protected override void WndProc(ref Message m)
{
if ((m.Msg == NativeMethods.WM_NCHITTEST) && SizingGrip)
{
// if we're within the grip bounds tell windows
// that we're the bottom right of the window.
Rectangle sizeGripBounds = SizeGripBounds;
int x = NativeMethods.Util.LOWORD(m.LParam);
int y = NativeMethods.Util.HIWORD(m.LParam);
if (sizeGripBounds.Contains(PointToClient(new Point(x, y))))
{
HandleRef rootHwnd = WindowsFormsUtils.GetRootHWnd(this);
// if the main window isnt maximized - we should paint a resize grip.
// double check that we're at the bottom right hand corner of the window.
if (rootHwnd.Handle != IntPtr.Zero && !UnsafeNativeMethods.IsZoomed(rootHwnd))
{
// get the client area of the topmost window. If we're next to the edge then
// the sizing grip is valid.
NativeMethods.RECT rootHwndClientArea = new NativeMethods.RECT();
UnsafeNativeMethods.GetClientRect(rootHwnd, ref rootHwndClientArea);
// map the size grip FROM statusStrip coords TO the toplevel window coords.
NativeMethods.POINT gripLocation;
if (RightToLeft == RightToLeft.Yes)
{
gripLocation = new NativeMethods.POINT(SizeGripBounds.Left, SizeGripBounds.Bottom);
}
else
{
gripLocation = new NativeMethods.POINT(SizeGripBounds.Right, SizeGripBounds.Bottom);
}
UnsafeNativeMethods.MapWindowPoints(new HandleRef(this, this.Handle), rootHwnd, gripLocation, 1);
int deltaBottomEdge = Math.Abs(rootHwndClientArea.bottom - gripLocation.y);
int deltaRightEdge = Math.Abs(rootHwndClientArea.right - gripLocation.x);
if (RightToLeft != RightToLeft.Yes)
{
if ((deltaRightEdge + deltaBottomEdge) < 2)
{
m.Result = (IntPtr)NativeMethods.HTBOTTOMRIGHT;
return;
}
}
}
}
}
base.WndProc(ref m);
}