在TreeView中更改展开项的位置

时间：2016-10-19 15:19:00

标签： c# wpf treeview

标准WPF树视图在父项下面展开时显示子项。为了获得更好的可见性，我想在父级右侧显示子项。像这样：

The *Release* items are children of *ReleaseLists*

发布项是发布列表

的子项

（怎么样）我可以实现这个目标吗？

提前致谢，
弗兰克

1 个答案:

答案 0 :(得分：0)

您无法从其TreeViewItem中取出TreeView。您可以做的最好是修改其模板以水平扩展它。但是，你也不会达到预期的效果，因为扩展区域不会像Popup那样浮动。

因此，我创建了一个源自Control的新Menu。 Menu最适合您的情况，因为它会水平打开其子菜单。从不离屏。需要新的Control来覆盖其在mouse-over上打开子菜单的行为。我们需要TreeView类似行为，因此必须在mouse-click上进行扩展，而不是在悬停时进行扩展。

此控件还可以保留全键盘支持，以使用Menu键导航整个left/right/up/down/esc。

在您的窗口中删除菜单控件，然后右键单击Menu中的Document Outline > Edit Additional Templates > ItemContainerStyle控件。这将为您提供所需的资源。只需复制将其原样粘贴到名为TreeViewFloatingDisplay.xaml的新文件中，如下所示。我已经省略了...的简洁代码，替换后的内容会显示注释，新内容会显示在其下方。

TreeViewFloatingDisplay.xaml 

<Menu x:Class="WpfStackOverflow.MenuAsTreeView2.TreeViewFloatingDisplay"
         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
         xmlns:Themes="clr-namespace:Microsoft.Windows.Themes;assembly=PresentationFramework.Aero"
         mc:Ignorable="d" 
         d:DesignHeight="300" d:DesignWidth="300">

