DataControlBase.ColumnsPopulated Event

OBSOLETE

Use the AutoGeneratedColumns event instead

Occurs after the columns have been automatically generated.

Namespace: DevExpress.Xpf.Grid

Assembly: DevExpress.Xpf.Grid.v18.2.Core.dll

Declaration

C#

[Obsolete("Use the AutoGeneratedColumns event instead")]
[Browsable(false)]
public event RoutedEventHandler ColumnsPopulated

VB.NET

<Obsolete("Use the AutoGeneratedColumns event instead")>
<Browsable(False)>
Public Event ColumnsPopulated As RoutedEventHandler

Event Data

The ColumnsPopulated event's data class is RoutedEventArgs. The following properties provide information specific to this event:

Property	Description
Handled	Gets or sets a value that indicates the present state of the event handling for a routed event as it travels the route.
OriginalSource	Gets the original reporting source as determined by pure hit testing, before any possible Source adjustment by a parent class.
RoutedEvent	Gets or sets the RoutedEvent associated with this RoutedEventArgs instance.
Source	Gets or sets a reference to the object that raised the event.

The event data class exposes the following methods:

Method	Description
InvokeEventHandler(Delegate, Object)	When overridden in a derived class, provides a way to invoke event handlers in a type-specific way, which can increase efficiency over the base implementation.
OnSetSource(Object)	When overridden in a derived class, provides a notification callback entry point whenever the value of the Source property of an instance changes.

Remarks

If the grid’s DataControlBase.AutoPopulateColumns option is enabled and the GridControl.Columns collection is empty, binding the grid to a data source automatically generates columns for all data source fields. After all columns have been created and added to the GridControl.Columns collection, the grid fires the ColumnsPopulated event. Handle this event to specify column settings (e.g. assign column editors, hide individual columns, etc.).

The ColumnsPopulated event is not raised if the grid columns are explicitly specified (for instance, in the XAML file), or the DataControlBase.AutoPopulateColumns property is set to false.

Example

The following example shows how to customize automatically generated columns.In this example, the ColumnsPopulated event is handled to hide the 'ID' column, and specify the sorting order of the first visible column.Starting with version 2013 vol 1 the GridControl.ColumnsPopulated event is marked as obsolete. The GridControl.AutoGeneratedColumns event should be used instead. Moreover, in 13.1, this example includes two ways for setting templates in code-behind.

Note

A complete sample project is available at https://github.com/DevExpress-Examples/how-to-customize-automatically-generated-columns-e2019.

Window1.xaml

<Window x:Class="E2019.Window1"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:dxg="http://schemas.devexpress.com/winfx/2008/xaml/grid"
        xmlns:dxe="http://schemas.devexpress.com/winfx/2008/xaml/editors"
        xmlns:local="clr-namespace:E2019"
        Title="Window" Height="200" Width="470">
    <Window.Resources>
        <local:IssueTypeForegroundConverter x:Key="IssueTypeForegroundConverter"/>
        <DataTemplate x:Key="IssueNameTemplate">
            <dxe:TextEdit x:Name="PART_Editor" Foreground="Blue"/>
        </DataTemplate>
        <DataTemplate x:Key="IssueTypeTemplate">
            <dxe:TextEdit x:Name="PART_Editor" Foreground="{Binding Path=Value, Converter={StaticResource IssueTypeForegroundConverter}}"/>
        </DataTemplate>
    </Window.Resources>
    <Grid>
       <dxg:GridControl x:Name="grid" AutoGenerateColumns="AddNew" AutoGeneratedColumns="OnColumnsGenerated">
          <dxg:GridControl.View>
             <dxg:TableView Name="tableView1" AutoWidth="True" />
          </dxg:GridControl.View>
       </dxg:GridControl>
    </Grid>
</Window>

Window1.xaml.cs

using System.Collections.Generic;
using System.Windows;
using System.Windows.Documents;
using DevExpress.Xpf.Grid;
using System.Windows.Data;
using System.Windows.Media;

