Redraw titlebar after setting dark mode in Windows - c++

I am using the following library call to change the window to dark mode:
BOOL dark = TRUE;
DwmSetWindowAttribute(hwnd, DWMWA_USE_IMMERSIVE_DARK_MODE, &dark, sizeof(dark));
This works, with a small caveat. The title bar doesn't update until some additional event happens, like maximizing, losing focus, resizing, etc. (but not moving the window).
I have tried UpdateWindow and a huge number of combinations of flags on RedrawWindow with no luck. How can I force the title bar to redraw?
Edit I was able to force the reset by programmatically resizing the window, then resetting it to the previous size. But that seems like a terrible method. There must be a proper solution.

Related

CMFCMenuButton not properly repainting when toggling high contrast mode

In an C++ MFC project I'm using CMFCMenuButton using MSVC 2013.
When I toggle the high contrast mode the button is not properly repainted (for comparison a normal button is displayed):
Calling Invalidate() or ShowWindow(SW_HIDE);ShowWindow(SW_SHOW); seem to have no effect - even minimizing the dialog does not cause a proper redraw. How can I force the button to repaint with the updated system color?
Update: Forcing the colors after toggling contrast mode just makes the button text visible, however the button itself, the border, is not visible.
m_ctrlOkButton.SetFaceColor(::GetSysColor(COLOR_BTNFACE));
m_ctrlOkButton.SetTextColor(::GetSysColor(COLOR_BTNTEXT));
Took me a while, but I was able to solve this. I'm inheriting from the CMFCMenuButton class so that I can handle some events:
Get the color on the button right:Handle the WM_SYSCOLORCHANGE event and call GetGlobalData()->UpdateSysColors(); (make sure it's propagated to our parent before, e.g., by __super::OnSysColorChange();)
Get the border and background right:Handle the WM_THEMECHANGED event and call CMFCVisualManager::GetInstance()->DestroyInstance(); in order to close all opened theme data handles.

Avoid Flickering on a dialog that moves its controls on resize

I have a popup dialog( CDialog ) that handles WM_CTLCOLOR message to color itself. It is having some controls (like bitmap buttons) that draws themselves using OwnerDraw. It is also having a control that displays an image with size that takes up to 70% of the dialog.
When user re-sizes the dialog, some of the controls in the dialog should be re-positioned (not re-sized). It also involves re-sizing of the image inside the dialog. As the re-sizing of image makes the whole process slow, individual re-positioning of the controls are causing a visual effect of flickering.
I need to get rid of these. One idea is to put the controls as the children of an intermediate dialog that is the child of the original popup dialog. So, when there is a re-size, I can re-position the dialog only instead of moving each controls individually. (Re-position happens only in one direction (x or y), so moving the intermediate dialog should be enough.
As it involves some coding effort, before going this way, I need answers to the following questions:
Will this work?
If yes, whats the complexity involved in this method?
Is there a better way?
Please help!
Simple fixes are:
creating the slow window last so that it doesn't hold up drawing of the simple controls
turning on the WS_EX_COMPOSITED style flag so Windows double-buffers the entire window, including its children. Beware of painting artifacts
turning off the WS_CLIPCHILDREN style flag so the holes are not so noticeable. Making the background white would accomplish the same
keeping the drawing of slow controls simple between WM_ENTERSIZEMOVE and WM_EXITSIZEMOVE
using less controls, burning up an expensive window on a simple string or image is unnecessary
It will probably work, but you should try solutions that don't alter your control hierarchy before, because it has other subtle consequences (focus, tab order, message notifications, etc).
Try one or all of the following:
Use BeginDeferWindowPos/DeferWindowPos/EndDeferWindowPos functions to move the children.
Set the WS_CLIPCHILDREN style flag in the dialog.
Set the WS_EX_LAYERED extended style flag in the dialog.

effective Overlapping of dialog windows in Visual C++ 6

Hello there I have issue with overlapping of child windows,I have created a software with menu driven interface( IDR_MAINFRAME - CFormView
etc) and upon clicking one of the menu items another child-window appears( Dialog based ) where I do the calculations as a normal
calculator.Now if I open any other entry say conversion of metrics which is also in menu entry then on overlapping with any other such
window the background windows gets horribly disfigured and if i move about the calculator or the metrics conversion calculator randomly
they get disfigured and its a mess.Also I have put up a bitmap image on the background.Upon moving the calculator the background image also
gets erased.
Please let me know about how to handle this issue.I have googled and found that handling of paint messages or WM_ERASEBKGND helps ..but I
have tried this piece of code which just doesn't help in OnEraseBkGnd();
BOOL COfficesoftDlg::OnEraseBkgnd(CDC* pDC)
{
// TODO: Add your message handler code here and/or call default
CRect Rect;
GetClientRect(Rect);
//ClientToScreen(&Rect);
//this->ScreenToClient(&Rect);
this->InvalidateRect(Rect);
return CDialog::OnEraseBkgnd(pDC);
}
how can i achieve the smooth overlapping of different windows like a notepad overlapping a word document or even a calculator or even a VC6
IDE in my project.
Please explain it with an example .I am just a newbie and I need to understand in detail...thanks and regards
Override OnEraseBkgnd and return true so it stops erasing the background you're painting. Returning TRUE says that you've done the work. If you simply call the base class implementation, it's going to do this for you, and you'll lose the background until it gets a chance to paint.
You're not getting paint messages to the parent window for some reason. Make sure you're calling the modal in the correct manner. DoModal() works fine. Make sure you're not just creating the modal and showing it.
If your windows are children on the same dialog/window and they overlap or you have children on either dialog/window, make sure that you use clipchildren and clipsiblings (if children on a window overlap). Otherwise they'll get to paint in any order they choose artifacting all over the place.
Ensure that you're painting to memory and bitblting back to your dialog, otherwise you'll get a flashing effect.

