05. DataTemplate

zzyzxb

已于 2023-10-27 15:33:51 修改

阅读量96

点赞数

分类专栏： WPF 文章标签： wpf

于 2023-10-27 15:32:54 首次发布

本文链接：https://blog.youkuaiyun.com/zzyzxb/article/details/134077534

版权

WPF 专栏收录该内容

11 篇文章

订阅专栏

本文介绍了如何在WindowsPresentationFoundation(WPF)中使用DataTemplateSelector来根据数据类型动态地在集合控件中选择并显示不同View。开发者需创建DataTemplate实例，实现DataTypeTemplateSelector，然后与列表绑定，以实现视图的切换和样式定制。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

参考JusterZhu视频和文档，ppt文档基本全抄

一、DataTemplate

在日常开发中，会遇到需要在一个集合控件中通过某个Type属性选择不同的View显示在控件上。那么用常规的绑定是无法完成的，这时候微软提供了一个DataTemplateSelector对象帮助开发者完成此项功能。

实现步骤：
1.实现需要绑定的集合，并指定好类型
2.实现不同的DataTemplate，并实现好里面的样式
3.基于DataTemplateSelector实现自定义模板选择器
4.将DataTemplateSelector 、 DataTemplate、List、目标控件关联（绑定）起来。

<Window x:Class="test_05.MainWindow"
        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:local="clr-namespace:test_05"
        mc:Ignorable="d"
        Title="TestTemplateSelector" Height="450" Width="800">
    <Window.DataContext>
        <local:MainViewModel></local:MainViewModel>
    </Window.DataContext>

    <Window.Resources>
        <DataTemplate x:Key="OneDataTemplate" DataType="{x:Type local:MainModel}">
            <Border Background="{Binding Color}">
                <StackPanel Orientation="Horizontal">
                    <TextBlock Text="{Binding Name}" VerticalAlignment="Center"></TextBlock>
                    <Button Width="50" Height="30"></Button>
                </StackPanel>
            </Border>
        </DataTemplate>
        <DataTemplate x:Key="TwoDataTemplate" DataType="{x:Type local:MainModel}">
            <Border Background="{Binding Color}">
                <StackPanel Orientation="Horizontal">
                    <TextBlock Text="{Binding Name}" Width="100" 
                               VerticalAlignment="Center" HorizontalAlignment="Center"
                               TextAlignment="Center" />
                    <Border BorderBrush="Black" BorderThickness="5">
                        <Rectangle 
                            Width="50"
                            Height="30"
                            Fill="{Binding Color}" />
                    </Border>
                </StackPanel>
            </Border>
        </DataTemplate>
        <DataTemplate x:Key="ThreeDataTemplate" DataType="{x:Type local:MainModel}">
            <Border Background="{Binding Color}">
                <StackPanel Orientation="Horizontal">
                    <TextBlock Text="{Binding Name}" />
                    <Rectangle
                        Width="50"
                        Height="30"
                        Fill="{Binding Color}" />
                </StackPanel>
            </Border>
        </DataTemplate>
        <DataTemplate x:Key="FourDataTemplate" DataType="{x:Type local:MainModel}">
            <Border Background="{Binding Color}">
                <StackPanel Orientation="Horizontal">
                    <TextBlock Text="{Binding Name}" />
                    <Rectangle
                        Width="50"
                        Height="30"
                        Fill="{Binding Color}" />
                </StackPanel>
            </Border>
        </DataTemplate>
        <local:DataTypeTemplateSelector x:Key="test"></local:DataTypeTemplateSelector>
    </Window.Resources>

    <Grid>
        <ListBox ItemTemplateSelector="{StaticResource test}" ItemsSource="{Binding mainModels}"></ListBox>
    </Grid>
</Window>

internal class DataTypeTemplateSelector: DataTemplateSelector
{
    public override DataTemplate SelectTemplate(object item, DependencyObject container)
    {
        if (item is MainModel)
        {
            var model = item as MainModel;
            switch (model.Person) 
            {
                case Person.One:
                    return (container as FrameworkElement).FindResource("OneDataTemplate") as DataTemplate;
                case Person.Two:
                    return (container as FrameworkElement).FindResource("TwoDataTemplate") as DataTemplate;
                case Person.Three:
                    return (container as FrameworkElement).FindResource("ThreeDataTemplate") as DataTemplate;
                case Person.Four:
                    return (container as FrameworkElement).FindResource("FourDataTemplate") as DataTemplate;
            }
        }

        return base.SelectTemplate(item, container);
    }
}

public enum Person
{
    One, 
    Two, 
    Three, 
    Four 
}

internal class MainModel
{
    public string Name {  get; set; }
    public Person Person { get; set; }
    public string Color {  get; set; } 
}

internal class MainViewModel
{
    public ObservableCollection<MainModel> mainModels { get; set; }
    public MainViewModel()
    {
        mainModels = new ObservableCollection<MainModel>
        {
            new MainModel { Person = Person.One, Name = "dawa", Color = "Red" },
            new MainModel { Person = Person.Two, Name = "erwa", Color = "Green" },
            new MainModel { Person = Person.Three, Name = "sanwa", Color = "Blue" },
            new MainModel { Person = Person.Four, Name = "siwa", Color = "Yellow" }
        };
    }
}