bool OnParentWmPaint(ref Message m, BaseWndProc baseProc)
{
IntPtr hwnd = m.HWnd;
var clientRect = new NativeMethods.RECT();
UnsafeNativeMethods.GetClientRect(hwnd, ref clientRect);
ActionOnFrameRect(clientRect.ToRectangle(), rect => UnsafeNativeMethods.ValidateRect(hwnd, ref rect));
return(false);
}
void DrawParentFrame(Graphics g, IntPtr hwnd)
{
var rect = new NativeMethods.RECT();
UnsafeNativeMethods.GetClientRect(hwnd, ref rect);
var frameRect = rect.ToRectangle();
frameRect.Width--;
frameRect.Height--;
using (var pen = new Pen(this.BackColor))
{
g.DrawRectangle(pen, frameRect);
}
}
bool OnParentWmSize(ref Message m, BaseWndProc baseProc)
{
var oldRect = this.ParentForm.ClientRectangle;
baseProc(ref m);
IntPtr hwnd = m.HWnd;
var newRect = new NativeMethods.RECT();
UnsafeNativeMethods.GetClientRect(hwnd, ref newRect);
ActionOnFrameRect(oldRect, rect => UnsafeNativeMethods.InvalidateRect(hwnd, ref rect, 1));
ActionOnFrameRect(newRect.ToRectangle(), rect => UnsafeNativeMethods.InvalidateRect(hwnd, ref rect, 1));
return(true);
}