void EllipseWindow::OnPaint(wxPaintEvent& event)
{
wxPaintDC dc(this);
dc.SetBrush(*wxTRANSPARENT_BRUSH);
wxSize size = GetSize();
int x = 0;
int y = 0;
int width = size.GetWidth();
int height = size.GetHeight();
dc.DrawEllipse(x, y, width, height);
}