在DataTemplate中的ContextMenu中绑定根项属性

Question

问题似乎在于ContextMenu是一个孤立的孩子，并且没有视觉或逻辑父元素，我尝试使用PlacementTarget设置DataContext但没有运气。

<DataTemplate x:Key="ODIF.Device">
        <Button HorizontalContentAlignment="Stretch" Background="WhiteSmoke" Padding="10,1" ContextMenuService.Placement="Right" VerticalContentAlignment="Stretch" Tag="{Binding ElementName=page}">
            <Button.BorderBrush>
                <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                    <GradientStop Color="#FFC9C9C9" Offset="1"/>
                    <GradientStop Color="WhiteSmoke" Offset="0"/>
                </LinearGradientBrush>
            </Button.BorderBrush>
            <i:Interaction.Behaviors>
                <local:DropDownButtonBehavior/>
            </i:Interaction.Behaviors>
            <Button.ContextMenu>
                <ContextMenu ItemTemplate="{StaticResource ODIF.Channel}" DataContext="{Binding RelativeSource={RelativeSource Self}, Path=PlacementTarget}">
                    <ContextMenu.Style>
                        <Style TargetType="ContextMenu">
                            <Style.Triggers>
                                <MultiDataTrigger>
                                    <MultiDataTrigger.Conditions>
                                        <!--<Condition Binding="{Binding Converter={StaticResource TypeOfConverter}}" Value="{x:Type ODIF:InputDevice}" />-->
                                        <Condition Binding="{Binding inputDevicesInputChannelsVisible, ElementName=page}" Value="True" />
                                        <Condition Binding="{Binding inputDevicesOutputChannelsVisible, ElementName=page}" Value="True" />
                                    </MultiDataTrigger.Conditions>
                                    <MultiDataTrigger.Setters>
                                        <Setter Property="ItemsSource">
                                            <Setter.Value>
                                                <MultiBinding>
                                                    <MultiBinding.Converter>
                                                        <local:CompositeCollectionConverter/>
                                                    </MultiBinding.Converter>
                                                    <Binding Path="InputChannels"/>
                                                    <Binding Path="OutputChannels"/>
                                                </MultiBinding>
                                            </Setter.Value>
                                        </Setter>
                                    </MultiDataTrigger.Setters>
                                </MultiDataTrigger>
                                <MultiDataTrigger>
                                    <MultiDataTrigger.Conditions>
                                        <!--<Condition Binding="{Binding Converter={StaticResource TypeOfConverter}}" Value="{x:Type ODIF:InputDevice}" />-->
                                        <Condition Binding="{Binding inputDevicesInputChannelsVisible, ElementName=page}" Value="False" />
                                        <Condition Binding="{Binding inputDevicesOutputChannelsVisible, ElementName=page}" Value="True" />
                                    </MultiDataTrigger.Conditions>
                                    <MultiDataTrigger.Setters>
                                        <Setter Property="ItemsSource">
                                            <Setter.Value>
                                                <Binding Path="OutputChannels"/>
                                            </Setter.Value>
                                        </Setter>
                                    </MultiDataTrigger.Setters>
                                </MultiDataTrigger>
                                <MultiDataTrigger>
                                    <MultiDataTrigger.Conditions>
                                        <!--<Condition Binding="{Binding Converter={StaticResource TypeOfConverter}}" Value="{x:Type ODIF:InputDevice}" />-->
                                        <Condition Binding="{Binding inputDevicesInputChannelsVisible, ElementName=page}" Value="True" />
                                        <Condition Binding="{Binding inputDevicesOutputChannelsVisible, ElementName=page}" Value="False" />
                                    </MultiDataTrigger.Conditions>
                                    <MultiDataTrigger.Setters>
                                        <Setter Property="ItemsSource">
                                            <Setter.Value>
                                                <Binding Path="InputChannels"/>
                                            </Setter.Value>
                                        </Setter>
                                    </MultiDataTrigger.Setters>
                                </MultiDataTrigger>

