WPF 数据绑定 定制一个集合的视图

//排序
private void SortHelper(string propertyName)
{
//返回给定源的默认视图
//ICollectionView view = CollectionViewSource.GetDefaultView(this.FindResource("photoList");
ICollectionView view = CollectionViewSource.GetDefaultView(pl);

//ICollectionView的SortDescriptions属性来控制视图排序
if (view.SortDescriptions.Count > 0
&& view.SortDescriptions[0].PropertyName == propertyName
&& view.SortDescriptions[0].Direction == ListSortDirection.Ascending)
{
view.SortDescriptions.Clear();
view.SortDescriptions.Add(new SortDescription(propertyName, ListSortDirection.Descending));
}
else
{
view.SortDescriptions.Clear();
view.SortDescriptions.Add(new SortDescription(propertyName, ListSortDirection.Ascending));
}
}

//调用
SortHelper("Name");

//转换时间为指定格式
class DateTimeToDateConverter : IValueConverter
{

#region IValueConverter 成员

public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
return ((DateTime)value).ToString("dd/MM/yyyy");
}

public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
throw new NotImplementedException();
}

#endregion
}

//分组
private void GroupHelper(string propertyName)
{
ICollectionView view = CollectionViewSource.GetDefaultView(pl);

//ICollectionView的GroupDescriptions属性来控制视图排序
view.GroupDescriptions.Clear();
//用指定属性名，转换器分组
view.GroupDescriptions.Add(new PropertyGroupDescription(propertyName, new DateTimeToDateConverter()));
}

//调用，按DateTime属性分组
GroupHelper("DateTime");

<ListBox x:Name="listBox1" SelectedValuePath="Name" ItemsSource="{Binding}"
IsSynchronizedWithCurrentItem="True" SelectionChanged="listBox2_SelectionChanged">
<ListBox.GroupStyle>
<GroupStyle>
<!-- 定义分组头外观 -->
<GroupStyle.HeaderTemplate>
<!-- 数据模板会有一特殊CollectionViewGroup对象数据上下文 -->
<DataTemplate>
<Border BorderBrush="Black" BorderThickness="1">
<!-- 该上下文包含一Name属性表示每个分组的名称，需要绑定 -->
<TextBlock Text="{Binding Path=Name}" FontWeight="Bold"/>
</Border>
</DataTemplate>
</GroupStyle.HeaderTemplate>
</GroupStyle>
</ListBox.GroupStyle>
</ListBox>

//过滤
private void FilterHelper()
{
ICollectionView view = CollectionViewSource.GetDefaultView(pl);

//ICollectionView的Filter委托对象，设置后会马上回调
//该委托的工作就是决定某项的显示（返回true）隐藏（返回false）
//要删除该过滤，只需Filter = null
view.Filter = delegate(object o)
{
return (DateTime.Now - (o as PhotoModel).DateTime).Days <= 1;
};
}

//调用
FilterHelper();