【windows phone】CollectionViewSource的妙用

在windows phone中绑定集合数据的时候，有时候需要分层数据，通常需要以主从试图形式显示。通常的方法是将第二个ListBox（主视图）的数据源绑定到第一个ListBox

（从视图）的SelectedItem，或者通过第一个ListBox的SelectionChanged事件来设置绑定。但是借助CollectionViewSource类可以更方便的实现；

CollectionView是一个集合视图类，支持数据的排序、分组、过滤。对数据的映像进行排列组合；

CollectionViewSource是CollectionView的一个XAML代理，可以在XAML中使用；

案例说明：用主从试图关系显示两个的员工列表；效果图如下：

前期工作，创建三个类来初始数据源；

（1）Employee.cs

    public class Employee{public int Number { get; set; } //工号public string  Name { get; set; } //姓名public string  Sex { get; set; } //性别public int BirthYear { get; set; } //出生年份}

（2）Department.cs

    public class Department:ObservableCollection<Employee>{public string DepName { get; set; }public ObservableCollection<Employee> Employees { get; set; }}

（3）DepartmentList.cs

    public class DepartmentList:ObservableCollection<Department>{public DepartmentList(){ObservableCollection<Employee> employee1 = new ObservableCollection<Employee> {new Employee{Number=2012,Name="netboy",Sex="boy",BirthYear=1992},new Employee{Number=2013,Name="dandan",Sex="girl",BirthYear=2000},new Employee{Number=2014,Name="xiaobai",Sex="girl",BirthYear=2012}};ObservableCollection<Employee> employee2 = new ObservableCollection<Employee> {new Employee{Number=2020,Name="kaizi",Sex="girl",BirthYear=2011},new Employee{Number=2021,Name="yangzai",Sex="gril",BirthYear=2010}};this.Add(new Department { DepName = "技术部", Employees = employee1 });this.Add(new Department { DepName = "商务部", Employees = employee2 });//ObservableCollection<Department> deparment = new ObservableCollection<Department> //{//    new Department{DepName="tengfei",Employees=employee1},//    new Department{DepName="google",Employees=employee2}//};}}

注意：使用ObservableCollection<T>的时候需要引用命名空间——using System.Collections.ObjectModel;

通过在新建页面的phone:PhoneApplicationPage标记中添加一个命名空间映射。代码如下：

xmlns:local="clr-namespace:数据绑定"//我的项目为“数据绑定”

添加资源字典：

   <phone:PhoneApplicationPage.Resources><local:DepartmentList x:Key="deplist"/><CollectionViewSource x:Key="departmentView"Source="{StaticResource deplist}"/><DataTemplate x:Key="dtEmployees"><StackPanel Height="50"HorizontalAlignment="Center"Width="480"VerticalAlignment="Top"Orientation="Horizontal"><TextBlock Height="50"HorizontalAlignment="Left"Width="90"Text="{Binding Number}"/><TextBlock Height="50"Width="120"Text="{Binding Name}"/><TextBlock Height="50"Width="120"Text="{Binding BirthYear}"/><TextBlock Height="50"Width="120"Text="{Binding Sex}"/></StackPanel></DataTemplate></phone:PhoneApplicationPage.Resources>

在布局页面中添加如下代码：

            <TextBlock Width="300"Height="50"FontSize="36"Text="请选择部门:"HorizontalAlignment="Left"VerticalAlignment="Top"Margin="10,30,0,0"/><ListBox Name="lb1"Height="100"Width="156"DisplayMemberPath="DepName"ItemsSource="{Binding Source={StaticResource departmentView}}"Margin="40,86,260,0"HorizontalAlignment="Center"VerticalAlignment="Top" FontSize="32" /><TextBlock Height="62"Width="111"HorizontalAlignment="Left"VerticalAlignment="Top"Text="{Binding Path=DepName,Source={StaticResource departmentView}}"Foreground="Red" Margin="12,210,0,0" FontSize="32" /><TextBlock Height="50"HorizontalAlignment="Right"Text="员工列表"VerticalAlignment="Top" Margin="0,210,169,0" Width="158" FontSize="32" /><TextBlock Height="50"HorizontalAlignment="Left"Width="120"Text="性别" Margin="344,278,0,279" FontSize="32" /><TextBlock Height="50" Text="出生日期" Margin="204,278,112,279" FontSize="32" /><TextBlock Height="50"Width="120"Text="工号" Margin="6,278,330,279" FontSize="32" /><TextBlock Height="50"Width="98"Text="名字" Margin="0,278,260,279" HorizontalAlignment="Right" FontSize="32" /><ListBox Name="lb2"Height="170"VerticalAlignment="Top"ItemsSource="{Binding Path=Employees,Source={StaticResource departmentView}}"ItemTemplate="{StaticResource dtEmployees}" Margin="12,334,-46,0" FontSize="32" />