<Menu.Resources>
    <Geometry x:Key="RightArrow">M 0,0 L 4,3.5 L 0,7 Z</Geometry>
    <LinearGradientBrush x:Key="MenuItemSelectionFill" EndPoint="0,1" StartPoint="0,0">
        <GradientStop Color="#34C5EBFF" Offset="0"/>
        <GradientStop Color="#3481D8FF" Offset="1"/>
    </LinearGradientBrush>
    <Geometry x:Key="Checkmark">M 0,5.1 L 1.7,5.2 L 3.4,7.1 L 8,0.4 L 9.2,0 L 3.3,10.8 Z</Geometry>
    <ControlTemplate x:Key="{ComponentResourceKey ResourceId=SubmenuItemTemplateKey, TypeInTargetAssembly={x:Type MenuItem}}" TargetType="{x:Type MenuItem}">
        <Grid SnapsToDevicePixels="true">
            <Rectangle x:Name="Bg" Fill="{TemplateBinding Background}" RadiusY="2" RadiusX="2" Stroke="{TemplateBinding BorderBrush}" StrokeThickness="1"/>
            <Rectangle x:Name="InnerBorder" Margin="1" RadiusY="2" RadiusX="2"/>
            <Grid>
                <Grid.ColumnDefinitions>
                    <ColumnDefinition MinWidth="14" SharedSizeGroup="MenuItemIconColumnGroup" Width="Auto"/>
                    <ColumnDefinition Width="4"/>
                    <ColumnDefinition Width="*"/>
                    <!--<ColumnDefinition Width="37"/>-->
                    <ColumnDefinition Width="0"/>
                    <ColumnDefinition SharedSizeGroup="MenuItemIGTColumnGroup" Width="Auto"/>
                    <!--<ColumnDefinition Width="17"/>-->
                    <ColumnDefinition Width="0"/>
                </Grid.ColumnDefinitions>
                <ContentPresenter x:Name="Icon" ContentSource="Icon" Margin="1" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="Center"/>
                <Border x:Name="GlyphPanel" BorderBrush="#CDD3E6" BorderThickness="1" Background="#E6EFF4" CornerRadius="3" Height="22" Margin="1" Visibility="Hidden" Width="22">
                    <Path x:Name="Glyph" Data="{StaticResource Checkmark}" Fill="#0C12A1" FlowDirection="LeftToRight" Height="11" Width="9"/>
                </Border>
                <ContentPresenter Grid.Column="2" ContentSource="Header" Margin="{TemplateBinding Padding}" RecognizesAccessKey="True" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
                <TextBlock Grid.Column="4" Margin="{TemplateBinding Padding}" Text="{TemplateBinding InputGestureText}"/>
            </Grid>
        </Grid>
        <ControlTemplate.Triggers>
            ...
        </ControlTemplate.Triggers>
    </ControlTemplate>
    <LinearGradientBrush x:Key="MenuItemPressedFill" EndPoint="0,1" StartPoint="0,0">
        ...
    </LinearGradientBrush>
    <SolidColorBrush x:Key="SubMenuBackgroundBrush" Color="#FFF5F5F5"/>
    <Geometry x:Key="UpArrow">M 0,4 L 3.5,0 L 7,4 Z</Geometry>
    <Style x:Key="MenuScrollButton" BasedOn="{x:Null}" TargetType="{x:Type RepeatButton}">
        ...
    </Style>
    <MenuScrollingVisibilityConverter x:Key="MenuScrollingVisibilityConverter"/>
    <Geometry x:Key="DownArrow">M 0,0 L 3.5,4 L 7,0 Z</Geometry>
    <Style x:Key="{ComponentResourceKey ResourceId=MenuScrollViewer, TypeInTargetAssembly={x:Type FrameworkElement}}" BasedOn="{x:Null}" TargetType="{x:Type ScrollViewer}">
        ...
    </Style>
    <ControlTemplate x:Key="{ComponentResourceKey ResourceId=TopLevelHeaderTemplateKey, TypeInTargetAssembly={x:Type MenuItem}}" TargetType="{x:Type MenuItem}">
        <Grid SnapsToDevicePixels="true">
            <Rectangle x:Name="OuterBorder" RadiusY="2" RadiusX="2"/>
            <Rectangle x:Name="Bg" Fill="{TemplateBinding Background}" Margin="1" RadiusY="1" RadiusX="1" Stroke="{TemplateBinding BorderBrush}" StrokeThickness="1"/>
            <Rectangle x:Name="InnerBorder" Margin="2"/>
            <DockPanel>
                <Path x:Name="PART_RightArrow" Data="{StaticResource RightArrow}" Fill="Transparent" Stroke="Black" Margin="8,0,0,0" VerticalAlignment="Center" HorizontalAlignment="Right"/>
                <ContentPresenter Visibility="Collapsed" x:Name="Icon" ContentSource="Icon" Margin="4,0,6,0" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="Center"/>
                <Path x:Name="GlyphPanel" Data="{StaticResource Checkmark}" Fill="{TemplateBinding Foreground}" FlowDirection="LeftToRight" Margin="7,0,0,0" Visibility="Collapsed" VerticalAlignment="Center"/>
                <ContentPresenter ContentSource="Header" Margin="{TemplateBinding Padding}" RecognizesAccessKey="True" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
            </DockPanel>
            <!--<Popup x:Name="PART_Popup" AllowsTransparency="true" Focusable="false" HorizontalOffset="1" IsOpen="{Binding IsSubmenuOpen, RelativeSource={RelativeSource TemplatedParent}}" PopupAnimation="{DynamicResource {x:Static SystemParameters.MenuPopupAnimationKey}}" Placement="Bottom" VerticalOffset="-1">-->
            <Popup x:Name="PART_Popup" AllowsTransparency="true" Focusable="false" HorizontalOffset="1" IsOpen="{Binding IsSubmenuOpen, RelativeSource={RelativeSource TemplatedParent}}" PopupAnimation="{DynamicResource {x:Static SystemParameters.MenuPopupAnimationKey}}" Placement="Right" VerticalOffset="0">
                <Themes:SystemDropShadowChrome x:Name="Shdw" Color="Transparent">
                    <Border x:Name="SubMenuBorder" BorderBrush="#FF959595" BorderThickness="1" Background="{StaticResource SubMenuBackgroundBrush}">
                        <ScrollViewer x:Name="SubMenuScrollViewer" Margin="1,0" Style="{DynamicResource {ComponentResourceKey ResourceId=MenuScrollViewer, TypeInTargetAssembly={x:Type FrameworkElement}}}">
                            <Grid RenderOptions.ClearTypeHint="Enabled">
                                <Canvas HorizontalAlignment="Left" Height="0" VerticalAlignment="Top" Width="0">
                                    <Rectangle x:Name="OpaqueRect" Fill="{StaticResource SubMenuBackgroundBrush}" Height="{Binding ActualHeight, ElementName=SubMenuBorder}" Width="{Binding ActualWidth, ElementName=SubMenuBorder}"/>
                                </Canvas>
                                <!-- Comment below 3 rectangles to remove vertical line present on the left -->
                                <!--<Rectangle Fill="#F1F1F1" HorizontalAlignment="Left" Margin="1,2" RadiusY="2" RadiusX="2" Width="28"/>
                                <Rectangle Fill="#E2E3E3" HorizontalAlignment="Left" Margin="29,2,0,2" Width="1"/>
                                <Rectangle Fill="White" HorizontalAlignment="Left" Margin="30,2,0,2" Width="1"/>-->
                                <ItemsPresenter x:Name="ItemsPresenter" KeyboardNavigation.DirectionalNavigation="Cycle" Grid.IsSharedSizeScope="true" Margin="2" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" KeyboardNavigation.TabNavigation="Cycle"/>
                            </Grid>
                        </ScrollViewer>
                    </Border>
                </Themes:SystemDropShadowChrome>
            </Popup>
        </Grid>
        <ControlTemplate.Triggers>
            ...
        </ControlTemplate.Triggers>
    </ControlTemplate>
    <ControlTemplate x:Key="{ComponentResourceKey ResourceId=TopLevelItemTemplateKey, TypeInTargetAssembly={x:Type MenuItem}}" TargetType="{x:Type MenuItem}">
        ...
    </ControlTemplate>

