Question

How can I programmatically add UIElements to canvas in Silverlight 4?

But nothing happens. When I check for the existence of the image it is there
but nothing shows.

wtf?

Button btn = new Button();
btn.Content = "Button";
Canvas.SetLeft(btn, 450);
Canvas.SetTop(btn, 100);
Canvas1.Resources.Add("btn1", btn);
Canvas1.UpdateLayout(); 

Answer 1

You want to use Children, not Resources.

Button btn = new Button();
btn.Content = "Button";
Canvas.SetLeft(btn, 450);
Canvas.SetTop(btn, 100);
Canvas1.Children.Add(btn);