how to set width for Avalondock LayoutAnchorablePane

I have a set of LayoutAnchorablePaneGroup as below,

 <xcad:LayoutRoot>
     <xcad:LayoutPanel Orientation="Horizontal">
                <xcad:LayoutAnchorablePaneGroup Orientation="Horizontal" >
                    <xcad:LayoutAnchorablePane  DockWidth="150">
                        <xcad:LayoutAnchorable Title="Folder" CanClose="False">
                            ...
                        </xcad:LayoutAnchorable>
                    </xcad:LayoutAnchorablePane>
                </xcad:LayoutAnchorablePaneGroup>
                <xcad:LayoutAnchorablePaneGroup Orientation="Horizontal" >
                    <xcad:LayoutAnchorablePane DockWidth="450">
                        <xcad:LayoutAnchorable Title="Documents" CanClose="False">
                            ...
                        </xcad:LayoutAnchorable>
                    </xcad:LayoutAnchorablePane>
                </xcad:LayoutAnchorablePaneGroup>
                <xcad:LayoutAnchorablePaneGroup Orientation="Vertical" >
                    <xcad:LayoutAnchorablePane DockWidth="200">
                        <xcad:LayoutAnchorable Title="Properties" CanClose="False">
                            ...
                        </xcad:LayoutAnchorable>
                    </xcad:LayoutAnchorablePane>
                    <xcad:LayoutAnchorablePane >
                        <xcad:LayoutAnchorable Title="Search" CanClose="False">
                            ...
                        </xcad:LayoutAnchorable>
                    </xcad:LayoutAnchorablePane>
                </xcad:LayoutAnchorablePaneGroup>
                <xcad:LayoutAnchorablePaneGroup Orientation="Horizontal" >
                    <xcad:LayoutAnchorablePane DockWidth="*">
                        <xcad:LayoutAnchorable Title="Viewer" CanClose="False">
                            ...
                        </xcad:LayoutAnchorable>
                    </xcad:LayoutAnchorablePane>
                </xcad:LayoutAnchorablePaneGroup>
     </xcad:LayoutPanel>
 </xcad:LayoutRoot>

I want to set the width of each LayoutAnchorablePane. I have tried setting it on Group Level no effect.

note: I dont have a LayoutDocumentPane if i have added LayoutDocumentPane i am able to get the width properly.

Any Help

Solution

I have done some research and came up with the solution with Grid and DockPanel

  <DockPanel Grid.Row="2" FlowDirection="LeftToRight" LastChildFill="True"  SnapsToDevicePixels="True" WindowChrome.ResizeGripDirection="TopLeft" >
    <xcad:DockingManager DockPanel.Dock="Left" Grid.Row="2" BorderBrush="Black" BorderThickness="1" >
        <xcad:LayoutRoot>
            <xcad:LayoutPanel Orientation="Horizontal">
                <xcad:LayoutAnchorablePaneGroup Orientation="Horizontal" DockMinWidth="150" >
                    <xcad:LayoutAnchorablePane >
                        <xcad:LayoutAnchorable Title="Folder">
                               ...
                        </xcad:LayoutAnchorable>
                    </xcad:LayoutAnchorablePane>
                </xcad:LayoutAnchorablePaneGroup>
                <xcad:LayoutAnchorablePaneGroup Orientation="Horizontal" DockMinWidth="450" >
                    <xcad:LayoutAnchorablePane >
                        <xcad:LayoutAnchorable Title="Documents" >
                                ...
                        </xcad:LayoutAnchorable>
                    </xcad:LayoutAnchorablePane>
                </xcad:LayoutAnchorablePaneGroup>
                <xcad:LayoutAnchorablePaneGroup Orientation="Vertical" DockMinWidth="200" >
                    <xcad:LayoutAnchorablePane >
                        <xcad:LayoutAnchorable Title="Properties" >
                            ...
                        </xcad:LayoutAnchorable>
                    </xcad:LayoutAnchorablePane>
                    <xcad:LayoutAnchorablePane >
                        <xcad:LayoutAnchorable Title="Search" >
                            ...
                        </xcad:LayoutAnchorable>
                    </xcad:LayoutAnchorablePane>
                </xcad:LayoutAnchorablePaneGroup> 
                </xcad:LayoutPanel>
        </xcad:LayoutRoot>


    </xcad:DockingManager>  
</DockPanel>