Silverlight中的嵌套ItemsControl和高度调整

Question

对于我正在开发的应用程序，我有一些嵌套的ItemsControls，在以下布局中使用了一些不相关的项目以简洁起见：

ItemsControl（GroupItemsControl）   - ItemPanel：具有垂直方向的StackPanel   - ItemTemplate：ScrollViewer里面有一个ItemsControl（SliceItemsControl）      - ItemPanel：画布*      - ItemTemplate：包含ItemsControl的Canvas（EventItemsControl）        - ItemPanel：自定义面板，在测量/布局后最终将达到设定高度        - ItemTemplat：包含矩形和文本块的StackPanel，水平方向

问题在于我需要将标有“*”的画布大小调整到嵌套两层深度的自定义面板的高度（实际上它需要是最高的SliceItemsControl项的高度（自定义）它包含在其中。）目标是滚动查看器可以向左/向右滚动，但滚动查看器的高度将调整，以便不需要垂直滚动。

请注意，我正在尝试使用MVVM（我的第一次），所以我试图尽可能多地将数据绑定到ViewModel。

布局的完整xaml：

<navigation:Page.Resources>
        <SPARTA_ViewModel:FlexCalendar x:Key="FlexCalendarDataSource" d:IsDataSource="True"/>
        <SPARTA_HelperClasses:DateToOffsetConverter x:Key="DateOffsetConverter"/>
        <SPARTA_HelperClasses:DaysToPixelsConverter x:Key="DatePixelConverter"/>
        <ItemsPanelTemplate x:Key="GroupsItemPanel">
            <StackPanel/>
        </ItemsPanelTemplate>
        <ItemsPanelTemplate x:Key="SlicesPanelTemplate">
            <Canvas />
        </ItemsPanelTemplate>
    <ItemsPanelTemplate x:Key="EventsPanelTemplate">
        <SPARTA_HelperClasses:FlexCalendarEventPanel x:Name="EventPanel" SizeChanged="EventPanel_SizeChanged" />
    </ItemsPanelTemplate>
    <DataTemplate x:Key="EventsItemTemplate">
        <StackPanel Orientation="Horizontal"
                    >
            <Rectangle Fill="Green" Width="{Binding Length}" Height="20">
                <ToolTipService.ToolTip>
                    <TextBlock Text="{Binding StartDate}"></TextBlock>
                </ToolTipService.ToolTip>
            </Rectangle>
            <TextBlock Text="{Binding EventName}"></TextBlock>
        </StackPanel>
    </DataTemplate>
        <DataTemplate x:Key="SlicesItemTemplate">
            <Canvas Width="{Binding Path=SliceSize, Source={StaticResource FlexCalendarDataSource}, Converter={StaticResource DatePixelConverter}, ConverterParameter={StaticResource FlexCalendarDataSource}}" 
                Height="300" 
                Background="#FF700505" 
                HorizontalAlignment="Left" 
                VerticalAlignment="Top" 
                Canvas.Left="{Binding Left}" 
                x:Name="EventAreaCanvas">
            <ToolTipService.ToolTip>
                <TextBlock Text="{Binding SliceRange.StartDate}"></TextBlock>
            </ToolTipService.ToolTip>
            <SPARTA_HelperClasses:EventsItemsCollection x:Name="EventsItemsControl" ItemsSource="{Binding Events, Mode=OneWay}" ItemsPanel="{StaticResource EventsPanelTemplate}" ItemTemplate="{StaticResource EventsItemTemplate}"/>
            </Canvas>
        </DataTemplate>
        <DataTemplate x:Key="GroupsItemTemplate">
            <StackPanel Orientation="Horizontal" Margin="5">
                <Border Width="{Binding GroupColWidth, Mode=OneWay, Source={StaticResource FlexCalendarDataSource}}" BorderBrush="Black" BorderThickness="1" MinHeight="50" CornerRadius="3" Background="#FF629433">
                    <TextBlock Text="{Binding Title, Mode=OneWay}" TextWrapping="Wrap" HorizontalAlignment="Center" VerticalAlignment="Center"/>
                </Border>
                <ScrollViewer MinHeight="50" 
                          HorizontalContentAlignment="Left" 
                          VerticalContentAlignment="Top" 
                          Padding="1" 
                          VerticalScrollBarVisibility="Auto" 
                          Width="750" 
                           >
            <SPARTA_HelperClasses:SliceItemsCollection 
                    x:Name="SlicesItemsControl" 
                    ItemsSource="{Binding Slices, Mode=OneWay}" 
                    ItemsPanel="{StaticResource SlicesPanelTemplate}" 
                    ItemTemplate="{StaticResource SlicesItemTemplate}"
                    Height="500"/>

                </ScrollViewer>
            </StackPanel>
        </DataTemplate>
    </navigation:Page.Resources>
<Grid x:Name="LayoutRoot" Height="768" Margin="0" Width="1024" DataContext="{Binding Source={StaticResource FlexCalendarDataSource}}" VerticalAlignment="Top">

    <Grid.RowDefinitions>
        <RowDefinition Height="45"/>
        <RowDefinition />
        <RowDefinition Height="48"/>
    </Grid.RowDefinitions>
    <ItemsControl x:Name="GroupsItemsControl" 
                  Margin="0" 
                  Grid.Row="1" 
                  DataContext="{StaticResource FlexCalendarDataSource}" 
                  ItemsSource="{Binding Groups, Mode=OneWay}" 
                  ItemsPanel="{StaticResource GroupsItemPanel}" 
                  ItemTemplate="{StaticResource GroupsItemTemplate}" 
                  HorizontalContentAlignment="Left" 
                  VerticalContentAlignment="Top">

    </ItemsControl>
    <TextBlock Margin="0" Text="{Binding Title, Mode=OneWay}" TextWrapping="Wrap" d:LayoutOverrides="Height" HorizontalAlignment="Center" VerticalAlignment="Center" FontWeight="Bold" TextDecorations="Underline" FontSize="24"/>
    <Button x:Name="btnLoad" HorizontalAlignment="Left" VerticalAlignment="Top" Width="75" Content="Load Data"/>
    <TextBlock x:Name="txtVisibleDate" HorizontalAlignment="Center" VerticalAlignment="Top" Width="75" Text="{Binding VisibleDate}"/>
</Grid>