flicker free tab control with WS_EX_COMPOSITED

I have a VS2008 C++ application for Windows XP SP3 developed using WTL 8.1. My application contains a tab control that flickers when the application border is resized.
My window hierarchy looks like this:
CFrameWindowImpl CMainFrm
|-CSplitterWindow Splitter
|-CTabView Configuration Tabs
| |-CDialogImpl Configuration View 1
| |-CDialogImpl Configuration View 2
| |-CDialogImpl Configuration View 3
|-CDialogImpl Control View
The solution I'm trying is to make the CFrameWindowImpl derived class use the WS_EX_COMPOSITED style and all windows beneath it use the WS_EX_TRANSPARENT style. Unfortunately, this makes the tab control buttons show as an empty black bar and the controls of any Configuration View to not show at all.
If I remove the WS_EX_COMPOSITED and WS_EX_TRANSPARENT styles, the form displays properly, but the CTabView and everything beneath it flickers horribly when resized.
What do I need to change to eliminate the flicker and draw the controls properly?
Thanks,
PaulH
Edit:
Got it working. I removed all the WS_EX_TRANSPARENT styles per Mark Ransom's suggestion. I put the WS_EX_COMPOSITED style on only the CTabCtrl (contained within the CTabView). Other controls get double-buffering as needed through WTL::CDoubleBufferImpl<>.
A window flickers because it gets erased before it's drawn. To eliminate this you need to disable erasing of the window entirely and use double buffering - draw the window contents into a bitmap, then copy the bitmap to the window. Because the bitmap contains the entire contents including the background, there's no need to erase anymore.
It looks like WS_EX_COMPOSITED will handle the double buffering automatically, but you still probably need to use a NULL background brush and/or handle the WM_ERASEBKGND message.
Whats not mentioned in MSDN is that the Desktop Window Manager - the component that hooks window painting on Windows Vista and 7 to perform the desktop composition necessary to get the aero glass effect - does NOT implement WS_EX_COMPOSITED.
Which means all the work you put into getting this style to work on XP, is doomed to become irrelevent on Vista or later.
The other problem with WS_EX_COMPOSITED - and why it was an optional style and not a default on XP: The double buffering only picks up painting performed during the BeginPaint / EndPaint block of the parent window. Lots of, even standard controls, perform painting outside of their WM_PAINT handlers, and as a result the backbuffer gets only partially painted.
Sadly, the result is, the only way to "eliminate" flicker in native API apps is to try to minimize it: WS_CLIPCHILDREN and WS_CLIPSIBLINGS can help if you dont have overlapping controls - to ensure that each control's area is painted only once. And ensure that the main dialog does not perform any flood filling in WM_ERASEBKGND
It is not, in my experience, possible to use double-buffering for anything that contains child controls (unless they all fully support WM_PRINT, which most do not).

Problems encountered when implement a float, translucent sub-window in MFC with C++

I have tried several methods, but problems always exist. Sometimes the sub-window didn't refresh and sometimes the sub-window will keep blink.
This is a sample project that i have written
http://rapidshare.com/files/283950611/TestProject.7z.html
My method to implement that is:
Put a scroll bar on the top of sub-window, whenever the scroll bar was dragged, the sub-window would be moved as well.
And every dialog is inherited from CDialogBase, All the drawing is done in this class, Drawer.h is a helper for drawing.
Only when the DC that user assigned is dirty, then system will redraw the window, it is used for accelerating the painting.
WS_EX_LAYERED only can be added to with top level window, not sub-window; I've tried to modify the window style from WS_CHILD to WS_OVERLAPPED, and then using layed window, and then clip the visiable area of the window, but, the result is not what I expected.
Anywhere, thank you for your advice...
Have you considered using WS_EX_LAYERED and then using UpdateLayeredWindow. It can get quite complicated but allows for things like per-pixel alpha and eliminates flicker like you are seeing.
Look here:
http://www.nuonsoft.com/blog/2009/05/27/how-to-use-updatelayeredwindow/
for more info.