                                <MultiDataTrigger>
                                    <MultiDataTrigger.Conditions>
                                        <!--<Condition Binding="{Binding Converter={StaticResource TypeOfConverter}}" Value="{x:Type ODIF:OutputDevice}" />-->
                                        <Condition Binding="{Binding outputDevicesInputChannelsVisible, ElementName=page}" Value="True" />
                                        <Condition Binding="{Binding outputDevicesOutputChannelsVisible, ElementName=page}" Value="True" />
                                    </MultiDataTrigger.Conditions>
                                    <MultiDataTrigger.Setters>
                                        <Setter Property="ItemsSource">
                                            <Setter.Value>
                                                <MultiBinding>
                                                    <MultiBinding.Converter>
                                                        <local:CompositeCollectionConverter/>
                                                    </MultiBinding.Converter>
                                                    <Binding Path="InputChannels"/>
                                                    <Binding Path="OutputChannels"/>
                                                </MultiBinding>
                                            </Setter.Value>
                                        </Setter>
                                    </MultiDataTrigger.Setters>
                                </MultiDataTrigger>
                                <MultiDataTrigger>
                                    <MultiDataTrigger.Conditions>
                                        <!--<Condition Binding="{Binding Converter={StaticResource TypeOfConverter}}" Value="{x:Type ODIF:OutputDevice}" />-->
                                        <Condition Binding="{Binding outputDevicesInputChannelsVisible, ElementName=page}" Value="False" />
                                        <Condition Binding="{Binding outputDevicesOutputChannelsVisible, ElementName=page}" Value="True" />
                                    </MultiDataTrigger.Conditions>
                                    <MultiDataTrigger.Setters>
                                        <Setter Property="ItemsSource">
                                            <Setter.Value>
                                                <Binding Path="OutputChannels"/>
                                            </Setter.Value>
                                        </Setter>
                                    </MultiDataTrigger.Setters>
                                </MultiDataTrigger>
                                <MultiDataTrigger>
                                    <MultiDataTrigger.Conditions>
                                        <!--<Condition Binding="{Binding Converter={StaticResource TypeOfConverter}}" Value="{x:Type ODIF:OutputDevice}" />-->
                                        <Condition Binding="{Binding outputDevicesInputChannelsVisible, ElementName=page}" Value="True" />
                                        <Condition Binding="{Binding outputDevicesOutputChannelsVisible, ElementName=page}" Value="False" />
                                    </MultiDataTrigger.Conditions>
                                    <MultiDataTrigger.Setters>
                                        <Setter Property="ItemsSource">
                                            <Setter.Value>
                                                <Binding Path="InputChannels"/>
                                            </Setter.Value>
                                        </Setter>
                                    </MultiDataTrigger.Setters>
                                </MultiDataTrigger>
                            </Style.Triggers>
                        </Style>
                    </ContextMenu.Style>
                    <!--<ContextMenu.ItemsSource>
                        <MultiBinding>
                            <MultiBinding.Converter>
                                <local:CompositeCollectionConverter/>
                            </MultiBinding.Converter>
                            <Binding Path="InputChannels"/>
                            <Binding Path="OutputChannels"/>
                        </MultiBinding>
                    </ContextMenu.ItemsSource>-->
                    <ContextMenu.ItemContainerStyle>
                        <Style TargetType="{x:Type MenuItem}">
                            <Setter Property="Template" Value="{StaticResource NoIconColumnMenuItem}">
                            </Setter>
                            <EventSetter Event="Click" Handler="ChannelClick"/>
                        </Style>
                    </ContextMenu.ItemContainerStyle>
                </ContextMenu>
            </Button.ContextMenu>
            <Grid>
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="Auto"/>
                    <ColumnDefinition Width="*"/>
                    <ColumnDefinition Width="Auto"/>
                </Grid.ColumnDefinitions>
                <Grid.RowDefinitions>
                    <RowDefinition Height="Auto"/>
                    <RowDefinition Height="Auto"/>
                </Grid.RowDefinitions>
                <Image Width="32" Height="32" Source="{Binding StatusIcon}" Grid.RowSpan="2" RenderOptions.BitmapScalingMode="HighQuality"/>
                <TextBlock Grid.Column="1" Text="{Binding DeviceName}" FontWeight="Bold" FontSize="13.333" Foreground="#FF0F0970"/>
                <TextBlock Grid.Column="1" Grid.Row="1" Text="{Binding}"/>
                <Button Grid.Column="2" Content="X" Visibility="{Binding isImplicitlyRemoveable, Converter={StaticResource BoolToVisibilityConverter}}" Click="RemoveDevice" HorizontalAlignment="Right" VerticalAlignment="Top" Background="#FFF08F8F" BorderBrush="#FFBD4848" Foreground="White" FontWeight="Bold" Padding="2,0"/>
            </Grid>
        </Button>
    </DataTemplate>

