static void Main ()
{
var pdf = new CGContextPDF (NSUrl.FromFilename ("demo.pdf"), new RectangleF (0, 0, 617, 792));
pdf.BeginPage (null);
pdf.SetRGBFillColor (1, 0, 0, 1);
pdf.AddArc (300, 300, 100, 0, (float) (2 * Math.PI), true);
pdf.FillPath ();
pdf.EndPage ();
pdf.Flush ();
}
public void Dispose()
{
if (context != null) {
context.EndPage ();
context.Dispose ();
context = null;
}
}
public void Open(string outputFile)
{
context = new CGContextPDF (NSUrl.FromFilename (outputFile));
}