Rectangle in MFC

Question

I try to draw a rectangle on a mfc window using the instructions by: http://msdn.microsoft.com/en-US/library/8w4fzfxf%28v=VS.80%29.aspx . Much though I tried, the Rectangle appears on the border of the window covering the whole of it. What is the problem with the following code int the function OnDraw(CDC* pDC) ? What can be done to draw a Rectangle with particular coordinates in the window?

 CPen penBlack;
 penBlack.CreatePen(PS_SOLID, 3, RGB(0, 0, 0));
 CPen* pOldPen = pDC->SelectObject(&penBlack);

 CPoint pt(10, 10);
 CSize sz(100, 50);
 CRect myRect(pt, sz);
 GetClientRect(&myRect);

 pDC->Rectangle(&myRect);

Why do you call GetClientRect? It would seem that this call overwrites your previously set-up coordinates in myRect. — stakx - no longer contributing
You must be right, but it was suggested in the instructions. — arjacsoh
You haven't copied the instructions exactly. You've just copied and pasted parts in random order. It retrieves the client rectangle, then shrinks it by 20 pixels in each direction, then draws that rectangle. — Cody Gray

stakx - no longer contributing stakx - no longer contributing · Accepted Answer · 2011-12-19T10:46:56

Drop the call to GetClientRect.

That function will write to the rectangle object passed to it, so by calling, you're overwriting your specific coordinates that you set up just before the call using pt and sz.

Rectangle in MFC

3 Answers