Question

当我单击树上的按钮时，我只想在树视图中标识选定的节点，请考虑下图：

Treeview绑定到viewmodel，当单击加号按钮时，我有一个属性可保存该值，应设置所选节点的值。在单击加号按钮之前，首先单击“样本节点”时才设置所选值。下面是我的xaml的代码：

<TreeView x:Name="tree" ItemsSource="{Binding SectorTree, Mode=OneWay}" MinHeight="150">
    <TreeView.ItemTemplate>
        <HierarchicalDataTemplate ItemsSource="{Binding Children, Mode=OneTime}">
            <StackPanel Orientation="Horizontal">
                <Button HorizontalAlignment="Center" Command="{Binding SelectedItemChangedCommand, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
                                            ToolTip="Edit sector name" Background="Transparent" BorderThickness="0">
                    <Button.Content>
                        <Image Width="14" Height="14" Margin="0,0,0,0" Source="path_of_image" />
                    </Button.Content>
                </Button>
                <ContentPresenter Content="{Binding SectorName, Mode=OneTime}" Margin="2,0" />
            </StackPanel>
        </HierarchicalDataTemplate>
    </TreeView.ItemTemplate>
    <TreeView.ItemContainerStyle>
        <Style TargetType="{x:Type TreeViewItem}">
            <Setter Property="IsSelected" Value="{Binding IsSelected,  Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />
        </Style>
    </TreeView.ItemContainerStyle>
</TreeView>

Answer 1

这是我解决TreeView中按钮的Click事件中的相同问题的方法。

向绑定到每个TreeView节点的MyNodeClass添加“ Me”属性：
```
public object Me { get { return this; } }
```

将Button的Tag属性绑定给我：

Button Tag="{Binding Me}" Click="Button_Click"

在Button_Click（对象发送方...）事件中查找实例：
```
MyNodeClass x = ((Button)sender).Tag as MyNodeClass
```

Answer 2

目前尚不清楚您要通过将此按钮添加到TreeView数据模板来解决什么问题。

TreeView已经具有一个SelectedItemChanged事件和一个SelectedItem属性。

替代方法是使用Behavior向Treeiew添加新的可绑定BoundSelectedItem属性。这将返回数据项类，而不是TreeViewItem实例。

public class perTreeViewHelper : Behavior<TreeView>
{
    public object BoundSelectedItem
    {
        get => GetValue(BoundSelectedItemProperty);
        set => SetValue(BoundSelectedItemProperty, value);
    }

    public static readonly DependencyProperty BoundSelectedItemProperty =
        DependencyProperty.Register("BoundSelectedItem",
            typeof(object),
            typeof(perTreeViewHelper),
            new FrameworkPropertyMetadata(null,
                FrameworkPropertyMetadataOptions.BindsTwoWayByDefault,
                OnBoundSelectedItemChanged));

    private static void OnBoundSelectedItemChanged(DependencyObject obj, DependencyPropertyChangedEventArgs args)
    {
        if (args.NewValue is perTreeViewItemViewModelBase item)
            item.IsSelected = true;
    }

    protected override void OnAttached()
    {
        base.OnAttached();
        AssociatedObject.SelectedItemChanged += OnTreeViewSelectedItemChanged;
    }

    protected override void OnDetaching()
    {
        AssociatedObject.SelectedItemChanged -= OnTreeViewSelectedItemChanged;
        base.OnDetaching();
    }

    private void OnTreeViewSelectedItemChanged(object obj, RoutedPropertyChangedEventArgs<object> args)
    {
        BoundSelectedItem = args.NewValue;
    }
}

有关我最近的blog post的更多详细信息。

C＃wpf mvvm通过单击按钮

2 个答案: