Question

我正在尝试访问listview中的文本块和文本框，但无法在C＃代码中获取它们，因为它们位于ItemTemplate和DataTemplate中。以下是XAML代码的示例：

<ListView x:Name="VehicleList" HorizontalAlignment="Center" Height="120" Margin="0" VerticalAlignment="Center" Width="1119" Background="{ThemeResource CheckBoxDisabledForegroundThemeBrush}" SelectionChanged="VehicleList_SelectionChanged">
        <ListView.ItemTemplate>
            <DataTemplate>
                <Grid x:Name="VehicleGrid" Height="52" Width="1117" HorizontalAlignment="Center" VerticalAlignment="Center" Margin="20,0,0,0">
                    <Grid.ColumnDefinitions>
                        <ColumnDefinition Width="318*"/>
                        <ColumnDefinition Width="425*"/>
                        <ColumnDefinition Width="366*"/>
                    </Grid.ColumnDefinitions>
                    <TextBlock x:Name="Year" Grid.Column="0" TextWrapping="Wrap" Text="{Binding Year}" HorizontalAlignment="Center" VerticalAlignment="Center" Margin="0,20,0,0" Height="52" Grid.ColumnSpan="1" TextAlignment="Center" Width="321" FontSize="26.667"/>
                    <TextBlock x:Name="Make" Grid.Column="1" TextWrapping="Wrap" Text="{Binding Make}" HorizontalAlignment="Center" VerticalAlignment="Center" Margin="0,20,0,0" Height="52" Grid.ColumnSpan="1" TextAlignment="Center" Width="425" FontSize="26.667" />
                    <TextBlock x:Name="Model" Grid.Column="2" TextWrapping="Wrap" Text="{Binding Model}" HorizontalAlignment="Center" VerticalAlignment="Center" Margin="0,20,0,0" Height="52" Grid.ColumnSpan="1" TextAlignment="Center" Width="366" FontSize="26.667"/>
                    <TextBox x:Name="AddYear" Grid.Column="0" TextWrapping="Wrap" Text="TextBlock" HorizontalAlignment="Center" VerticalAlignment="Center" Height="52" Grid.ColumnSpan="1" TextAlignment="Center" Width="321" FontSize="26.667" Visibility="Collapsed"/>
                    <TextBox x:Name="AddMake" Grid.Column="1" TextWrapping="Wrap" Text="TextBlock" HorizontalAlignment="Center" VerticalAlignment="Center" Height="52" Grid.ColumnSpan="1" TextAlignment="Center" Width="425" FontSize="26.667" Visibility="Collapsed"/>
                    <TextBox x:Name="AddModel" Grid.Column="2" TextWrapping="Wrap" Text="TextBlock" HorizontalAlignment="Center" VerticalAlignment="Center" Height="52" Grid.ColumnSpan="1" TextAlignment="Center" Width="366" FontSize="26.667" Visibility="Collapsed"/>
                </Grid>
            </DataTemplate>
        </ListView.ItemTemplate>
    </ListView>

无论如何都要在DataTemplate中获取项目吗？

Answer 1

您的问题对于所有XAML风格都是通用的，在WPF和Silverlight中也是如此。问题是你的DataTemplate。请记住，XAML会为列表中的每个项目注入一次DataTemplate的内容。这意味着您的名称只能存在于DataTemplate实例的范围内。

如果你为模板做了代码，你可以通过创建UserControl做得更好。请参阅下面的示例：

<!-- most boiler plate code skipped -->
<UserControl x:Class="MyProject.VehicleListItem">
    <Grid x:Name="VehicleGrid" Height="52" Width="1117" HorizontalAlignment="Center" VerticalAlignment="Center" Margin="20,0,0,0">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="318*"/>
            <ColumnDefinition Width="425*"/>
            <ColumnDefinition Width="366*"/>
        </Grid.ColumnDefinitions>
        <TextBlock x:Name="Year" Grid.Column="0" TextWrapping="Wrap" Text="{Binding Year}" HorizontalAlignment="Center" VerticalAlignment="Center" Margin="0,20,0,0" Height="52" Grid.ColumnSpan="1" TextAlignment="Center" Width="321" FontSize="26.667"/>
        <TextBlock x:Name="Make" Grid.Column="1" TextWrapping="Wrap" Text="{Binding Make}" HorizontalAlignment="Center" VerticalAlignment="Center" Margin="0,20,0,0" Height="52" Grid.ColumnSpan="1" TextAlignment="Center" Width="425" FontSize="26.667" />
        <TextBlock x:Name="Model" Grid.Column="2" TextWrapping="Wrap" Text="{Binding Model}" HorizontalAlignment="Center" VerticalAlignment="Center" Margin="0,20,0,0" Height="52" Grid.ColumnSpan="1" TextAlignment="Center" Width="366" FontSize="26.667"/>
        <TextBox x:Name="AddYear" Grid.Column="0" TextWrapping="Wrap" Text="TextBlock" HorizontalAlignment="Center" VerticalAlignment="Center" Height="52" Grid.ColumnSpan="1" TextAlignment="Center" Width="321" FontSize="26.667" Visibility="Collapsed"/>
        <TextBox x:Name="AddMake" Grid.Column="1" TextWrapping="Wrap" Text="TextBlock" HorizontalAlignment="Center" VerticalAlignment="Center" Height="52" Grid.ColumnSpan="1" TextAlignment="Center" Width="425" FontSize="26.667" Visibility="Collapsed"/>
        <TextBox x:Name="AddModel" Grid.Column="2" TextWrapping="Wrap" Text="TextBlock" HorizontalAlignment="Center" VerticalAlignment="Center" Height="52" Grid.ColumnSpan="1" TextAlignment="Center" Width="366" FontSize="26.667" Visibility="Collapsed"/>
    </Grid>
</UserControl>

