三、数据绑定与模板样式
说明：通过学习本文内容，您将了解到怎样动态地进行关于TreeView组件的数据绑定以及TreeViewItem组件的模板样式更改。本文给出基本的使用方法。
注：在Silverlight项目文件夹下建立Icon文件夹，向里面添加3个16*16的png格式的图像。关于动态数据绑定这里只给出了基本的使用方法，在实际开发中可以使用WebService、XML等进行数据绑定。
效果图：
Feature.cs(业务模型)代码：
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Windows.Markup;
namespace SilverlightClient
{
[ContentProperty("Subcomponents")] //声明可在XAML文件中显示的内容属性
public class Feature : INotifyPropertyChanged //继承接口INotifyPropertyChanged用于双向数据绑定
{
//Feature对象的属性
public string FeatureName { get; set; }
public string Description { get; set; }
public string Icon { get; set; }//用以添加TreeViewItem项的图标
//声明全局变量
public Collection<Feature> Subcomponents { get; private set; }
private bool? _shouldInstall;
//是否有子组件
public bool HasSubcomponents
{
get
{
return Subcomponents.Count > 0;
}
}
//是否允许Feature进行安置
public bool? ShouldInstall
{
get
{
return _shouldInstall;
}
set
{
if (value != _shouldInstall)
{
_shouldInstall = value;
OnPropertyChanged("ShouldInstall");
}
}
}
//构造函数
public Feature()
{
Subcomponents = new Collection<Feature>();
ShouldInstall = true;
}
//事件委托
public event PropertyChangedEventHandler PropertyChanged;
//实现接口INotifyPropertyChanged定义函数
private void OnPropertyChanged(string propertyName)
{
PropertyChangedEventHandler handler = PropertyChanged;
if (null != handler)
{
handler.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
}
}
MainPage.xaml文件代码：
<UserControl
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:toolkit="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Toolkit"
xmlns:controls="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls"
xmlns:common="clr-namespace:System.Windows;assembly=System.Windows.Controls"
xmlns:samplesCommon="clr-namespace:SilverlightClient"
mc:Ignorable="d" x:Class="SilverlightClient.MainPage"
Width="640" Height="480">
<Grid x:Name="LayoutRoot" Background="White" Width="640" Height="480">
<StackPanel>
<StackPanel.Resources>
<!-- TreeViewItem风格设定 -->
<Style x:Key="PurpleItemStyle" TargetType="controls:TreeViewItem">
<Setter Property="Foreground" Value="Purple" />
<Setter Property="FontWeight" Value="Bold" />
</Style>
<!-- 代表一个Feature项的模板 -->
<common:HierarchicalDataTemplate x:Key="NodeTemplate" ItemsSource="{Binding Subcomponents}" ItemContainerStyle="{StaticResource PurpleItemStyle}">
<StackPanel Orientation="Horizontal" ToolTipService.ToolTip="{Binding Description}">
<Image Source="{Binding Icon}" /><!-- 图标绑定 -->
<ContentPresenter Content=" " />
<ContentPresenter Content="{Binding FeatureName}" />
</StackPanel>
</common:HierarchicalDataTemplate>
</StackPanel.Resources>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="2*" />
</Grid.ColumnDefinitions>
<controls:TreeView x:Name="tvFeature"
ItemTemplate="{StaticResource NodeTemplate}"
Grid.Column="0"
FontSize="14">
<!-- 用来一次展开TreeView所有结点 -->
<controls:TreeView.ItemContainerStyle>
<Style TargetType="controls:TreeViewItem">
<Setter