Is there any way resizing settingPane

I work it out, there are two problems:

1. there is a panel in setting pane which contains a radTitleBar and a pageview, the problem is the DockStyle of the panel is  not DockStyle.Fill, so when I set the size of setting pane the panel does not resize itself. I have to set Dock property manually.

RadPanel radPanel = radDiagram1.DiagramElement.SettingsPane.Controls.OfType<RadPanel>().First();
radPanel.Dock = DockStyle.Fill;

2. the dock style of the titlebar should be dockStyle.Top, but it is not,  so I have to set the Dock property to Top

var titleBar = radPanel.Controls.OfType<RadTitleBar>().First();
titleBar.Dock = DockStyle.Top;

After these two steps,  I can resize setting pane via 

radDiagram1.DiagramElement.SettingsPane.Size and everything works