Question

我在视图模型中找到了几个绑定IsSelected属性的示例。但是，这些都不涉及具有分层数据模板的TreeView。

My Hierachy就像这样

VM_Part
- VM_Step
- VM_Step
- VM_Step
VM_Part
- VM_Step
- VM_Step

我希望能够在一个部件下选择多个VM_Part实例或多个VM_Steps。我的想法是，我可以拥有一个上下文菜单，并对所选项目执行各种命令

<Window x:Class="NameSpace1.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:local="clr-namespace:Hipot_Sequence_Editor"
    xmlns:xctk="http://schemas.xceed.com/wpf/xaml/toolkit"

    mc:Ignorable="d"
    Title="MainWindow" Height="677.538" Width="896.456">

<Window.DataContext>
    <local:VM_Main></local:VM_Main>
</Window.DataContext>
<Grid>
    <TreeView x:Name="treeView" Grid.Column="1" HorizontalAlignment="Left" Height="628" Margin="10.2,10,0,0" VerticalAlignment="Top" Width="237" Grid.RowSpan="2" ItemsSource="{Binding Parts}">
        <TreeView.Resources>
            <HierarchicalDataTemplate DataType="{x:Type viewModels:VM_Part}" ItemsSource="{Binding VM_Steps}">
                <StackPanel Orientation="Horizontal">
                    <TextBlock Text="{Binding SequenceNumber}" />
                    <TextBlock Text=" - "></TextBlock>
                    <TextBlock Text="{Binding PartNumber}" />
                </StackPanel>
            </HierarchicalDataTemplate>
            <DataTemplate DataType="{x:Type viewModels:VM_Step}">
                <StackPanel Orientation="Horizontal">
                    <TextBlock Text="{Binding Name}" />
                </StackPanel>
            </DataTemplate>
        </TreeView.Resources>
    </TreeView>
</Grid>

This在我看来是我需要的壁橱示例。我尝试了第一个回答建议

<TreeView.Resources>
    <Style TargetType="TreeViewItem">
        <Setter Property="IsSelected"
                Value="{Binding Path=IsSelected, Mode=TwoWay}" />
    </Style>
</TreeView.Resources>

但是，此代码似乎假设IsSelected位于VM_Main而不是VM_Part或VM_Step

Answer 1

层次结构中的每个TreeViewItem

VM_Part TreeViewItem
- VM_Step TreeViewItem
- VM_Step TreeViewItem
- VM_Step TreeViewItem

有自己的DataContext（VM_Part或VM_Step）

因此，如果VM_Part和VM_Step具有IsSelected属性，则正确定义TreeViewItem的样式

<Style TargetType="TreeViewItem">
    <Setter Property="IsSelected"
            Value="{Binding Path=IsSelected, Mode=TwoWay}" />
</Style>

然而，TreeView中的多选可能更简单，CheckBoxes添加到项模板并绑定到视图模型IsSelected属性：

<HierarchicalDataTemplate DataType="{x:Type viewModels:VM_Part}" ItemsSource="{Binding VM_Steps}">
    <StackPanel Orientation="Horizontal">
        <CheckBox IsChecked="{Binding IsSelected, UpdateSourceTrigger=PropertyChanged}" />
        <TextBlock Text="{Binding SequenceNumber}" />
        <TextBlock Text=" - "/>
        <TextBlock Text="{Binding PartNumber}" />
    </StackPanel>
</HierarchicalDataTemplate>
<DataTemplate DataType="{x:Type viewModels:VM_Step}">
    <StackPanel Orientation="Horizontal">
        <CheckBox IsChecked="{Binding IsSelected, UpdateSourceTrigger=PropertyChanged}" />
        <TextBlock Text="{Binding Name}" />
    </StackPanel>
</DataTemplate>

使用分层数据模板选择树视图

1 个答案: