rainmeter-studio/RainmeterEditor/UI/MainWindow.xaml

<Window x:Class="RainmeterEditor.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:ui="clr-namespace:RainmeterEditor.UI"
        xmlns:ad="clr-namespace:Xceed.Wpf.AvalonDock;assembly=Xceed.Wpf.AvalonDock"
        xmlns:adlayout="clr-namespace:Xceed.Wpf.AvalonDock.Layout;assembly=Xceed.Wpf.AvalonDock"
        Title="Rainmeter Studio" Height="350" Width="525"
        ResizeMode="CanResizeWithGrip" >
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto" />
            <!-- Menu bar -->
            <RowDefinition Height="Auto" />
            <!-- Toolbar -->
            <RowDefinition />
            <!-- Dock area -->
            <RowDefinition Height="Auto" />
            <!-- Status bar -->
        </Grid.RowDefinitions>

        <!-- Menu bar -->
        <Menu Grid.Row="0" Grid.ColumnSpan="10">
            <MenuItem Header="_File">
                <MenuItem Header="_New Item..." Click="File_New_Click"/>
                <MenuItem Header="_Open..." />
                <Separator />
                <MenuItem Header="_Close" />
                <MenuItem Header="E_xit" />
            </MenuItem>
            <MenuItem Header="_Edit" />
            <MenuItem Header="_Help" />
        </Menu>

        <!-- Toolbar -->

        <!-- Grid splitter -->
        <GridSplitter Grid.Row="2" Grid.Column="1"
                      HorizontalAlignment="Stretch" VerticalAlignment="Stretch" />

        <!-- Document panel -->
        <ad:DockingManager 
            x:Name="dockingManager"
            Grid.Row="2">
            <adlayout:LayoutRoot>

                <adlayout:LayoutRoot.LeftSide>
                    <adlayout:LayoutAnchorSide>
                        <adlayout:LayoutAnchorGroup>
                            <adlayout:LayoutAnchorable Title="Toolbox" />
                        </adlayout:LayoutAnchorGroup>
                    </adlayout:LayoutAnchorSide>
                </adlayout:LayoutRoot.LeftSide>

                <adlayout:LayoutPanel Orientation="Horizontal">
                    <adlayout:LayoutDocumentPane x:Name="documentPane" />

                    <adlayout:LayoutAnchorablePaneGroup DockWidth="150" Orientation="Vertical">
                        <adlayout:LayoutAnchorablePane>
                            <adlayout:LayoutAnchorable Title="Skins">
                                <ui:SkinsPanel />
                            </adlayout:LayoutAnchorable>
                            <adlayout:LayoutAnchorable Title="Outline" />
                        </adlayout:LayoutAnchorablePane>
                        <adlayout:LayoutAnchorablePane>
                            <adlayout:LayoutAnchorable Title="Properties" />
                        </adlayout:LayoutAnchorablePane>
                    </adlayout:LayoutAnchorablePaneGroup>
                </adlayout:LayoutPanel>
            </adlayout:LayoutRoot>
        </ad:DockingManager>

        <!-- Status bar -->
        <StatusBar Grid.Row="3" Grid.ColumnSpan="10">

            <ProgressBar Name="statusProgress" 
                         Width="64" Height="8" 
                         IsIndeterminate="True" 
                         Visibility="Collapsed" />
            
            <TextBlock Name="statusMessage">Ready</TextBlock>
        </StatusBar>
    </Grid>
</Window>