    <ControlTemplate x:Key="{ComponentResourceKey ResourceId=SubmenuHeaderTemplateKey, TypeInTargetAssembly={x:Type MenuItem}}" TargetType="{x:Type MenuItem}">
        <Grid SnapsToDevicePixels="true">
            <Rectangle x:Name="Bg" Fill="{TemplateBinding Background}" RadiusY="2" RadiusX="2" Stroke="{TemplateBinding BorderBrush}" StrokeThickness="1"/>
            <Rectangle x:Name="InnerBorder" Margin="1" RadiusY="2" RadiusX="2" Stroke="Transparent" StrokeThickness="1"/>
            <Grid>
                <Grid.ColumnDefinitions>
                    <ColumnDefinition MinWidth="14" SharedSizeGroup="MenuItemIconColumnGroup" Width="Auto"/>
                    <ColumnDefinition Width="4"/>
                    <ColumnDefinition Width="*"/>
                    <!--<ColumnDefinition Width="37"/>-->
                    <ColumnDefinition Width="0"/>
                    <ColumnDefinition SharedSizeGroup="MenuItemIGTColumnGroup" Width="Auto"/>
                    <!--<ColumnDefinition Width="17"/>-->
                    <ColumnDefinition Width="0"/>
                </Grid.ColumnDefinitions>
                <ContentPresenter x:Name="Icon" ContentSource="Icon" Margin="1" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="Center"/>
                <Border x:Name="GlyphPanel" BorderBrush="#CDD3E6" BorderThickness="1" Background="#E6EFF4" CornerRadius="3" Height="22" Margin="1" Visibility="Hidden" Width="22">
                    <Path x:Name="Glyph" Data="{StaticResource Checkmark}" Fill="#0C12A1" FlowDirection="LeftToRight" Height="11" Width="9"/>
                </Border>
                <ContentPresenter Grid.Column="2" ContentSource="Header" Margin="{TemplateBinding Padding}" RecognizesAccessKey="True" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
                <TextBlock Grid.Column="4" Margin="{TemplateBinding Padding}" Text="{TemplateBinding InputGestureText}" Visibility="Collapsed"/>
                <!--<Path Grid.Column="5" Data="{StaticResource RightArrow}" Fill="{TemplateBinding Foreground}" Margin="4,0,0,0" VerticalAlignment="Center"/>-->
                <Path Grid.Column="0" x:Name="PART_RightArrow" Data="{StaticResource RightArrow}" Fill="Transparent" Stroke="Black" Margin="4,0,0,0" VerticalAlignment="Center" HorizontalAlignment="Center"/>
            </Grid>