错误很明显：

  

System.Windows.Data错误：4：找不到绑定源   参考＆＃39; ElementName = page＆＃39;。   BindingExpression：路径= outputDevicesInputChannelsVisible;   的DataItem = NULL;目标元素是＆＃39; ContextMenu＆＃39; （名称=＆＃39;＆＃39）;目标   物业是NoCarget＆＃39; （键入＆＃39;对象＆＃39;）

这是因为ElementName无法从上下文菜单中爬行逻辑树或可视树。

我接近上下文菜单并重新设计它以使用普通菜单，但我想先给它一个裂缝。

根据以下评论修改。这几乎正​​常，但是遵循此格式<Condition Binding="{Binding Path=DataContext,Converter={StaticResource TypeOfConverter},RelativeSource={RelativeSource AncestorType={x:Type Button}}}" Value="{x:Type ODIF:OutputDevice}" />的条件绑定不起作用，需要检查按钮绑定数据

    <DataTemplate x:Key="ODIF.Device">
        <Button HorizontalContentAlignment="Stretch" Background="WhiteSmoke" Padding="10,1" ContextMenuService.Placement="Right" VerticalContentAlignment="Stretch" Tag="{Binding RelativeSource={RelativeSource AncestorType={x:Type Page}}}">
            <Button.BorderBrush>
                <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                    <GradientStop Color="#FFC9C9C9" Offset="1"/>
                    <GradientStop Color="WhiteSmoke" Offset="0"/>
                </LinearGradientBrush>
            </Button.BorderBrush>
            <i:Interaction.Behaviors>
                <local:DropDownButtonBehavior/>
            </i:Interaction.Behaviors>

