Я не могу получить изменения в пользовательском интерфейсе (TextBox) при выборе элемента дерева. Когда я выбираю элемент дерева, свойство и текст должны измениться. Но этого не происходит. Свойство меняется, но текст остается прежним. Сначала я попытался вызвать изменение свойства в MainViewModel, но столкнулся с той же проблемой: свойство изменяется, но пользовательский интерфейс остается неизменным.
public class BindableSelectedItemBehavior : Behavior<TreeView>, INotifyPropertyChanged
{
MainViewModel vm = new MainViewModel();
private string _message;
public string Message
{
get
{
return _message;
}
set
{
_message = value;
OnPropertyChanged("Message");
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected void OnPropertyChanged(string propertyName)
{
if (PropertyChanged != null)
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
public object SelectedItem
{
get { return GetValue(SelectedItemProperty); }
set { SetValue(SelectedItemProperty, value); }
}
public static readonly DependencyProperty SelectedItemProperty =
DependencyProperty.Register(nameof(SelectedItem), typeof(object), typeof(BindableSelectedItemBehavior), new UIPropertyMetadata(null, OnSelectedItemChanged));
private static void OnSelectedItemChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
{
var item = e.NewValue as TreeViewItem;
if (item != null)
{
item.SetValue(TreeViewItem.IsSelectedProperty, true);
}
}
protected override void OnAttached()
{
base.OnAttached();
AssociatedObject.SelectedItemChanged += OnTreeViewSelectedItemChanged;
}
protected override void OnDetaching()
{
base.OnDetaching();
if (AssociatedObject != null)
{
AssociatedObject.SelectedItemChanged -= OnTreeViewSelectedItemChanged;
}
}
private void OnTreeViewSelectedItemChanged(object sender, RoutedPropertyChangedEventArgs<object> e)
{
SelectedItem = e.NewValue;
string name = GetName((Item)SelectedItem);
Message = "edgddgdgdg";
}
public string GetName(Item item)
{
string circ = item.Name;
return circ;
}
}
}
<UserControl x:Class="WpfApp3.TreeViewTextChange"
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"
xmlns:local="clr-namespace:WpfApp3"
xmlns:vm="clr-namespace:WpfApp3.ViewModel"
mc:Ignorable="d"
d:DesignHeight="450" d:DesignWidth="800">
<UserControl.DataContext>
<vm:BindableSelectedItemBehavior/>
</UserControl.DataContext>
<Grid>
<TextBox Grid.Row="1" Grid.Column="2" Text="{Binding Path=Message, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" Background="Aqua" Width="200" Height="50"/>
</Grid>
</UserControl>
Использовал отладчик - свойство изменяется, но не изменяется текстовое поле в UserControl. Моя MainViewModel
class MainViewModel : BindableBase
{
MainModel mainModel = new MainModel();
private ICollectionView root;
public MainViewModel()
{
OpenSth = new DelegateCommand(DisplayItemTree);
ShowCheck = new DelegateCommand(ShowCheckedItemsCommand);
Sth = new DelegateCommand(Changetext);
TextChengedCommand = new DelegateCommand<object>(textChange);
}
public ICommand OpenSth { get; }
public ICommand ShowCheck { get; }
public ICommand Sth { get; }
public ICommand TextChengedCommand { get; }
private void textChange(object obj)
{
var str = obj as string;
}
public void DisplayItemTree()
{
var itemTree = mainModel.GetItemsTree();
Root = CollectionViewSource.GetDefaultView(itemTree);
Root.Filter = new Predicate<object>((item) =>
{
var realItem = (Item)item;
