am trying to move a custom button whose base class is CWnd, am using MoveWindow() method but each time i move the window the previously drawn window is still visible. i tryed to call InvalidateWindow, InvalidateRect together with UpdateWindow on the parent window but all didn't work. i also tried RedrawWindow nothing happend. how can i properly update the parent window with the new position of the button?
here is my sample code
void CCalendarCtrl::Shift()
{
RECT rc;
m_Up.GetWindowRect(&rc);
rc.top -= 20;
rc.bottom -=20;
m_Up.MoveWindow(&rc,TRUE);
RedrawWindow();
}
Call Invalidate() after movewindow().
https://social.msdn.microsoft.com/Forums/en-US/d6da8041-747c-4b31-b493-343e4516b452/are-the-coordinates-returned-by-cwndgetwindowrect-mfc-and-cwndmovewindow-mfc?forum=vcmfcatl
GetWindowRect returns screen coordinates. MoveWindow works using Client coordinates. So you need to do ScreenToClient(&rc) between the two calls.
Related
I'm currently trying to draw something outside OnPaint function. I know there are many duplicate questions on the internet, however, I failed to get any of them to work. This is entirely because of my lack of understanding of MFC.
What works inside OnPaint:
CDC* pDC = GetDC();
HDC hDC = pDC->GetSafeHdc();
CRect lDisplayRect;
GetDlgItem(IDC_DISPLAYPOS)->GetClientRect(&lDisplayRect);
GetDlgItem(IDC_DISPLAYPOS)->ClientToScreen(&lDisplayRect);
ScreenToClient(&lDisplayRect);
pDC->FillSolidRect(&lDisplayRect, GetSysColor(COLOR_3DDKSHADOW));
pDC->TextOutW(300, 300, TEXT("test"));
It fills the area of the button control I have with a defined colour.
And it prints out the "test" string without any issue.
But it won't work outside OnPaint.
I've seen numerous suggestions such as using CmemDC,CPaintDC, etc
But none of them worked outside OnPaint.
For example,
CClientDC dc(this);
dc.rectangle( ....);
does not work.
Please note that this is a temporary test code and what I am eventually trying to do is draw incoming frames from a frame grabber within my display thread (a separate thread from the main UI thread) on the DisplayPos area and my dlg object(the dialog) owns an instance of the DisplayThread class. And I'm passing HWND and displayrect upon creating the member mDisplayThread so I can draw stuff within the display thread and that's the reason why I need to be able to draw to DC outside OnPaint (DisplayThread class does not have OnPaint or inherit any class that has it).
I'm in dire need of help...Please help!
Added: I have overridden PreTranslateMessage(MSG* pMsg) and made it return without calling the default function just in case WM_ERASE msg is erasing everything, but this approach didn't work either.
For example:
void CMFCApplicationDlg::OnLButtonDown(UINT nFlags, CPoint point)
{
// TODO: Add your message handler code here and/or call default
HDC hdc = ::GetDC(m_hWnd);
Ellipse(hdc, point.x - 10, point.y - 10, point.x + 10, point.y + 10);
::ReleaseDC(m_hWnd, hdc);
CDialogEx::OnLButtonDown(nFlags, point);
}
Two important suggestions:
Do not draw outside of OnPaint. The content may be erased or painted over at the direction of OS.
Do not draw on the dialog surface. First, it is not designed for that. It may be affected by other controls or by theming, skinning, etc. Just create a window with your own window procedure, so you are in control.
I would store the information needed for drawing in you frame grabber, and cause an immediate window painting by calling RedrawWindow
I have created a Dialog Box in a c++ windows application (using ATL lib) and I have set on it three buttons. The button lie as usual at the bottom of the Dialog Box. I want by the resize of the Dialog Box, the button to retain their position at the bottom of it. In other words, they should keep a constant (low) distance from the bottom margin and the on side (right or left) of the Dialog Box. To bring this into effect, I try to move the buttons accordingly while the Dialog Box size is changed. I use the following code (as example only with the OK button), but the only result is the button to disappear during the resize. How should I modify the code in order for the button to retain its distance from the bottom and the right side of the Dialog Box?
LRESULT RenameFolderDlg::OnSize(UINT uMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled)
{
RECT r;
GetWindowRect(&r);
CWindow okB(GetDlgItem(IDOK));
RECT okR;
okB.GetWindowRect(&okR);
okB.MoveWindow( r.right - 80 , r.bottom - 40, okR.right - okR.left, okR.bottom - okR.top, 1);
return 0;
}
I use winapi. In that I use GetWindowRect to fetch cordinates of control and then use MapWindowPoints to map those rectangular coordinates on to screen. Then use SetWindowPos to position windows according to mapped rectangular coordinates.
