Dear Jarrey thanks for the reply,
I took your advice and did this:
this.statusBar = new System.Windows.Controls.Primitives.StatusBar();
DockPanel myDockPanel = new DockPanel();
myDockPanel.Children.Add(this.canvas);
myDockPanel.Children.Add(this.statusBar);
this.elementHost.Child = myDockPanel;
But somehow statusbar fills up the whole area and I cant see the canvas. If I comment out adding statusbar as a child then I see canvas filling up the area.
Whats going on here?