树视图中的 WPF 列表视图选择 我需要在选择更改事件中获取所有选定的列表视图项目(按住 CTRL 键时)

Question

WPF 的新增功能

这是 Xaml 代码需要将所有选定的列表视图项放入选择更改事件

我尝试使用多选树视图nuget，但问题是在这种情况下父项和子项都相同。 TreeviewEX也做了同样的事情。任何帮助都会很棒。

<Window x:Class="DemoApps.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:DemoApps"
mc:Ignorable="d"
Title="MainWindow" Height="350" Width="525">
<Grid>
<TreeView x:Name="TreeViewList" Loaded="TreeViewList_Loaded">
<TreeView.ItemTemplate>
<HierarchicalDataTemplate DataType="{x:Type local:Group}" ItemsSource="{Binding Users}" >
<Grid Width="200" Height="auto">
<StackPanel>
<TextBlock Text="{Binding GroupName}"/>
</StackPanel>
</Grid>
<HierarchicalDataTemplate.ItemTemplate>
<DataTemplate DataType="{x:Type local:User}">
<ListView SelectionMode="Extended" SelectionChanged="ListView_SelectionChanged">
<Grid Width="150" Height="20">
<StackPanel>
<TextBlock Text="{Binding UserName}" />
</StackPanel>
</Grid>
</ListView>
</DataTemplate>
</HierarchicalDataTemplate.ItemTemplate>
</HierarchicalDataTemplate>

</TreeView.ItemTemplate>
<TreeView.ItemContainerStyle>
<Style TargetType="TreeViewItem">
<Setter Property="IsSelected" Value="{Binding IsSelected}" />
<Setter Property="IsExpanded" Value="{Binding IsExpanded}" />
</Style>
</TreeView.ItemContainerStyle>
</TreeView>
</Grid>
</Window>

这是我背后的代码

using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Windows;
using System.Windows.Controls;
namespace DemoApps
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public ObservableCollection<Group> GroupData { get; set; }
public MainWindow()
{
InitializeComponent();
GroupData = GetDummyData();
}
private ObservableCollection<Group> GetDummyData()
{
var _group = new ObservableCollection<Group>();
for (int i = 0; i < 20; i++)
{
_group.Add(new Group
{
GroupName = "Group name" + i,
Users = GetDummyUsers(i)
});
}
return _group;
}
private ObservableCollection<User> GetDummyUsers(int i)
{
var _user = new ObservableCollection<User>();
for (int j = 0; j < 10; j++)
{
_user.Add(new User
{
UserName = "User " + i + "-" + j
});
}
return _user;
}
private void TreeViewList_Loaded(object sender, RoutedEventArgs e)
{
TreeViewList.ItemsSource = GroupData;
}
private void ListView_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
//Need to get all selected items from List View.
//Here i need to get the selected items
}
}
public class Group : TreeViewItemBase
{
public string GroupName { get; set; }
public ObservableCollection<User> Users { get; set; }
}
public class User
{
public string UserName { get; set; }
}
public class TreeViewItemBase : INotifyPropertyChanged
{
private bool isSelected;
public bool IsSelected
{
get { return this.isSelected; }
set
{
this.isSelected = value;
NotifyPropertyChanged("IsSelected");
}
}
private bool isExpanded;
public bool IsExpanded
{
get { return this.isExpanded; }
set
{
this.isExpanded = value;
NotifyPropertyChanged("IsExpanded");
}
}


public event PropertyChangedEventHandler PropertyChanged;
public void NotifyPropertyChanged(string propName)
{
if (this.PropertyChanged != null)
this.PropertyChanged(this, new PropertyChangedEventArgs(propName));
}
}
}

如何将列表视图的所有选定项目放入选择更改事件中

Answer 1

问题出在下面的数据模板上：

<HierarchicalDataTemplate.ItemTemplate>
<DataTemplate DataType="{x:Type local:User}">
<ListView SelectionMode="Extended" SelectionChanged="ListView_SelectionChanged">
<Grid Width="150" Height="20">
<StackPanel>
<TextBlock Text="{Binding UserName}" />
</StackPanel>
</Grid>
</ListView>
</DataTemplate>
</HierarchicalDataTemplate.ItemTemplate>
</HierarchicalDataTemplate>

它为每个项目创建一个列表视图，因此只能选择一个项目。

更改 XAML 以在列表视图中显示所有用户

<Window x:Class="DemoApps.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"
mc:Ignorable="d"
Title="MainWindow" Height="350" Width="525">
<Grid>
<TreeView x:Name="TreeViewList" Loaded="TreeViewList_Loaded">
<TreeView.ItemTemplate>
<DataTemplate>
<StackPanel>
<TextBlock Text="{Binding GroupName}"/>
<ListView SelectionMode="Extended" SelectionChanged="ListView_SelectionChanged"
ItemsSource="{Binding Users}">
</ListView>
</StackPanel>
</DataTemplate>
</TreeView.ItemTemplate>
<TreeView.ItemContainerStyle>
<Style TargetType="TreeViewItem">
<Setter Property="IsSelected" Value="{Binding IsSelected}" />
<Setter Property="IsExpanded" Value="{Binding IsExpanded}" />
</Style>
</TreeView.ItemContainerStyle>
</TreeView>
</Grid>
</Window>

使用以下方法获取所选项目

private void ListView_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
var selectedItems = ((ListView) e.Source).SelectedItems;
}