Paint problem when handling WM_CTLCOLOREDIT
I have an non read only edit control for which I need to change colors so I handle WM_CTLCOLOREDIT. It works well when I am typing continuously but the problem is when I hit backspace or delete or even start typing from the middle of an existing text, the display is all junked up. That remains untill I cause a repaint by resizing the parent etc. How to fix this?
Edit: Some detail. The pr开发者_Go百科oblem seems only when the background color is set and not when just the text color is set. The code looks like this
ON_MESSAGE(WM_CTLCOLOREDIT, OnEditColor)
LRESULT CMyWindow::OnEditColor(WPARAM wp, LPARAM lp)
{
HDC hdc = (HDC)wp;
HWND hwnd = (HWND)lp;
if(hwnd == m_edit.GetSafeHwnd())
{
// SetBkMode(hdc, TRANSPARENT);
MyControlInfo*pcti;// accessed from somewhere
SetTextColor(hdc, pcti->theme.clrText);
// return (LRESULT)pcti->brush.GetSafeHandle();
}
return 0;
}
Thanks
I rather doubt that this is caused by this code. It is the kind of problem you get when you try to subclass the edit control and override painting. Windows version 2 having to run on a 386SUX and 20 years of appcompat prevented Microsoft from fixing this control so it only draws itself in the WM_PAINT message handler. It indeed draws directly to the screen when you backspace. There's no workaround for it.
Same comment applies as in your previous question, use a real edit control.
You should set a background color with SetBkColor (And don't use SetBkMode) and return a valid brush. (You don't know how the control does its painting, it is free to use ExtTextOut with ETO_OPAQUE etc)
http://msdn.microsoft.com/en-us/library/bb761691(v=vs.85).aspx
Return Value
If an application processes this message, it must return the handle of a brush. The system uses the brush to paint the background of the edit control.
So try something like:
return static_cast<LRESULT>(::GetSysColorBrush(COLOR_WINDOW));
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