Windows Phone 8中包含多个ItemTemplates的ListBox

Question

我有一个ListBox,它是一个会话气泡列表(如消息传递应用程序),每个气泡可以来自用户或来自系统.因此,列表框中有两个DataTemplates,它们在资源中定义.如何有选择地将这些应用于ListBox？

我尝试过DataTemplateSelector(这是WP7的解决方案,但我找不到WP8中的类!),使用(WP8不支持DataType),最后是ItemTemplate属性的IValueConvertor - 一切都无济于事!

这样做的方法是什么？我想必须有一种方法,因为这是一个相当简单的要求？!

谢谢

Answer 1

DataTemplateSelector是ItemTemplates基于XAML数据绑定中的项类型进行更改的推荐方法.DataTemplateSelectorWP7没有内置,也没有WP8内置.你必须在网上找到你喜欢的版本DataTemplateSelector并使用它.或者只是滚动你自己,因为它是大约5-10行代码.

关于WP7中的自定义DataTemplateSelectors和基于该文章的DataTemplateSelector基类的 wp7nl项目,WindowsPhoneGeek上有一篇很好的文章.

<ListBox x:Name="listBox" HorizontalContentAlignment="Stretch">
    <ListBox.ItemTemplate>
        <DataTemplate>
            <local:FoodTemplateSelector Content="{Binding}">
                <local:FoodTemplateSelector.Healthy>
                    <DataTemplate>
                        <StackPanel Orientation="Horizontal" Background="YellowGreen" Width="400" Margin="10">
                            <Image Source="{Binding IconUri}" Stretch="None"/>
                            <TextBlock Text="{Binding Name}" FontSize="40" Foreground="Black" Width="280"/>
                            <TextBlock Text="healty" />
                        </StackPanel>
                    </DataTemplate>
                    </local:FoodTemplateSelector.Healthy>
                <local:FoodTemplateSelector.UnHealthy>
                    <DataTemplate>
                        <Border BorderBrush="Red" BorderThickness="2"  Width="400" Margin="10">
                        <StackPanel Orientation="Horizontal">
                            <Image Source="{Binding IconUri}" Stretch="None"/>
                                <TextBlock Text="{Binding Name}" FontSize="40" Width="280"/>
                            <Image Source="Images/attention.png" Stretch="None" Margin="10,0,0,0"/>
                        </StackPanel>
                        </Border>
                    </DataTemplate>
                </local:FoodTemplateSelector.UnHealthy>
                <local:FoodTemplateSelector.NotDetermined>
                    <DataTemplate>
                        <StackPanel Orientation="Horizontal" Background="Gray" Width="400" Margin="10">
                            <Image Source="{Binding IconUri}" Stretch="None"/>
                            <TextBlock Text="{Binding Name}" FontSize="40" Width="280"/>
                            <Image Source="Images/question.png" Stretch="None" Margin="10,0,0,0"/>
                        </StackPanel>
                    </DataTemplate>
                </local:FoodTemplateSelector.NotDetermined>
            </local:FoodTemplateSelector>
        </DataTemplate>
    </ListBox.ItemTemplate>
</ListBox>

如果您正在寻找更快速和更脏的解决方案,Prism的DataTemplateSelector不需要C#编码,因为它使用DataTemplateSelector.Resources集合来处理类型映射.这两个DataTemplateSelector类都可以复制出来并在您的应用中使用.

   1: <UserControl.Resources>
   2:     <DataTemplate x:Key="SelectorDataTemplate">
   3:         <prism:DataTemplateSelector Content="{Binding}"
   4:                                     HorizontalContentAlignment="Stretch"
   5:                                     IsTabStop="False">
   6:             <prism:DataTemplateSelector.Resources>
   7:                 <DataTemplate x:Key="DataType1">
   8:                     <StackPanel Orientation="Horizontal">
   9:                         <TextBlock Text="{Binding ID}"/>
  10:                         <toolkit:Separator />
  11:                         <TextBlock Text="{Binding Name}" />
  12:                     </StackPanel>
  13:                 </DataTemplate>
  14:  
  15:                 <DataTemplate x:Key="DataType2">
  16:                     <StackPanel Orientation="Horizontal">
  17:                         <TextBox Text="{Binding Index}" />
  18:                         <toolkit:Separator />
  19:                         <TextBox Text="{Binding Description}" />
  20:                     </StackPanel>
  21:                 </DataTemplate>
  22:  
  23:             </prism:DataTemplateSelector.Resources>
  24:         </prism:DataTemplateSelector>
  25:     </DataTemplate>
  26: </UserControl.Resources>

还有更多DataTemplateSelectors,包括:Odyssey Phone,UIMessage等.