On Google, I found MapWindowPoints for ATL. I think what you are legging in your code is mapwindowpoints. Try using that.
Hope it work....
Instead of
GetWindowRect(&r);
you shall use
GetClientRect(&r);
because the coordinates returned by GetWindowRect are relative to the upper-left corner of the screen, while MoveWindow called for a child control expects they are relative to the upper-left corner of the parent window's client area.
I am quite desperate to resolve this very annoying issue :(
I am trying to display a child window on parent window. Some time the window need to be resized. But for some reason, when I using MoveWindow function it leaves blank space on the top of the parent window. I would like to present a picture here but I can not post a picture.
Here is the code example:
HWND hwnd // Comes from external function. Was defined as WS_CHILD previously
HWND hwndParent = ::GetParent(hwnd);
RECT parentRect = {0,0,0,0};
RECT childRect = {0,0,0,0};
::GetClientRect(hwndParent, &parentRect); // Suppose it returns {0,0,600,300}
BOOL ok = ::MoveWindow(hwnd, 0, 0, 600, 300, true);
::GetClientRect(hwnd, &childRect); // Will return {0,0,584,297}
WHY ?????
What am I doing wrong? Did I forgot some flags with window initialization?!
Rather than use GetClientRect, use GetWindowRect and MapWindowPoints(NULL,hwndParent,&parentRect,2) to adjust it to the parent window coordinates. GetWindowRect will include the non-client area that MoveWindow requires.
Edit: If you want a window that doesn't have a non-client area so the window rect and the client rect are the same size, you need to trim the window styles that you apply to the window. Avoid the WS_BORDER, WS_CAPTION, WS_DLGFRAME, WS_OVERLAPPED, WS_SIZEBOX, and WS_THICKFRAME styles.
MoveWindow updates window position, while GetClientRect gets a client-area part of the window, which does not have to be the same. If your window has non-client area, then everything is fine and works as expected.
If you are still under impression that child window does not fully cover parent's client area, then the spacing belongs to the child control/window, and you need to look for ways to remove it there (control flags, parameters etc).
MoveWindow operates on window coordinates -- including non-client area (borders, title bar, etc).
GetClientRect gets the area of the client portion of the window, ignoring borders, title bar, etc.
This is where the mismatch is. If you want to MoveWindow to a desired client size, you need to just AdjustWindowRect to try and predict what to pass into MoveWindow. Note that it's not always possible, and not always accurate. For example minimum / maximum sizes of windows, menus (which can wrap to multiple lines), etc.
The problem was WS_POPUP flag to the parent window.
Very strange. As far as I know it was not suppose to have such an effect.
Thanks for everyone!
i know how to repaint the full window but i don't know how to repaint a pieace of window like i draw a squre using gdi+ than i want to change it's coordinates so i want to repaint the squre not the whole window
anyidea?
i also tried this
RECT rect2;
rect2.left=0;
rect2.top=100;
rect2.right=225;
rect2.bottom=300;
InvadiateRect(hwnd, &rect2, false);
it still repaint the whole window
One way to do this is to call InvalidateRect() with a rectangle that is large enough to cover both the old and new positions of the square you moved. Windows will then call your WM_PAINT handler to repaint the area of the screen that changed.
The UnionRect() function is helpful for calculating this repaint rectangle.
I want to change the appearance of a window's caption bar, so I decided to override the OnNcPaint() method of CMainFrame. But when I did this, I found a problem. If there is another window covering my window, and I drag the window quickly, the content of the client area of my window disappeared, which came to sight only when I stopped the dragging.
My overridden OnNcPaint() is like below:
void CMainFrame::OnNcPaint()
{
CDC* pWinDC = GetWindowDC();
//do some drawing
ReleaseDC(pWinDC);
}
Is there something wrong with my approach?
Thank you!
Unless you use a clipping region set up to exclude the client area, you can paint over it from OnNcPaint(). So... if your drawing logic can't be modified to exclude the client in some other way, set up an appropriate clipping region first:
CRect rect;
GetWindowRect(&rect);
ScreenToClient(&rect);
CRect rectClient;
GetClientRect(&rectClient);
rectClient.OffsetRect(-rect.left, -rect.top);
rect.OffsetRect(-rect.left, -rect.top);
pWinDC->ExcludeClipRect(&rectClient);
// ...
// draw stuff here
// ...
pWinDC->SelectClipRgn(NULL);