            <Button.ContextMenu>
                <ContextMenu ItemTemplate="{StaticResource ODIF.Channel}" DataContext="{Binding Path=PlacementTarget.Tag, RelativeSource={RelativeSource Self}}">
                    <ContextMenu.Style>
                        <Style TargetType="ContextMenu">
                            <Style.Triggers>
                                <MultiDataTrigger>
                                    <MultiDataTrigger.Conditions>
                                        <Condition Binding="{Binding Path=DataContext,Converter={StaticResource TypeOfConverter},RelativeSource={RelativeSource AncestorType={x:Type Button}}}" Value="{x:Type ODIF:InputDevice}" />
                                        <Condition Binding="{Binding inputDevicesInputChannelsVisible}" Value="True" />
                                        <Condition Binding="{Binding inputDevicesOutputChannelsVisible}" Value="True" />
                                    </MultiDataTrigger.Conditions>
                                    <MultiDataTrigger.Setters>
                                        <Setter Property="ItemsSource">
                                            <Setter.Value>
                                                <MultiBinding>
                                                    <MultiBinding.Converter>
                                                        <local:CompositeCollectionConverter/>
                                                    </MultiBinding.Converter>
                                                    <Binding Path="DataContext.InputChannels" RelativeSource="{RelativeSource AncestorType={x:Type Button}}"/>
                                                    <Binding Path="DataContext.OutputChannels" RelativeSource="{RelativeSource AncestorType={x:Type Button}}"/>
                                                </MultiBinding>
                                            </Setter.Value>
                                        </Setter>
                                    </MultiDataTrigger.Setters>
                                </MultiDataTrigger>
                                <MultiDataTrigger>
                                    <MultiDataTrigger.Conditions>
                                        <Condition Binding="{Binding Path=DataContext,Converter={StaticResource TypeOfConverter},RelativeSource={RelativeSource AncestorType={x:Type Button}}}" Value="{x:Type ODIF:InputDevice}" />
                                        <Condition Binding="{Binding inputDevicesInputChannelsVisible}" Value="False" />
                                        <Condition Binding="{Binding inputDevicesOutputChannelsVisible}" Value="True" />
                                    </MultiDataTrigger.Conditions>
                                    <MultiDataTrigger.Setters>
                                        <Setter Property="ItemsSource">
                                            <Setter.Value>
                                                <Binding Path="DataContext.OutputChannels" RelativeSource="{RelativeSource AncestorType={x:Type Button}}"/>
                                            </Setter.Value>
                                        </Setter>
                                    </MultiDataTrigger.Setters>
                                </MultiDataTrigger>
                                <MultiDataTrigger>
                                    <MultiDataTrigger.Conditions>
                                        <Condition Binding="{Binding Path=DataContext,Converter={StaticResource TypeOfConverter},RelativeSource={RelativeSource AncestorType={x:Type Button}}}" Value="{x:Type ODIF:InputDevice}" />
                                        <Condition Binding="{Binding inputDevicesInputChannelsVisible}" Value="True" />
                                        <Condition Binding="{Binding inputDevicesOutputChannelsVisible}" Value="False" />
                                    </MultiDataTrigger.Conditions>
                                    <MultiDataTrigger.Setters>
                                        <Setter Property="ItemsSource">
                                            <Setter.Value>
                                                <Binding Path="DataContext.InputChannels" RelativeSource="{RelativeSource AncestorType={x:Type Button}}"/>
                                            </Setter.Value>
                                        </Setter>
                                    </MultiDataTrigger.Setters>
                                </MultiDataTrigger>

