protected override void OnResize(EventArgs e)
{
base.OnResize(e);
// Invalidate none client area
HeaderPanelNativeMethods.RedrawWindow(this.Handle, IntPtr.Zero, IntPtr.Zero,
0x0400 /*RDW_FRAME*/ | 0x0100 /*RDW_UPDATENOW*/ | 0x0001 /*RDW_INVALIDATE*/);
}
protected override void WndProc(ref Message m)
{
switch (m.Msg)
{
case WM_NCCALCSIZE:
WmNCCalcSize(ref m);
break;
case WM_NCPAINT:
IntPtr hDC = HeaderPanelNativeMethods.GetWindowDC(m.HWnd);
if (hDC != IntPtr.Zero)
{
using (Graphics canvas = Graphics.FromHdc(hDC))
{
PaintNonClientArea(canvas);
}
HeaderPanelNativeMethods.ReleaseDC(m.HWnd, hDC);
}
m.Result = IntPtr.Zero;
break;
}
base.WndProc(ref m);
}