那就是你可以从一个可以实例化的UserControl做你需要做的一切，有自己的代码，等等。你可以按照自己想要的方式工作，然后在列表中需要它时引用它这样：

<ListView x:Name="VehicleList" HorizontalAlignment="Center" Height="120" Margin="0" VerticalAlignment="Center" Width="1119" Background="{ThemeResource CheckBoxDisabledForegroundThemeBrush}" SelectionChanged="VehicleList_SelectionChanged">
    <ListView.ItemTemplate>
        <DataTemplate>
            <myProject:VehicleListItem/>
        </DataTemplate>
    </ListView.ItemTemplate>
</ListView>

ListView会将车辆项目分配给您的用户控件的DataContext，一切都会像您设计的那样工作。

有一种方法可以在后面的代码中获取可视树，但它非常复杂。基本上，您需要使用ListView.ItemContainerGenerator并调用ContainerFromItem(dataItem)（ref），然后沿着您从中获取的可视树向下走。这不仅是一件非常痛苦的事情，也无法保证从WPF到UWP或SilverLight都可以访问所有API。最干净的解决方案是将代码分解成独立的部分。

另一种解决方案，可能更清晰，我建议的是利用绑定对象。 ListView.SelectedItem返回绑定到DataTemplate的对象。只需从该对象获取值。如果您的ViewModel包含AddYear，AddMake和AddModel的属性，那么由于您根本不处理XAML，因此很容易完成许多工作。< / p>

Answer 2

如果您可以通过按钮单击执行此操作;您可以使用CommandParameter或遍历VisualTree，就像这两个链接建议：

here

How to get text from TextBox inside ListViewItem's DataTemplate

Answer 3

<强>用户控件

听起来像UserControl就是你要找的东西。

项目→添加用户控件

由于您已经拥有XAML设计，因此应该很容易。后面的代码看起来像这样：

public class VehicleView : UserControl
{
    // Year
    public static readonly DependencyProperty YearProperty =
        DependencyProperty.Register("Year", typeof(int), typeof(VehicleView),
            new PropertyMetadata());

    public int Year
    {
        get { return (int)GetValue(YearProperty); }
        set { SetValue(YearProperty, value); }
    }

    // Make
    public static readonly DependencyProperty MakeProperty =
        DependencyProperty.Register("Make", typeof(string), typeof(VehicleView),
            new PropertyMetadata("None"));

    public string Make
    {
        get { return (string)GetValue(MakeProperty); }
        set { SetValue(MakeProperty, value); }
    }

    // Model
    public static readonly DependencyProperty ModelProperty =
        DependencyProperty.Register("Model", typeof(string), typeof(VehicleView),
            new PropertyMetadata("None"));

    public string Model
    {
        get { return (string)GetValue(ModelProperty); }
        set { SetValue(ModelProperty, value); }
    }

    public VehicleView()
    {
        InitializeComponent();
    }
}

以相同的方式绑定单词。只需使用x:Name命名UserControl即可。类似的东西：

<UserControl x:Name="vehicleview"
             x:Class="MyProjectClass"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
             mc:Ignorable="d">

    <Grid>
        <!-- Here's where your ListView goes. -->
        <TextBox Text="{Binding ElementName=vehicleview, Path=Model}"/>
    <Grid>

</UserControl>

Answer 4

我可以看到你使用过绑定。

在VehicleList_SelectionChanged上，您可以执行以下操作

List<YouClass-Model> selectedItems = VehicleList.SelectedItems.Cast<YouClass-Model>().ToList();

或者如果您使用ItemClicked EventHandler

 YouClass-Model itemClicked = (YouClass-Model)e.ClickedItem)

这样您就可以加载绑定数据。前itemClicked.Model

还要确保正确绑定数据

Data binding overview

INotifyPropertyChanged.PropertyChanged

Answer 5

要从索引或数据中获取UI控件，请使用listView.ContainerFromIndex或listView.ContainerFromItem。这是UWP中公认的方法。

C＃UWP在ListView的ItemTemplate中获取项目

5 个答案: