Adding Button in StatusBar !

How do I do this in code? (No XAML file)

I tried:

            this.buttonOK.Content = "OK";
            this.canvasPanel.Children.Add(this.buttonOK);
            this.buttonOK.Height = 30;
            this.buttonOK.HorizontalAlignment = System.Windows.HorizontalAlignment.Right;
            this.buttonOK.VerticalAlignment = VerticalAlignment.Bottom;

But is displays the button on top left corner!!!!?