            <!--<Popup x:Name="PART_Popup" AllowsTransparency="true" Focusable="false" HorizontalOffset="-2" IsOpen="{Binding IsSubmenuOpen, RelativeSource={RelativeSource TemplatedParent}}" PopupAnimation="{DynamicResource {x:Static SystemParameters.MenuPopupAnimationKey}}" Placement="Right" VerticalOffset="-3">-->
            <Popup x:Name="PART_Popup" AllowsTransparency="true" Focusable="false" HorizontalOffset="3" IsOpen="{Binding IsSubmenuOpen, RelativeSource={RelativeSource TemplatedParent}}" PopupAnimation="{DynamicResource {x:Static SystemParameters.MenuPopupAnimationKey}}" Placement="Right" VerticalOffset="-4">
                <Themes:SystemDropShadowChrome x:Name="Shdw" Color="Transparent">
                    <Border x:Name="SubMenuBorder" BorderBrush="#FF959595" BorderThickness="1" Background="{StaticResource SubMenuBackgroundBrush}">
                        <ScrollViewer x:Name="SubMenuScrollViewer" Margin="1,0" Style="{DynamicResource {ComponentResourceKey ResourceId=MenuScrollViewer, TypeInTargetAssembly={x:Type FrameworkElement}}}">
                            <Grid RenderOptions.ClearTypeHint="Enabled">
                                <Canvas HorizontalAlignment="Left" Height="0" VerticalAlignment="Top" Width="0">
                                    <Rectangle x:Name="OpaqueRect" Fill="{StaticResource SubMenuBackgroundBrush}" Height="{Binding ActualHeight, ElementName=SubMenuBorder}" Width="{Binding ActualWidth, ElementName=SubMenuBorder}"/>
                                </Canvas>
                                <!-- Comment below 3 rectangles to remove vertical line present on the left -->
                                <!--<Rectangle Fill="#F1F1F1" HorizontalAlignment="Left" Margin="1,2" RadiusY="2" RadiusX="2" Width="28"/>
                                <Rectangle Fill="#E2E3E3" HorizontalAlignment="Left" Margin="29,2,0,2" Width="1"/>
                                <Rectangle Fill="White" HorizontalAlignment="Left" Margin="30,2,0,2" Width="1"/>-->
                                <ItemsPresenter x:Name="ItemsPresenter" KeyboardNavigation.DirectionalNavigation="Cycle" Grid.IsSharedSizeScope="true" Margin="2" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" KeyboardNavigation.TabNavigation="Cycle"/>
                            </Grid>
                        </ScrollViewer>
                    </Border>
                </Themes:SystemDropShadowChrome>
            </Popup>
        </Grid>
        <ControlTemplate.Triggers>
            ...
        </ControlTemplate.Triggers>
    </ControlTemplate>
    <Style x:Key="MenuItemStyle1" TargetType="{x:Type MenuItem}">
        <Setter Property="HorizontalContentAlignment" Value="{Binding HorizontalContentAlignment, RelativeSource={RelativeSource AncestorType={x:Type ItemsControl}}}"/>
        <Setter Property="VerticalContentAlignment" Value="{Binding VerticalContentAlignment, RelativeSource={RelativeSource AncestorType={x:Type ItemsControl}}}"/>
        <Setter Property="Background" Value="Transparent"/>
        <Setter Property="ScrollViewer.PanningMode" Value="Both"/>
        <Setter Property="Stylus.IsFlicksEnabled" Value="False"/>
        <Setter Property="Template" Value="{DynamicResource {ComponentResourceKey ResourceId=SubmenuItemTemplateKey, TypeInTargetAssembly={x:Type MenuItem}}}"/>
        <Style.Triggers>
            <Trigger Property="Role" Value="TopLevelHeader">
                <Setter Property="Padding" Value="7,2,8,3"/>
                <Setter Property="Template" Value="{DynamicResource {ComponentResourceKey ResourceId=TopLevelHeaderTemplateKey, TypeInTargetAssembly={x:Type MenuItem}}}"/>
            </Trigger>
            <Trigger Property="Role" Value="TopLevelItem">
                <Setter Property="Padding" Value="7,2,8,3"/>
                <Setter Property="Template" Value="{DynamicResource {ComponentResourceKey ResourceId=TopLevelItemTemplateKey, TypeInTargetAssembly={x:Type MenuItem}}}"/>
            </Trigger>
            <Trigger Property="Role" Value="SubmenuHeader">
                <!--<Setter Property="Padding" Value="2,3,2,3"/>-->
                <Setter Property="Padding" Value="1,2,1,2"/>
                <Setter Property="Template" Value="{DynamicResource {ComponentResourceKey ResourceId=SubmenuHeaderTemplateKey, TypeInTargetAssembly={x:Type MenuItem}}}"/>
            </Trigger>
            <Trigger Property="Role" Value="SubmenuItem">
                <!--<Setter Property="Padding" Value="2,3,2,3"/>-->
                <Setter Property="Padding" Value="1,2,1,2"/>
            </Trigger>
        </Style.Triggers>
    </Style>
</Menu.Resources>

