To change a NavBarControl’s view in code, you should create a new instance of the required view object (SideBarView, NavigationPaneView, or ExplorerBarView) and assign it to the NavBarControl.View property.
using DevExpress.Xpf.NavBar;
//...
NavigationPaneView navPaneView = new NavigationPaneView();
navPaneView.ActiveGroupMinHeight = 200;
navBarControl1.View = navPaneView;
Imports DevExpress.Xpf.NavBar
'...
Dim navPaneView As New NavigationPaneView()
navPaneView.ActiveGroupMinHeight = 200
navBarControl1.View = navPaneView