                                <MultiDataTrigger>
                                    <MultiDataTrigger.Conditions>
                                        <Condition Binding="{Binding Path=DataContext,Converter={StaticResource TypeOfConverter},RelativeSource={RelativeSource AncestorType={x:Type Button}}}" Value="{x:Type ODIF:OutputDevice}" />
                                        <Condition Binding="{Binding outputDevicesInputChannelsVisible}" Value="True" />
                                        <Condition Binding="{Binding outputDevicesOutputChannelsVisible}" Value="True" />
                                    </MultiDataTrigger.Conditions>
                                    <MultiDataTrigger.Setters>
                                        <Setter Property="ItemsSource">
                                            <Setter.Value>
                                                <MultiBinding>
                                                    <MultiBinding.Converter>
                                                        <local:CompositeCollectionConverter/>
                                                    </MultiBinding.Converter>
                                                    <Binding Path="DataContext.InputChannels" RelativeSource="{RelativeSource AncestorType={x:Type Button}}"/>
                                                    <Binding Path="DataContext.OutputChannels" RelativeSource="{RelativeSource AncestorType={x:Type Button}}"/>
                                                </MultiBinding>
                                            </Setter.Value>
                                        </Setter>
                                    </MultiDataTrigger.Setters>
                                </MultiDataTrigger>
                                <MultiDataTrigger>
                                    <MultiDataTrigger.Conditions>
                                        <Condition Binding="{Binding Path=DataContext,Converter={StaticResource TypeOfConverter},RelativeSource={RelativeSource AncestorType={x:Type Button}}}" Value="{x:Type ODIF:OutputDevice}" />
                                        <Condition Binding="{Binding outputDevicesInputChannelsVisible}" Value="False" />
                                        <Condition Binding="{Binding outputDevicesOutputChannelsVisible}" Value="True" />
                                    </MultiDataTrigger.Conditions>
                                    <MultiDataTrigger.Setters>
                                        <Setter Property="ItemsSource">
                                            <Setter.Value>
                                                <Binding Path="DataContext.OutputChannels" RelativeSource="{RelativeSource AncestorType={x:Type Button}}"/>
                                            </Setter.Value>
                                        </Setter>
                                    </MultiDataTrigger.Setters>
                                </MultiDataTrigger>
                                <MultiDataTrigger>
                                    <MultiDataTrigger.Conditions>
                                        <Condition Binding="{Binding Path=DataContext,Converter={StaticResource TypeOfConverter},RelativeSource={RelativeSource AncestorType={x:Type Button}}}" Value="{x:Type ODIF:OutputDevice}" />
                                        <Condition Binding="{Binding outputDevicesInputChannelsVisible}" Value="True" />
                                        <Condition Binding="{Binding outputDevicesOutputChannelsVisible}" Value="False" />
                                    </MultiDataTrigger.Conditions>
                                    <MultiDataTrigger.Setters>
                                        <Setter Property="ItemsSource">
                                            <Setter.Value>
                                                <Binding Path="DataContext.InputChannels" RelativeSource="{RelativeSource AncestorType={x:Type Button}}"/>
                                            </Setter.Value>
                                        </Setter>
                                    </MultiDataTrigger.Setters>
                                </MultiDataTrigger>
                            </Style.Triggers>
                        </Style>
                    </ContextMenu.Style>
                    <!--<ContextMenu.ItemsSource>
                        <MultiBinding>
                            <MultiBinding.Converter>
                                <local:CompositeCollectionConverter/>
                            </MultiBinding.Converter>
                            <Binding Path="InputChannels"/>
                            <Binding Path="OutputChannels"/>
                        </MultiBinding>
                    </ContextMenu.ItemsSource>-->
                    <ContextMenu.ItemContainerStyle>
                        <Style TargetType="{x:Type MenuItem}">
                            <Setter Property="Template" Value="{StaticResource NoIconColumnMenuItem}">
                            </Setter>
                            <EventSetter Event="Click" Handler="ChannelClick"/>
                        </Style>
                    </ContextMenu.ItemContainerStyle>
                </ContextMenu>
            </Button.ContextMenu>
            <Grid>
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="Auto"/>
                    <ColumnDefinition Width="*"/>
                    <ColumnDefinition Width="Auto"/>
                </Grid.ColumnDefinitions>
                <Grid.RowDefinitions>
                    <RowDefinition Height="Auto"/>
                    <RowDefinition Height="Auto"/>
                </Grid.RowDefinitions>
                <Image Width="32" Height="32" Source="{Binding StatusIcon}" Grid.RowSpan="2" RenderOptions.BitmapScalingMode="HighQuality"/>
                <TextBlock Grid.Column="1" Text="{Binding DeviceName}" FontWeight="Bold" FontSize="13.333" Foreground="#FF0F0970"/>
                <TextBlock Grid.Column="1" Grid.Row="1" Text="{Binding}"/>
                <Button Grid.Column="2" Content="X" Visibility="{Binding isImplicitlyRemoveable, Converter={StaticResource BoolToVisibilityConverter}}" Click="RemoveDevice" HorizontalAlignment="Right" VerticalAlignment="Top" Background="#FFF08F8F" BorderBrush="#FFBD4848" Foreground="White" FontWeight="Bold" Padding="2,0"/>
            </Grid>
        </Button>
    </DataTemplate>