</Menu>

TreeViewFloatingDisplay.xaml.cs 

using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Shapes;
using System.Windows.Threading;

namespace WpfStackOverflow.MenuAsTreeView2
{
    /// <summary>
    /// Interaction logic for TreeViewFloatingDisplay.xaml
    /// </summary>
    public partial class TreeViewFloatingDisplay : Menu
    {
        public TreeViewFloatingDisplay()
        {
            InitializeComponent();
        }

        protected override DependencyObject GetContainerForItemOverride()
        {
            return new MenuItemNew();
        }
    }

    public class MenuItemNew : MenuItem
    {
        #region Constructors
        static MenuItemNew()
        {
            MenuItem.IsSubmenuOpenProperty.OverrideMetadata(typeof(MenuItemNew),
                new FrameworkPropertyMetadata(false, MenuItem.IsSubmenuOpenProperty.DefaultMetadata.PropertyChangedCallback, CoerceIsSubmenuOpen));           
        }      

        public MenuItemNew()
        {
            this.PreviewMouseLeftButtonDown += MenuItemNew_PreviewMouseLeftButtonDown;
        }
        #endregion

        #region Event Handlers

        void MenuItemNew_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
        {
            MenuItemNew curItem = sender as MenuItemNew;
            System.Diagnostics.Debug.WriteLine("Role = " + curItem.Role);

            Path pth = e.OriginalSource as Path;
            if (pth == null) return;

            DependencyObject parent = VisualTreeHelper.GetParent(pth);
            while (parent as MenuItemNew == null)
                parent = VisualTreeHelper.GetParent(parent);

            MenuItemNew actualSource = parent as MenuItemNew;

            if (actualSource.Role == MenuItemRole.TopLevelHeader)
            {
                IsExpanderClicked = !IsExpanderClicked;
                actualSource.CoerceValue(MenuItemNew.IsSubmenuOpenProperty);
            }

            if (curItem.Role == MenuItemRole.SubmenuHeader)
            {
                IsExpanderClicked = !IsExpanderClicked;
                curItem.CoerceValue(MenuItemNew.IsSubmenuOpenProperty);
            }
        }

        #endregion

        #region IsExpanderClicked Dependency Property

        public bool IsExpanderClicked
        {
            get { return (bool)GetValue(IsExpanderClickedProperty); }
            set { SetValue(IsExpanderClickedProperty, value); }
        }

        // Using a DependencyProperty as the backing store for IsExpanderClicked.  This enables animation, styling, binding, etc...
        public static readonly DependencyProperty IsExpanderClickedProperty =
            DependencyProperty.Register("IsExpanderClicked", typeof(bool), typeof(MenuItemNew), new PropertyMetadata(false));

        #endregion

        #region Overrides
        protected override DependencyObject GetContainerForItemOverride()
        {
            return new MenuItemNew();
        }
        #endregion

        #region Dependency Property Callbacks
        private static object CoerceIsSubmenuOpen(DependencyObject d, object value)
        {
            MenuItemNew item = (MenuItemNew)d;

            if ((bool)value)
            {
                if (item.IsMouseOver)
                {
                    System.Diagnostics.Debug.WriteLine(item.IsExpanderClicked.ToString());
                    return item.IsExpanderClicked;
                }

                if (!item.IsLoaded)
                {
                    item.Loaded += (s, e) =>
                    {
                        Application.Current.Dispatcher.BeginInvoke(DispatcherPriority.Input, new DispatcherOperationCallback(delegate(object param)
                        {
                            item.CoerceValue(MenuItemNew.IsSubmenuOpenProperty);
                            return null;
                        }), null);
                    };
                    return false;
                }
            }
            if (item.IsExpanderClicked)
                return true;

            return value;
        }
        #endregion
    }
}

用法的

<Grid>

    <myMenu:TreeViewFloatingDisplay Background="AliceBlue" ItemsSource="{Binding Countries}" Width="300" HorizontalAlignment="Left">
        <myMenu:TreeViewFloatingDisplay.ItemsPanel>
            <ItemsPanelTemplate>
                <StackPanel/>
            </ItemsPanelTemplate>
        </myMenu:TreeViewFloatingDisplay.ItemsPanel>
        <myMenu:TreeViewFloatingDisplay.ItemTemplate>
            <HierarchicalDataTemplate ItemsSource="{Binding States}">
                <HierarchicalDataTemplate.ItemTemplate>
                    <HierarchicalDataTemplate ItemsSource="{Binding Cities}">                            
                        <Grid>
                            <ContentControl Content="{Binding .}">
                                <ContentControl.ContentTemplate>
                                    <DataTemplate>
                                        <Grid Background="#FFE8E8E8" HorizontalAlignment="Stretch" MinHeight="35">
                                            <Grid.ColumnDefinitions>
                                                <ColumnDefinition MinWidth="75"/>
                                                <ColumnDefinition MinWidth="150"/>
                                                <ColumnDefinition MinWidth="30"/>
                                            </Grid.ColumnDefinitions>
                                            <TextBlock Margin="3 1 1 1" Text="{Binding Name}" HorizontalAlignment="Left" VerticalAlignment="Center"/>
                                            <TextBox Grid.Column="1" Margin="1" VerticalAlignment="Center" HorizontalAlignment="Stretch" />
                                            <Label Grid.Column="2" Margin="1" VerticalAlignment="Center">
                                                <CheckBox />
                                            </Label>
                                        </Grid>
                                    </DataTemplate>
                                </ContentControl.ContentTemplate>
                            </ContentControl>
                        </Grid>
                    </HierarchicalDataTemplate>
                </HierarchicalDataTemplate.ItemTemplate>
                <ContentControl Content="{Binding .}">
                    <ContentControl.ContentTemplate>
                        <DataTemplate>
                            <Grid Background="#FFE8E8E8" HorizontalAlignment="Stretch" Width="255" MinHeight="35">
                                <Grid.ColumnDefinitions>
                                    <ColumnDefinition Width="75"/>
                                    <ColumnDefinition Width="150"/>
                                    <ColumnDefinition Width="30"/>
                                </Grid.ColumnDefinitions>
                                <TextBlock Margin="1" Text="{Binding Name}" HorizontalAlignment="Left" VerticalAlignment="Center"/>
                                <TextBox Grid.Column="1" Margin="1" VerticalAlignment="Center" HorizontalAlignment="Stretch" />
                                <Label Grid.Column="2" Margin="1" VerticalAlignment="Center">
                                    <CheckBox />
                                </Label>
                            </Grid>
                        </DataTemplate>
                    </ContentControl.ContentTemplate>
                </ContentControl>
            </HierarchicalDataTemplate>
        </myMenu:TreeViewFloatingDisplay.ItemTemplate>
    </myMenu:TreeViewFloatingDisplay>
</Grid>

ViewModel.cs 

public class ViewModel
    {
        public ObservableCollection<Country> Countries { get; set; }

        public ViewModel()
        {
            Countries = new ObservableCollection<Country>();
            Countries.Add(new Country()
            {
                Name = "India",
                States = new ObservableCollection<State>() 
                { new State()
                    { 
                        Name="MP",
                        Cities = new ObservableCollection<City>()
                        {
                            new City(){Name = "Bhopal"},new City(){Name = "Indore"}, new City(){Name = "Ujjain"}
                        }
                    } ,
                    new State()
                    { 
                        Name="UP",
                        Cities = new ObservableCollection<City>()
                        {
                            new City(){Name = "Agra"},new City(){Name = "Noida"}, new City(){Name = "Jhansi"}
                        }
                    } ,
                    new State()
                    { 
                        Name="AP",
                        Cities = new ObservableCollection<City>()
                        {
                            new City(){Name = "Hyderabad"},new City(){Name = "Warangal"}, new City(){Name = "Vijaywada"}
                        }
                    } 
                }
            });
            Countries.Add(new Country()
            {
                Name = "Australia",
                States = new ObservableCollection<State>() 
                { new State()
                    { 
                        Name="Tasmania",
                        Cities = new ObservableCollection<City>()
                        {
                            new City(){Name = "Sydney"},new City(){Name = "Melbourne"}
                        }
                    } 
                }
            });
        }


    }

    public class Country
    {
        public string Name { get; set; }
        public ObservableCollection<State> States { get; set; }
    }

    public class State
    {
        public string Name { get; set; }
        public ObservableCollection<City> Cities { get; set; }
    }

    public class City
    {
        public string Name { get; set; }
    }
相关问题
最新问题