return true;
});
Root.Refresh();
}
public ICollectionView Root
{
get => root;
set => SetProperty(ref root, value);
}
public void ShowCheckedItemsCommand()
{
var str = new StringBuilder();
List<Item> items = mainModel.FindCheckedItem();
if (items.Count == 0)
{
str.Append("No selected items");
}
else
{
foreach (var item in items)
{
str.Append(item.Name);
}
}
MessageBox.Show(str.ToString());
}
private string _name;
public string TextText
{
get { return _name; }
set
{
_name = value;
RaisePropertyChanged("TextText");
}
}
public void Changetext()
{
TextText = "dggg";
}
}
}
И код xaml
<Window x:Class="WpfApp3.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:WpfApp3"
xmlns:beh="clr-namespace:WpfApp3.ViewModel"
xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
xmlns:ii="http://schemas.microsoft.com/expression/2010/interactivity"
xmlns:prism="http://www.codeplex.com/prism"
mc:Ignorable="d"
xmlns:vm="clr-namespace:WpfApp3.ViewModel"
xmlns:bh="clr-namespace:WpfApp3.ViewModel"
Title="MainWindow" Height="450" Width="800">
<Window.DataContext>
<vm:MainViewModel/>
</Window.DataContext>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="50"/>
<ColumnDefinition Width="200"/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition/>
<RowDefinition/>
</Grid.RowDefinitions>
<DockPanel Grid.Column="1" Grid.Row="0" Grid.RowSpan="2">
<TextBox x:Name="searchBox" DockPanel.Dock="Top" Height="30" VerticalAlignment="Top" BorderBrush="Black" BorderThickness="1" Text="{Binding SearchText}">
<ii:Interaction.Triggers>
<ii:EventTrigger EventName="TextChenged">
<ii:InvokeCommandAction Command="{Binding TextChengedCommand}" CommandParameter="{Binding ElementName=searchBox, Path=Text}"/>
</ii:EventTrigger>
</ii:Interaction.Triggers>
</TextBox>
<DockPanel DockPanel.Dock="Bottom">
<Button Content="Get TreeView" Command="{Binding OpenSth}" Width="100"/>
<Button Content="Show Check Item" Command="{Binding ShowCheck}" Width="100"/>
</DockPanel>
<TreeView BorderBrush="Black" BorderThickness="1" ItemsSource="{Binding Root}">
<i:Interaction.Behaviors>
<beh:BindableSelectedItemBehavior SelectedItem="{Binding SelectedNode, Mode=TwoWay}"/>
</i:Interaction.Behaviors>
<TreeView.ItemTemplate>
<HierarchicalDataTemplate ItemsSource="{Binding Sub}">
<DockPanel>
<CheckBox IsChecked="{Binding CheckedItem}" Margin="0 8 0 8" VerticalAlignment="Center" DockPanel.Dock="Left"/>
<TextBlock Text="{Binding Name}" VerticalAlignment="Center" DockPanel.Dock="Right"/>
</DockPanel>
</HierarchicalDataTemplate>
</TreeView.ItemTemplate>
</TreeView>
</DockPanel>
<DataGrid AutoGenerateColumns="False" Height="210" HorizontalContentAlignment="Left" Name="DataGrid" VerticalAlignment="Top" Grid.Column="2" Grid.Row="0" Margin="0,0,0,0" ItemsSource="{Binding ListOfCircuets}">
<DataGrid.Columns>
<DataGridTextColumn Binding="{Binding Length}" MinWidth="50"/>
<DataGridTextColumn Binding="{Binding dU}" MinWidth="50"/>
<DataGridTextColumn Binding="{Binding Cable}" MinWidth="50"/>
<DataGridTextColumn Binding="{Binding I}" MinWidth="50"/>
</DataGrid.Columns>
</DataGrid>
<TextBox Grid.Row="1" Grid.Column="2" Text="{Binding TextText, Mode=TwoWay}" Background="Aqua" Width="200" Height="50"/>
<Button Content="Show Check Item" Command="{Binding Sth}" Width="100"/>
<local:TreeViewTextChange Grid.Row="1" Grid.Column="2"></local:TreeViewTextChange>
</Grid>
</Window>