam为TRUE，最好返回 // WVR_REDRAW，否则窗口在调整大小可能会产生严重的闪烁现象。 // 虽然对大多数消息来说，返回0都代表让Windows忽略此消息，但实际上不同消息 // 能接受的返回值是不一样的，请注意自行查阅MSDN。