namespace E2019 {
    public partial class Window1 : Window {
        public Window1() {
            InitializeComponent();
            grid.ItemsSource = IssueList.GetData();
        }
        private void OnColumnsGenerated(object sender, RoutedEventArgs e) {
            foreach (GridColumn column in grid.Columns) {
                switch (column.FieldName) {
                    case "IssueName":
                        column.CellTemplate = Application.Current.MainWindow.Resources["IssueNameTemplate"] as DataTemplate;
                        column.SortOrder = DevExpress.Data.ColumnSortOrder.Ascending;
                        break;
                    case "IssueType":
                        column.CellTemplate = Application.Current.MainWindow.Resources["IssueTypeTemplate"] as DataTemplate;
                        break;
                    case "ID":
                        column.Visible = false;
                        break;
                }
            }
        }
        public class IssueList {
            static public List<IssueDataObject> GetData() {
                List<IssueDataObject> data = new List<IssueDataObject>();
                data.Add(new IssueDataObject() {
                    ID = 0,
                    IssueName = "Transaction History", IssueType = "Bug", IsPrivate = true
                });
                data.Add(new IssueDataObject() {
                    ID = 1,
                    IssueName = "Ledger: Inconsistency", IssueType = "Bug", IsPrivate = false
                });
                data.Add(new IssueDataObject() {
                    ID = 2,
                    IssueName = "Data Import", IssueType = "Request", IsPrivate = false
                });
                data.Add(new IssueDataObject() {
                    ID = 3,
                    IssueName = "Data Archiving", IssueType = "Request", IsPrivate = true
                });
                return data;
            }
        }
        public class IssueDataObject {
            public int ID { get; set; }
            public string IssueName { get; set; }
            public string IssueType { get; set; }
            public bool IsPrivate { get; set; }
        }
    }

    public class IssueTypeForegroundConverter : IValueConverter {
        public object Convert(object value, System.Type targetType, object parameter, System.Globalization.CultureInfo culture) {
            if (value == null)
                return null;

            string issueType = value.ToString();
            if (issueType == "Bug")
                return new SolidColorBrush(Colors.Red);

            return new SolidColorBrush(Colors.Black);
        }

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

}

Application.xaml

<Application x:Class="DXGrid_ColumnsPopulatedEvent.App" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" StartupUri="Window1.xaml">
    <Application.Resources>

    </Application.Resources>
</Application>

Application.xaml.vb

Imports System
Imports System.Collections.Generic
Imports System.Configuration
Imports System.Data
Imports System.Linq
Imports System.Windows

Namespace DXGrid_ColumnsPopulatedEvent
    ''' <summary>
    ''' Interaction logic for App.xaml
    ''' </summary>
    Partial Public Class App
        Inherits Application

    End Class
End Namespace

Window1.xaml.vb

Imports System.Collections.Generic
Imports System.Windows
Imports System.Windows.Documents
Imports DevExpress.Xpf.Grid
Imports System.Windows.Data
Imports System.Windows.Media

Namespace E2019
    Partial Public Class Window1
        Inherits Window

        Public Sub New()
            InitializeComponent()
            grid.ItemsSource = IssueList.GetData()
        End Sub
        Private Sub OnColumnsGenerated(ByVal sender As Object, ByVal e As RoutedEventArgs)
            For Each column As GridColumn In grid.Columns
                Select Case column.FieldName
                    Case "IssueName"
                        column.CellTemplate = TryCast(Application.Current.MainWindow.Resources("IssueNameTemplate"), DataTemplate)
                        column.SortOrder = DevExpress.Data.ColumnSortOrder.Ascending
                    Case "IssueType"
                        column.CellTemplate = TryCast(Application.Current.MainWindow.Resources("IssueTypeTemplate"), DataTemplate)
                    Case "ID"
                        column.Visible = False
                End Select
            Next column
        End Sub
        Public Class IssueList
            Public Shared Function GetData() As List(Of IssueDataObject)
                Dim data As New List(Of IssueDataObject)()
                data.Add(New IssueDataObject() With {.ID = 0, .IssueName = "Transaction History", .IssueType = "Bug", .IsPrivate = True})
                data.Add(New IssueDataObject() With {.ID = 1, .IssueName = "Ledger: Inconsistency", .IssueType = "Bug", .IsPrivate = False})
                data.Add(New IssueDataObject() With {.ID = 2, .IssueName = "Data Import", .IssueType = "Request", .IsPrivate = False})
                data.Add(New IssueDataObject() With {.ID = 3, .IssueName = "Data Archiving", .IssueType = "Request", .IsPrivate = True})
                Return data
            End Function
        End Class
        Public Class IssueDataObject
            Public Property ID() As Integer
            Public Property IssueName() As String
            Public Property IssueType() As String
            Public Property IsPrivate() As Boolean
        End Class
    End Class

    Public Class IssueTypeForegroundConverter
        Implements IValueConverter

        Public Function Convert(ByVal value As Object, ByVal targetType As System.Type, ByVal parameter As Object, ByVal culture As System.Globalization.CultureInfo) As Object Implements IValueConverter.Convert
            If value Is Nothing Then
                Return Nothing
            End If

            Dim issueType As String = value.ToString()
            If issueType = "Bug" Then
                Return New SolidColorBrush(Colors.Red)
            End If

            Return New SolidColorBrush(Colors.Black)
        End Function

        Public Function ConvertBack(ByVal value As Object, ByVal targetType As System.Type, ByVal parameter As Object, ByVal culture As System.Globalization.CultureInfo) As Object Implements IValueConverter.ConvertBack
            Throw New System.NotImplementedException()
        End Function
    End Class

End Namespace