Why does overriding the WPF [removed] method fail to draw to the screen?

Question

I noticed that when overriding the System.Windows.Window OnRender method fails to draw to the screen. I\'m sure there\'s a good reason for this but was unable to find the explan

Answer 1

just as a check, does the snippet work with the dc.Draw... lines removed (i.e. is it the act of overriding or the additional draw commands that cause the issue)?

I found a link that suggests that simply re-ordering the calls may solve the issue (i.e. doing the dc.Draw... calls before calling base.OnRender(dc)).

http://www.codeproject.com/Messages/3356653/Override-OnRender-class-inherits-frameworkelement.aspx