WPF工具包數據列可見性綁定

Question

我想將datagrid視圖列可見性與類的屬性綁定。 我正在將一個集合作爲ItemSource傳遞給網格。

我無法做到這一點。任何想法爲什麼？

Answer 1

這一個是有點棘手。問題來自DataGrid.Columns只是一個屬性而不是可視化樹的一部分。這意味着像ElementName或RelativeSource這樣的常規綁定工具將不起作用。但是，如果您覆蓋DataGrid.DataContext屬性的元數據，則可以使其正常工作。下面的示例代碼：

<Window x:Class="DataGridColumnVisibilitySample.Window1" 
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    xmlns:tk="clr-namespace:Microsoft.Windows.Controls;assembly=WPFToolkit" 
    xmlns:l="clr-namespace:DataGridColumnVisibilitySample" 
    Title="Window1" Height="300" Width="300"> 
    <Window.Resources> 
     <l:VisibilityConverter x:Key="VisibilityC" /> 
    </Window.Resources> 
    <DockPanel LastChildFill="True"> 
     <CheckBox DockPanel.Dock="Top" Margin="8" Content="Show Column B" IsChecked="{Binding ShowColumnB}" /> 
     <tk:DataGrid ItemsSource="{Binding Items}" AutoGenerateColumns="False" CanUserAddRows="False"> 
      <tk:DataGrid.Columns> 
       <tk:DataGridTextColumn Header="Column A" Binding="{Binding ColumnA}" /> 
       <tk:DataGridTextColumn Header="Column B" Binding="{Binding ColumnB}" 
             Visibility="{Binding (FrameworkElement.DataContext).ShowColumnB, 
                  RelativeSource={x:Static RelativeSource.Self}, 
                  Converter={StaticResource VisibilityC}}" /> 
       <tk:DataGridTextColumn Header="Column C" Binding="{Binding ColumnC}" /> 
      </tk:DataGrid.Columns> 
     </tk:DataGrid> 
    </DockPanel> 
</Window> 

---

using System; 
using System.Collections.Generic; 
using System.ComponentModel; 
using System.Globalization; 
using System.Linq; 
using System.Windows; 
using System.Windows.Data; 
using Microsoft.Windows.Controls; 

namespace DataGridColumnVisibilitySample 
{ 
    public partial class Window1 : INotifyPropertyChanged 
    { 
     public Window1() 
     { 
      InitializeComponent(); 
      new DataGridContextHelper(); // Initialize Helper 
      Items = Enumerable.Range(1, 3).Select(i => new MyItem {ColumnA = "A" + i, ColumnB = "B" + i, ColumnC = "C" + i}).ToList(); 
      DataContext = this; 
     } 

     public List<MyItem> Items { get; private set; } 

     private bool mShowColumnB; 
     public bool ShowColumnB 
     { 
      get { return mShowColumnB; } 
      set 
      { 
       if (mShowColumnB == value) return; 
       mShowColumnB = value; 
       if (PropertyChanged != null) 
        PropertyChanged(this, new PropertyChangedEventArgs("ShowColumnB")); 
      } 
     } 

     public event PropertyChangedEventHandler PropertyChanged; 
    } 

    public class DataGridContextHelper 
    { 
     static DataGridContextHelper() 
     { 
      FrameworkElement.DataContextProperty.OverrideMetadata(typeof(DataGrid), 
       new FrameworkPropertyMetadata(null, FrameworkPropertyMetadataOptions.Inherits, OnDataContextChanged)); 
     } 

     public static void OnDataContextChanged(DependencyObject d, DependencyPropertyChangedEventArgs e) 
     { 
      var grid = d as DataGrid; 
      if (grid == null) return; 
      foreach (var col in grid.Columns) 
       col.SetValue(FrameworkElement.DataContextProperty, e.NewValue); 
     } 
    } 

    [ValueConversion(typeof(bool), typeof(Visibility))] 
    public class VisibilityConverter : IValueConverter 
    { 
     public object Convert(object value, Type targetType, object parameter, CultureInfo culture) 
     { 
      if (value is bool && (bool)value) 
       return Visibility.Visible; 
      return Visibility.Collapsed; 
     } 

     public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture) 
     { 
      throw new NotImplementedException(); 
     } 
    } 

    public class MyItem 
    { 
     public string ColumnA { get; set; } 
     public string ColumnB { get; set; } 
     public string ColumnC { get; set; } 
    } 
} 

我創造我的解決方案來源this post by Jaime Rodriguez。

Answer 2

只要您的數據網格位於窗口，控件等中，只要它在控件模板中，這仍然不起作用