如何:为 ListView 创建自定义视图模式
本示例演示如何为 ListView 控件创建自定义 View 模式。
示例
当为 ListView 控件创建自定义视图时,必须使用 ViewBase 类。 下面的示例演示了称为 PlainView 的视图模式,它是从 ViewBase 类派生的。
Public Class PlainView
Inherits ViewBase
Public Shared ReadOnly ItemContainerStyleProperty As DependencyProperty = ItemsControl.ItemContainerStyleProperty.AddOwner(GetType(PlainView))
Public Property ItemContainerStyle() As Style
Get
Return CType(GetValue(ItemContainerStyleProperty), Style)
End Get
Set(ByVal value As Style)
SetValue(ItemContainerStyleProperty, value)
End Set
End Property
Public Shared ReadOnly ItemTemplateProperty As DependencyProperty = ItemsControl.ItemTemplateProperty.AddOwner(GetType(PlainView))
Public Property ItemTemplate() As DataTemplate
Get
Return CType(GetValue(ItemTemplateProperty), DataTemplate)
End Get
Set(ByVal value As DataTemplate)
SetValue(ItemTemplateProperty, value)
End Set
End Property
Public Shared ReadOnly ItemWidthProperty As DependencyProperty = WrapPanel.ItemWidthProperty.AddOwner(GetType(PlainView))
Public Property ItemWidth() As Double
Get
Return CDbl(GetValue(ItemWidthProperty))
End Get
Set(ByVal value As Double)
SetValue(ItemWidthProperty, value)
End Set
End Property
Public Shared ReadOnly ItemHeightProperty As DependencyProperty = WrapPanel.ItemHeightProperty.AddOwner(GetType(PlainView))
Public Property ItemHeight() As Double
Get
Return CDbl(GetValue(ItemHeightProperty))
End Get
Set(ByVal value As Double)
SetValue(ItemHeightProperty, value)
End Set
End Property
Protected Overrides ReadOnly Property DefaultStyleKey() As Object
Get
Return New ComponentResourceKey(Me.GetType(), "myPlainViewDSK")
End Get
End Property
End Class
public class PlainView : ViewBase
{
public static readonly DependencyProperty
ItemContainerStyleProperty =
ItemsControl.ItemContainerStyleProperty.AddOwner(typeof(PlainView));
public Style ItemContainerStyle
{
get { return (Style)GetValue(ItemContainerStyleProperty); }
set { SetValue(ItemContainerStyleProperty, value); }
}
public static readonly DependencyProperty ItemTemplateProperty =
ItemsControl.ItemTemplateProperty.AddOwner(typeof(PlainView));
public DataTemplate ItemTemplate
{
get { return (DataTemplate)GetValue(ItemTemplateProperty); }
set { SetValue(ItemTemplateProperty, value); }
}
public static readonly DependencyProperty ItemWidthProperty =
WrapPanel.ItemWidthProperty.AddOwner(typeof(PlainView));
public double ItemWidth
{
get { return (double)GetValue(ItemWidthProperty); }
set { SetValue(ItemWidthProperty, value); }
}
public static readonly DependencyProperty ItemHeightProperty =
WrapPanel.ItemHeightProperty.AddOwner(typeof(PlainView));
public double ItemHeight
{
get { return (double)GetValue(ItemHeightProperty); }
set { SetValue(ItemHeightProperty, value); }
}
protected override object DefaultStyleKey
{
get
{
return new ComponentResourceKey(GetType(), "myPlainViewDSK");
}
}
}
若要向自定义视图应用样式,应使用 Style 类。 下面的示例为 PlainView 视图模式定义 Style。 在前面的示例中,此样式设置为 DefaultStyleKey 属性的值,该属性是为 PlainView 定义的。
<Style x:Key="{ComponentResourceKey
TypeInTargetAssembly={x:Type l:PlainView},
ResourceId=myPlainViewDSK}"
TargetType="{x:Type ListView}"
BasedOn="{StaticResource {x:Type ListBox}}"
>
<Setter Property="HorizontalContentAlignment"
Value="Center"/>
<Setter Property="ItemContainerStyle"
Value="{Binding (ListView.View).ItemContainerStyle,
RelativeSource={RelativeSource Self}}"/>
<Setter Property="ItemTemplate"
Value="{Binding (ListView.View).ItemTemplate,
RelativeSource={RelativeSource Self}}"/>
<Setter Property="ItemsPanel">
<Setter.Value>
<ItemsPanelTemplate>
<WrapPanel Width="{Binding (FrameworkElement.ActualWidth),
RelativeSource={RelativeSource
AncestorType=ScrollContentPresenter}}"
ItemWidth="{Binding (ListView.View).ItemWidth,
RelativeSource={RelativeSource AncestorType=ListView}}"
MinWidth="{Binding (ListView.View).ItemWidth,
RelativeSource={RelativeSource AncestorType=ListView}}"
ItemHeight="{Binding (ListView.View).ItemHeight,
RelativeSource={RelativeSource AncestorType=ListView}}"/>
</ItemsPanelTemplate>
</Setter.Value>
</Setter>
</Style>
若要在自定义视图模式下定义数据的布局,应定义 DataTemplate 对象。 下面的示例定义一个可用于在 PlainView 视图模式下显示数据的 DataTemplate。
<DataTemplate x:Key="centralTile">
<StackPanel Height="100" Width="90">
<Grid Width="70" Height="70" HorizontalAlignment="Center">
<Image Source="{Binding XPath=@Image}" Margin="6,6,6,9"/>
</Grid>
<TextBlock Text="{Binding XPath=@Name}" FontSize="13"
HorizontalAlignment="Center" Margin="0,0,0,1" />
<TextBlock Text="{Binding XPath=@Type}" FontSize="9"
HorizontalAlignment="Center" Margin="0,0,0,1" />
</StackPanel>
</DataTemplate>
下面的示例演示如何为使用在前面的示例中定义的 DataTemplate 的 PlainView 视图模式定义 ResourceKey。
<l:PlainView x:Key="tileView"
ItemTemplate="{StaticResource centralTile}"
ItemWidth="100"/>
如果您将 View 属性设置为该资源键,则 ListView 控件可以使用自定义视图。 下面的示例演示如何将 PlainView 指定为 ListView 的视图模式。
'Set the ListView View property to the tileView custom view
lv.View = TryCast(lv.FindResource("tileView"), ViewBase)
//Set the ListView View property to the tileView custom view
lv.View = lv.FindResource("tileView") as ViewBase;
有关完整示例,请参见 ListView with Multiple Views Sample(具有多个视图的 ListView 示例)。