我在互联网上找不到这个问题的解决方案。有人可以建议我纠正这个问题。非常感谢您的帮助！
我试图在主窗口中将 UserControl 宽度设置为 Listview 的 ActualWidth。
<UserControl ...
Width="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListView}}, Path=ActualWidth}">
在 MainWindow 中，我添加了代码以通过 ViewModel 命令绑定单击按钮将 Usercontrols 添加到 ListView。
UserControl1 uc1 = new UserControl1();
ViewCollection.Add(uc1);
我注意到的是，如果在 ListView 的显示区域中添加了 usercontrol，那么创建的 usercontrol 的宽度会拉伸到 ListView 的宽度。此外，在调整窗口大小时，此用户控件的大小始终调整为 ListView 宽度。
但是如果在 ListView 的非显示区域中添加了 usercontrol（当添加了 UserControl 的地方没有滚动滚动条时），那么 usercontrol 会以其原始定义的宽度创建，并且 usercontrol 不会调整为 listview 宽度。我还可以在 OutputWindow (Debug) 中看到绑定错误：
System.Windows.Data 错误：4：找不到与引用“RelativeSource FindAncestor，AncestorType='System.Windows.Controls.ListView'，AncestorLevel='1''的绑定源。绑定表达式：路径=实际宽度；数据项=空；目标元素是'UserControl1'（名称=''）；目标属性是“宽度”（类型“双”）
<UserControl x:Class="BindingUCWidth.UserControl1"
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"
Width="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=ListView},
Path=ActualWidth}">
<Grid>
<GroupBox Header="User Control 1">
<StackPanel Orientation="Vertical">
<Button Content="hello1" Width="Auto"/>
<Button Content="hello2" Width="Auto"/>
</StackPanel>
</GroupBox>
</Grid>
</UserControl>
<Window x:Class="BindingUCWidth.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:BindingUCWidth"
mc:Ignorable="d"
Title="MainWindow" Height="450" Width="800">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="30"/>
<RowDefinition/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="1*"/>
<ColumnDefinition Width="1*"/>
</Grid.ColumnDefinitions>
<Button Grid.Row="0" Grid.Column="0" Content="Add UC 1" Command="{Binding AddUC1Command}"/>
<Button Grid.Row="0" Grid.Column="1" Content="Add UC 2" Command="{Binding AddUC2Command}"/>
<ListView x:Name="ViewsList" Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="2" ItemsSource="{Binding ViewCollection}"
BorderBrush="Black" BorderThickness="1,1,1,1" Margin="1"
HorizontalAlignment="Stretch" VerticalAlignment="Stretch"
HorizontalContentAlignment="Stretch" VerticalContentAlignment="Bottom"
ScrollViewer.CanContentScroll="True" ScrollViewer.VerticalScrollBarVisibility="Visible">
<ListView.ItemContainerStyle>
<Style TargetType="ListViewItem">
<Setter Property="Focusable" Value="True"/>
<Setter Property="HorizontalAlignment" Value="Left"/>
<Setter Property="HorizontalContentAlignment" Value="Stretch"/>
</Style>
</ListView.ItemContainerStyle>
</ListView>
</Grid>
using System;
using System.Windows.Input;
namespace BindingUCWidth
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
MainViewModel mvm = new MainViewModel();
this.DataContext = mvm;
}
}
public class MainViewModel
{
public ObservableCollection<UserControl> ViewCollection { get; set; }
public ICommand AddUC1Command { get; set; }
public ICommand AddUC2Command { get; set; }
public MainViewModel()
{
ViewCollection = new ObservableCollection<UserControl>();
AddUC1Command = new RelayCommand(param => AddUC1RelayCommand());
AddUC2Command = new RelayCommand(param => AddUC2RelayCommand());
}
private void AddUC1RelayCommand()
{
UserControl1 uc1 = new UserControl1();
ViewCollection.Add(uc1);
}
private void AddUC2RelayCommand()
{
UserControl2 uc2 = new UserControl2();
ViewCollection.Add(uc2);
}
}
public class RelayCommand : ICommand
{
private Action<object> execute;
private Func<object, bool> canExecute;
public event EventHandler CanExecuteChanged
{
add { CommandManager.RequerySuggested += value; }
remove { CommandManager.RequerySuggested -= value; }
}
public RelayCommand(Action<object> execute, Func<object, bool> canExecute = null)
{
this.execute = execute;
this.canExecute = canExecute;
}
public bool CanExecute(object parameter)
{
return this.canExecute == null || this.canExecute(parameter);
}
public void Execute(object parameter)
{
this.execute(parameter);
}
}
}
附加图像文件。
