在web开发中，带checkbox的tree是一个很有用的东东，比如权限选择、分类管理，如果不用sl，单纯用js+css实现是很复杂的，有了SL之后，就变得很轻松了
解决方案一：
利用Silvelright ToolKit(微软的开源项目)，项目地址http://silverlight.codeplex.com/
在线演示地址:http://silverlight.net/content/samples/sl4/toolkitcontrolsamples/run/default.html
解决方案二：
telerik公司的Rad for Silverlight商业控件(收费控件)
不管用哪一种方案，代码都是差不多的，为了实现数据绑定，先创建一个silverlight类库项目BusinessObject，定义数据项实体:
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Windows.Markup;
namespace BusinessObject
{
/// <summary>
/// 地区数据项
/// </summary>
[ContentProperty("Children")]//指示Children属性是 XAML 的Content内容属性
public class PlaceItem : INotifyPropertyChanged
{
/// <summary>
/// 构造函数
/// </summary>
public PlaceItem()
{
Children = new Collection<PlaceItem>();
IsSelected = true;
}
/// <summary>
/// 地区名称
/// </summary>
public string Name { get; set; }
/// <summary>
/// 地区描述
/// </summary>
public string Description { get; set; }
/// <summary>
/// 得到下级元素容器
/// </summary>
public Collection<PlaceItem> Children { get; private set; }
/// <summary>
/// 是否有子项
/// </summary>
public bool HasChild
{
get
{
return Children.Count > 0;
}
}
/// <summary>
/// 是否选中
/// </summary>
private bool? _isSelected;
/// <summary>
/// 该特性是否想要被安装
/// </summary>
public bool? IsSelected
{
get
{
return _isSelected;
}
set
{
if (value != _isSelected)
{
_isSelected = value;
OnPropertyChanged("IsSelected");
}
}
}
public event PropertyChangedEventHandler PropertyChanged;
/// <summary>
/// 属性改变时触发事件
/// </summary>
/// <param name="propertyName">Property that changed.</param>
private void OnPropertyChanged(string propertyName)
{
PropertyChangedEventHandler handler = PropertyChanged;
if (null != handler)
{
handler.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
}
}
然后再定义一个 演示数据集合类:
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Windows.Markup;
namespace BusinessObject
{
/// <summary>
/// 地区数据项
/// </summary>
[ContentProperty("Children")]//指示Children属性是 XAML 的Content内容属性
public class PlaceItem : INotifyPropertyChanged
{
/// <summary>
/// 构造函数
/// </summary>
public PlaceItem()
{
Children = new Collection<PlaceItem>();
IsSelected = true;
}
/// <summary>
/// 地区名称
/// </summary>
public string Name { get; set; }
/// <summary>
/// 地区描述
/// </summary>
public string Description { get; set; }
/// <summary>
/// 得到下级元素容器
/// </summary>
public Collection<PlaceItem> Children { get; private set; }
/// <summary>
/// 是否有子项
/// </summary>
public bool HasChild
{
get
{
return Children.Count > 0;
}
}
/// <summary>
/// 是否选中
/// </summary>
private bool? _isSelected;
/// <summary>
/// 该特性是否想要被安装
/// </summary>
public bool? IsSelected
{
get
{
return _isSelected;
}
set
{
if (value != _isSelected)
{
_isSelected = value;
OnPropertyChanged("IsSelected");
}
}
}
public event PropertyChangedEventHandler PropertyChanged;
/// <summary>
/// 属性改变时触发事件
/// </summary>
/// <param name="propertyName">Property that changed.</param>
private void OnPropertyChanged(string propertyName)
{
PropertyChangedEventHandler handler = PropertyChanged;
if (null != handler)
{
handler.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
}
}
好了，开始干正事儿了:
toolkit中的treeview用法
xaml部分
<UserControl x:Class="ToolKit.MainPage"
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"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="400"
xmlns:sdk="http://schemas.microsoft.com/winfx/2006/xaml/presentation/sdk"
xmlns:toolkit="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Toolkit"
xmlns:local="clr-namespace:BusinessObject;assembly=BusinessObject"
xmlns:common="clr-namespace:System.Windows;assembly=System.Windows.Controls">
<Grid x:Name="LayoutRoot" Background="White">
<Grid.Resources>
<!--定义数据源-->
<local:SampleData x:Key="SampleDataSource"></local:SampleData>
<!--定义模板-->
<common:HierarchicalDataTemplate x:Key="NodeTemplate" ItemsSource="{Binding Children}">
<StackPanel Orientation="Horizontal" ToolTipService.ToolTip="{Binding Description}">
<CheckBox
IsTabStop="False"
IsThreeState="{Binding HasChild}"
IsChecked="{Binding IsSelected, Mode=TwoWay}"
Click="ItemCheckbox_Click"
/>
<ContentPresenter Content="{Binding Name}" />
</StackPanel>
</common:HierarchicalDataTemplate>
</Grid.Resources>
<sdk:TreeView Name="treeView1" ItemTemplate="{StaticResource NodeTemplate}"
ItemsSource="{Binding Source={StaticResource SampleDataSource}, Path=SamplePlaceItemCollection}" Margin="10" BorderThickness="0">
<sdk:TreeView.ItemContainerStyle>
<Style TargetType="sdk:TreeViewItem">
<!--默认全展开-->
<Setter Property="IsExpanded" Value="True"/>
</Style>
</sdk:TreeView.ItemContainerStyle>
</sdk:TreeView>
</Grid>
</UserControl>
后端cs部分：
using System.Linq;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using BusinessObject;
namespace ToolKit
{
public partial class MainPage : UserControl
{
public MainPage()
{
InitializeComponent();
this.Loaded += new RoutedEventHandler(MainPage_Loaded);
}
void MainPage_Loaded(object sender, RoutedEventArgs e)
{
this.treeView1.ItemsSource = SampleData.SamplePlaceItemCollection;
this.treeView1.ExpandAll();
//var obj = this.treeView1.Items[1];
}
/// <summary>
/// 点击节点时，选中子节点，同时设置父节点状态
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void ItemCheckbox_Click(object sender, RoutedEventArgs e)
{
TreeViewItem item = GetParentTreeViewItem((DependencyObject)sender);
if (item != null)
{
PlaceItem feature = item.DataContext as PlaceItem;
if (feature != null)
{
UpdateChildrenCheckedState(feature);
UpdateParentCheckedState(item);
}
}
}
/// <summary>
/// 取得节点的父节点
/// </summary>
/// <param name="item"></param>
/// <returns></returns>
private static TreeViewItem GetParentTreeViewItem(DependencyObject item)
{
if (item != null)
{
DependencyObject parent = VisualTreeHelper.GetParent(item);
TreeViewItem parentTreeViewItem = parent as TreeViewItem;
return (parentTreeViewItem != null) ? parentTreeViewItem : GetParentTreeViewItem(parent);
}
return null;
}
/// <summary>
/// 更新父节点的选中状态
/// </summary>
/// <param name="item"></param>
private static void UpdateParentCheckedState(TreeViewItem item)
{
//取得父节点
TreeViewItem parent = GetParentTreeViewItem(item);
if (parent != null)
{
PlaceItem parentItem = parent.DataContext as PlaceItem;
if (parentItem != null)
{
bool? childrenCheckedState = parentItem.Children.First<PlaceItem>().IsSelected;
for (int i = 1; i < parentItem.Children.Count(); i++)
{
if (childrenCheckedState != parentItem.Children[i].IsSelected)
{
childrenCheckedState = null;
break;
}
}
parentItem.IsSelected = childrenCheckedState;
//递归处理上级父节点
UpdateParentCheckedState(parent);
}
}
}
/// <summary>
/// 更新子节点选中状态
/// </summary>
/// <param name="feature"></param>
private static void UpdateChildrenCheckedState(PlaceItem feature)
{
if (feature.IsSelected.HasValue)
{
foreach (PlaceItem childFeature in feature.Children)
{
childFeature.IsSelected = feature.IsSelected;
if (childFeature.Children.Count() > 0)
{
UpdateChildrenCheckedState(childFeature);
}
}
}
}
}
}
可以看到了，为了处理实现全选等功能，后端还是要写一些代码处理
telerik的treeview用法:
<UserControl x:Class="Telerik.MainPage"
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"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="400"
xmlns:common="clr-namespace:BusinessObject;assembly=BusinessObject"
xmlns:telerik="http://schemas.telerik.com/2008/xaml/presentation">
<Grid x:Name="LayoutRoot" Background="White">
<Grid.Resources>
<common:SampleData x:Key="SampleDataSource"></common:SampleData>
<!--数据节点模板-->
<DataTemplate x:Key="NodeTemplate">
<TextBlock Text="{Binding Name}" />
</DataTemplate>
<!--子节点模板-->
<telerik:HierarchicalDataTemplate x:Key="ChildTemplate" ItemTemplate="{StaticResource NodeTemplate}"
ItemsSource="{Binding Children}">
<TextBlock Text="{Binding Name}" />
</telerik:HierarchicalDataTemplate>
<!--父节点模板-->
<telerik:HierarchicalDataTemplate x:Key="ParentTemplate" ItemTemplate="{StaticResource ChildTemplate}"
ItemsSource="{Binding Children}">
<TextBlock Text="{Binding Name}" />
</telerik:HierarchicalDataTemplate>
</Grid.Resources>
<telerik:RadTreeView
ItemsSource="{Binding Source={StaticResource SampleDataSource}, Path=SamplePlaceItemCollection}"
ItemTemplate="{StaticResource ParentTemplate}" SelectionMode="Extended" IsLineEnabled="True" ItemsOptionListType="CheckList" IsOptionElementsEnabled="True"
IsRootLinesEnabled="True" IsTriStateMode="True" Margin="10">
<telerik:RadTreeView.ItemContainerStyle>
<Style TargetType="telerik:RadTreeViewItem">
<!--默认全展开-->
<Setter Property="IsExpanded" Value="True"/>
</Style>
</telerik:RadTreeView.ItemContainerStyle>
</telerik:RadTreeView>
</Grid>
</UserControl>
后端代码：木有！--商业控件，就是靠谱，很多功能已经帮开发者实现了.
效果：
