Question

以下是我在XAML中的代码：

        <!-- ItemsControl to print all the GDTs on the map as an overlay on tiles -->
        <ItemsControl ItemsSource="{Binding GDTs, Mode=OneWay}" Grid.ColumnSpan="3" Grid.RowSpan="3" Panel.ZIndex="7">
          <ItemsControl.ItemsPanel>
            <ItemsPanelTemplate>
              <Canvas ClipToBounds="True" SnapsToDevicePixels="true"/>
            </ItemsPanelTemplate>
          </ItemsControl.ItemsPanel>
          <ItemsControl.ItemContainerStyle>
            <Style TargetType="ContentPresenter">
              <Setter Property="Canvas.Left"  Value="{Binding DistanceToLeft}"/>
              <Setter Property="Canvas.Top"   Value="{Binding DistanceToTop}"/>
              <Setter Property="ContentTemplate">
                <Setter.Value>
                  <DataTemplate>
                    <Grid>
                      <userControls:CommIndicator CommConfig="eDt" DtAntennaMode="eDirectional" DtAzimuth="{Binding Yaw}"/>
                      <Image HorizontalAlignment="Center" VerticalAlignment="Center" Source="{Binding SourcePath}" Width="{Binding Width}"/>
                      <Rectangle Height="{Binding Height}" Width="{Binding Width}" Stroke="Orange" StrokeThickness="2"/>
                      <Ellipse Height="4" Width="4" Fill="Orange" HorizontalAlignment="Center" VerticalAlignment="Center"/>
                    </Grid>
                  </DataTemplate>
                </Setter.Value>
              </Setter>
            </Style>
          </ItemsControl.ItemContainerStyle>
        </ItemsControl>

除了刚刚在UserControl（CommIndicator）中添加的那个绑定之外，其中的所有绑定都有效： DtAzimuth =“{Binding Yaw}”。

我在Snoop中看到的关于该绑定的错误是这样的：“System.Windows.Data错误：40：BindingExpression路径错误：在'对象'''CommIndicator'上找不到'Yaw'属性（Name = ''）'。BindingExpression：Path = Yaw; DataItem ='CommIndicator'（Name =''）;目标元素是'CommIndicator'（Name =''）;目标属性是'DtAzimuth'（类型'Int32'）“< / em>的

有没有办法强制绑定来检查ItemsControl“currentItem”？

编辑1：这是我的UserControl的XAML：

<UserControl x:Class="UserControls.CommIndicator" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:ed="http://schemas.microsoft.com/expression/2010/drawing" xmlns:userControls="clr-namespace:UserControls" DataContext="{Binding RelativeSource={RelativeSource Self}}" SnapsToDevicePixels="True"> <UserControl.Resources> <ResourceDictionary> <userControls:CommConfigToVisibility x:Key="CommConfigToVisibility"/> <userControls:AntennaModeToAngle x:Key="AntennaModeToAngle"/> <userControls:AntennaModeToColor x:Key="AntennaModeToColor"/> </ResourceDictionary> </UserControl.Resources> <Grid Width="100" Height="100">    <Grid HorizontalAlignment="Center" VerticalAlignment="Center" Width="100" Height="100" Visibility="{Binding CommConfig, Converter={StaticResource CommConfigToVisibility}, ConverterParameter={x:Static userControls:CommType.eDataRelay}}"> <Ellipse Width="100" Height="100" Stroke="Black" StrokeThickness="7"/> <ed:Arc Width="99" Height="99" Fill="SlateGray" StartAngle="0" EndAngle="360" ArcThickness="5"/> <ed:Arc Width="99" Height="99" Stretch="None" ArcThickness="6" Fill="{Binding DrAntennaMode, Converter={StaticResource AntennaModeToColor}}" StartAngle="{Binding DrAntennaMode, Converter={StaticResource AntennaModeToAngle}, ConverterParameter={x:Static userControls:AngleType.eStartAngle}}" EndAngle="{Binding DrAntennaMode, Converter={StaticResource AntennaModeToAngle}, ConverterParameter={x:Static userControls:AngleType.eEndAngle}}"/> <Grid.LayoutTransform> <RotateTransform Angle="{Binding DrAzimuth}"/> </Grid.LayoutTransform> </Grid>  <Grid HorizontalAlignment="Center" VerticalAlignment="Center" Width="90" Height="90" Visibility="{Binding CommConfig, Converter={StaticResource CommConfigToVisibility}, ConverterParameter={x:Static userControls:CommType.eDataTransmitter}}"> <Ellipse Width="88" Height="88" Stroke="Black" StrokeThickness="7"/> <ed:Arc Width="87" Height="87" Fill="SlateGray" StartAngle="0" EndAngle="360" ArcThickness="5"/> <ed:Arc Width="87" Height="87" Stretch="None" ArcThickness="6" Fill="{Binding DtAntennaMode, Converter={StaticResource AntennaModeToColor}}" StartAngle="{Binding DtAntennaMode, Converter={StaticResource AntennaModeToAngle}, ConverterParameter={x:Static userControls:AngleType.eStartAngle}}" EndAngle="{Binding DtAntennaMode, Converter={StaticResource AntennaModeToAngle}, ConverterParameter={x:Static userControls:AngleType.eEndAngle}}"/> <Grid.LayoutTransform> <RotateTransform Angle="{Binding DtAzimuth}"/> </Grid.LayoutTransform> </Grid> </Grid> </UserControl>

Answer 1

删除它：

DataContext="{Binding RelativeSource={RelativeSource Self}}"

来自UserControl的

，并添加：

<UserControl ...
             x:Name="view">

并更改usecontrol中的所有绑定以使用ElementName，如下所示：

{Binding ElementName=view, Path=DtAntennaMode, Converter={StaticResource AntennaModeToColor}}"

此外，似乎有很多转换器在那里。我强烈建议您将所有这些更改为使用ControlTemplate，并在其中放置ControlTemplate.Triggers并删除转换器和DataContext黑客的需要。

ItemsControl中的绑定不会冒泡到ItemsSource中的项目

1 个答案: