Resize docked panel from code

I created a panel for my plugin with Rhino.UI and docked it on the left with RhinoWindows.DockBar.Dock:

var type = typeof(Dialog.dPartExplorerPanel);
Panels.OpenPanel(type.GUID);
DockBar.Dock(Panels.PanelDockBar(type.GUID), DockBarDockLocation.Left);

The result is as awaited:

If I click on one of green buttons, there should be a section appearing on the right from the buttons. I want the dockbar to resize so that the new section is seen. I tried to resize the panel, but this only pushes the borders of the panel and not the whole dock bar. Using Eto.Forms.Control.Parent doesn’t work as well.
Is it possible to implement the functionality I need and how could one do this?

Vladyslav:

I have not found a way to adjust a panel size in code. In a way this does make a lot of since. You can do anything you want inside your panel. For example arrange your blocks so they stack depending on the user adjusting the panel size but I believe McNeel wants to give control of the panel outside dimension to the user not the Plug-in designer.

Best;

Steve