Hide column using data annotations in WPF

Question

I have a grid in WPF, auto-generating columns. How can I dynamically hide columns using data annotations?

I was thinking about having a property in my model to indicate if the column is visible, but I'm not sure how to do it.

My gridded model:

public class Template { public string County { get; set; } public string Operator { get; set; } public string Field { get; set; } } 

Answer 1

Here is an example that uses attributes to hide columns. It uses an attached property to handle an AutoGeneratingColumn event.

HideColumnIfAutoGenerated.cs - Attribute

 namespace AutoHideColumn { public class HideColumnIfAutoGenerated : System.Attribute { public HideColumnIfAutoGenerated() { } } } 

DataGridExtension.cs - attached property

 using System.ComponentModel; using System.Windows; using System.Windows.Controls; namespace AutoHideColumn { public static class DataGridExtension { public static readonly DependencyProperty HideAnnotatedColumnsProperty = DependencyProperty.RegisterAttached( "HideAnnotatedColumns", typeof(bool), typeof(DataGridExtension), new UIPropertyMetadata(false, OnHideAnnotatedColumns)); public static bool GetHideAnnotatedColumns(DependencyObject d) { return (bool)d.GetValue(HideAnnotatedColumnsProperty); } public static void SetHideAnnotatedColumns(DependencyObject d, bool value) { d.SetValue(HideAnnotatedColumnsProperty, value); } private static void OnHideAnnotatedColumns(DependencyObject d, DependencyPropertyChangedEventArgs e) { bool hideAnnotatedColumns = (bool)e.NewValue; DataGrid dataGrid = d as DataGrid; if (hideAnnotatedColumns) { dataGrid.AutoGeneratingColumn += dataGrid_AutoGeneratingColumn; } else { dataGrid.AutoGeneratingColumn -= dataGrid_AutoGeneratingColumn; } } private static void dataGrid_AutoGeneratingColumn(object sender, DataGridAutoGeneratingColumnEventArgs e) { PropertyDescriptor propertyDescriptor = e.PropertyDescriptor as PropertyDescriptor; if (propertyDescriptor != null) { foreach (var item in propertyDescriptor.Attributes) { if (item.GetType() == typeof(HideColumnIfAutoGenerated)) { e.Cancel = true; } } } } } } 

Xaml

 <Window x:Class="AutoHideColumn.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:local="clr-namespace:AutoHideColumn" Title="MainWindow" Height="350" Width="525"> <Grid> <Grid.RowDefinitions> <RowDefinition Height="*"/> <RowDefinition Height="*"/> </Grid.RowDefinitions> <DataGrid Name="dg" local:DataGridExtension.HideAnnotatedColumns="True"> </DataGrid> <DataGrid Grid.Row="1" Name="dg1"> </DataGrid> </Grid> </Window> 

CodeBehind

 using System.Collections.Generic; using System.Windows; namespace AutoHideColumn { /// <summary> /// Interaction logic for MainWindow.xaml /// </summary> public partial class MainWindow : Window { public MainWindow() { InitializeComponent(); this.dg.ItemsSource = new List<Customer>(); this.dg1.ItemsSource = new List<Customer>(); } } public class Customer { [HideColumnIfAutoGenerated()] public int ID { get; set; } public string Name { get; set; } } } 

Answer 2

try it

 public partial class MainWindow : Window { private List<string> visibleColumns; public MainWindow() { InitializeComponent(); InitializeList(); visibleColumns = GetVisibleColumns(); dg.AutoGeneratingColumn += dg_AutoGeneratingColumn; dg.ItemsSource = Templates; } void dg_AutoGeneratingColumn(object sender, DataGridAutoGeneratingColumnEventArgs e) { if(!visibleColumns.Contains(e.Column.Header.ToString())) e.Column.Visibility=Visibility.Collapsed; } List<string> GetVisibleColumns() { return typeof(Template).GetProperties() .Where(p => p.GetCustomAttributes(typeof(Visible), true) .Where(ca => ((Visible)ca).IsVisible).Any() ).Select(s => s.Name).ToList(); } private void InitializeList() { Templates = new List<Template>(); Templates.Add(new Template { County = "abc", Operator = "123", Field = "xyz" }); Templates.Add(new Template { County = "abc", Operator = "123", Field = "xyz" }); Templates.Add(new Template { County = "abc", Operator = "123", Field = "xyz" }); Templates.Add(new Template { County = "abc", Operator = "123", Field = "xyz" }); } public List<Template> Templates { get; set; } } 

Template Class

 public class Template { [Visible(false)] public string County { get; set; } [Visible(true)] public string Operator { get; set; } [Visible(true)] public string Field { get; set; } } 

Visible attribute

 public class Visible : Attribute { public Visible(bool isVisible) { IsVisible = isVisible; } public bool IsVisible { get; set; } } 

> Xaml

 <Grid> <DataGrid AutoGenerateColumns="True" x:Name="dg"/> </Grid> 

Answer 3

this will certainly be the most simplified workaround that comes close to data annotation: omit the getter and setter.

 public class Template { public string County { get; set; } public string Operator { get; set; } public string Field; //This is now a field and not a property-> invisible in datadrid } 

Answer 4

Attributes cannot be changed at run time, so you cannot dynamically hide columns using data annotations. But you can dynamically hide columns. Here is an example that demonstrates it.

Xaml

 <Grid> <Grid.RowDefinitions> <RowDefinition Height="Auto"/> <RowDefinition Height="Auto"/> <RowDefinition Height="*"/> </Grid.RowDefinitions> <DataGrid ItemsSource="{Binding AutoGenerateColumnDetails}" CanUserAddRows="False" CanUserDeleteRows="False"> </DataGrid> <Button Grid.Row="1" Content="Refresh" Click="Button_Click" HorizontalAlignment="Left" Margin="5"/> <DataGrid Name="dg" Grid.Row="2" ItemsSource="{Binding TemplateList}" AutoGeneratingColumn="dg_AutoGeneratingColumn"> </DataGrid> </Grid> 

Code for

 using System.Collections.Generic; using System.Linq; using System.Windows; using System.Windows.Controls; namespace AutoHideDGColumn { /// <summary> /// Interaction logic for MainWindow.xaml /// </summary> public partial class MainWindow : Window { private ViewModel _ViewModel = null; public MainWindow() { InitializeComponent(); _ViewModel = new ViewModel(); this.DataContext = _ViewModel; } private void dg_AutoGeneratingColumn(object sender, DataGridAutoGeneratingColumnEventArgs e) { if (_ViewModel.AutoGenerateColumnDetails.Where(d => d.HideColumn == true).Select(d => d.PropertyName).ToList().Contains(e.PropertyName)) e.Cancel = true; } private void Button_Click(object sender, RoutedEventArgs e) { // Reset to trigger AutoGeneratingColumn event this.dg.AutoGenerateColumns = false; this.dg.AutoGenerateColumns = true; } } public class ViewModel { private List<Template> _TemplateList; public List<Template> TemplateList { get { return _TemplateList; } set { _TemplateList = value; } } private List<AutoGenerateColumnDetail> _AutoGenerateColumnDetails; public List<AutoGenerateColumnDetail> AutoGenerateColumnDetails { get { return _AutoGenerateColumnDetails; } set { _AutoGenerateColumnDetails = value; } } public ViewModel() { AutoGenerateColumnDetails = typeof(Template).GetProperties().Select(p => new AutoGenerateColumnDetail() { PropertyName = p.Name }).ToList(); TemplateList = new List<Template>() { new Template() { County = "Count1", Field = "Field1", Operator = "Operator1"}, new Template() { County = "Count2", Field = "Field2", Operator = "Operator2"}, new Template() { County = "Count3", Field = "Field2", Operator = "Operator3"}, }; } } public class Template { public string County { get; set; } public string Operator { get; set; } public string Field { get; set; } } public class AutoGenerateColumnDetail { public string PropertyName { get; set; } public bool HideColumn { get; set; } } }