Silverlight ZOrder在Bing控件中不適用於我

Question

我試圖讓我的彈出窗口小部件位於地圖的頂部，但設置Canvas.ZOrder沒有幫助。

這裏是XAML：

<m:Map x:Name="MainMap" 
      Margin="0,6,3,3" 
      ZoomLevel="{Binding MapZoomLevel, Mode=TwoWay}" 
      Center="{Binding MapCenter, Mode=TwoWay}" 
      CopyrightVisibility="Collapsed" 
      CredentialsProvider="{Binding BingCredentialsProvider}" 
      UseInertia="True" 
      Mode="Road" Grid.Column="2" Grid.Row="1"> 
      <m:MapItemsControl ItemsSource="{Binding Source={StaticResource WorkLayerData}}"> 
       <m:MapItemsControl.ItemTemplate> 
        <DataTemplate> 
         <Canvas 
          m:MapLayer.Position="{Binding Location}"> 
          <Button         
           Width="{Binding PushpinWidth}" Height="{Binding PushpinWidth}" 
           Margin="{Binding PushpinMargin}" 
           Style="{StaticResource LooklessButtonStyle}" 
           Command="{Binding DataContext.SelectedPushpinChangedCommand, ElementName=LayoutRoot}" 
           CommandParameter="{Binding}" 
           Cursor="Hand"> 
           <Ellipse 
            Width="{Binding PushpinWidth}" Height="{Binding PushpinWidth}" Stroke="Black" Fill="{Binding IsGPSDataRecent, Converter={StaticResource BoolToGreenRedBrushConverter}}" StrokeThickness="1"> 
            <ToolTipService.ToolTip> 
             <TextBlock Text="{Binding DeviceId}" /> 
            </ToolTipService.ToolTip> 
           </Ellipse> 
          </Button> 

          <!-- Show black dot over actual GPS point --> 
          <Ellipse 
           Width="10" Height="10" Stroke="Black" Fill="Black" StrokeThickness="1" 
           Margin="-5,-5,0,0" 
           Visibility="{Binding IsSelected, Converter={StaticResource BoolToVisibilityConverter}}" /> 

          <Border 
           Width="200" 
           BorderThickness="1" BorderBrush="DarkGray" 
           Visibility="{Binding IsSelected, Converter={StaticResource BoolToVisibilityConverter}}"> 
           <Border.Effect> 
            <DropShadowEffect BlurRadius="5" Color="#FF000000" Opacity="0.5" ShadowDepth="2" /> 
           </Border.Effect> 
           <ContentControl Template="{StaticResource TrackedAssetControlTemplate}" /> 
          </Border> 
         </Canvas>            
        </DataTemplate> 
       </m:MapItemsControl.ItemTemplate> 
      </m:MapItemsControl> 
     </m:Map> 

我試圖設置zIndex的上邊界，但沒有運氣。 下面是它的外觀時IsSelected =真（看其他點與zIndex的更高頂部）

Answer 1

爲了帶來正面的項目在MapItemsControl有必要設定該項目的Z-索引容器。您可以通過從MapItemsControl的ItemContainerGenerator中檢索項目容器來在代碼後面執行此操作。

如果您不需要，可以將附加的幫助屬性應用於DataTemplate中的頂級容器（Canvas）以獲取地圖項目。由於此Canvas是項目容器的直接子項，所以助手屬性必須設置Canvas的可視父項的ZIndex。如果這聽起來有些不可思議，這裏被稱爲MapItem的附加屬性的代碼，在一個輔助類：

public class MapItem 
{ 
    public static readonly DependencyProperty ZIndexProperty = 
     DependencyProperty.RegisterAttached("ZIndex", typeof(int), 
      typeof(MapItem), new PropertyMetadata(ZIndexChanged)); 

    public static int GetZIndex(DependencyObject obj) 
    { 
     return (int)obj.GetValue(ZIndexProperty); 
    } 

    public static void SetZIndex(DependencyObject obj, int value) 
    { 
     obj.SetValue(ZIndexProperty, value); 
    } 

    private static void ZIndexChanged(DependencyObject obj, DependencyPropertyChangedEventArgs e) 
    { 
     // set ZIndex on parent of obj 
     Canvas.SetZIndex((UIElement)VisualTreeHelper.GetParent(obj), (int)e.NewValue); 
    } 
} 

在你的DataTemplate現在你可以或許通過使用適當的輔助屬性綁定到你的虛擬機性能，一個綁定轉換器：

<DataTemplate x:Key="MapItemDataTemplate"> 
    <!-- setting the helper property MapItem.ZIndex on Canvas 
     sets the Canvas.ZIndex property on the item container --> 
    <Canvas local:MapItem.ZIndex="{Binding ...}"> 
     ... 
    </Canvas> 
</DataTemplate>