GridControl.CustomUnboundColumnData Event

Enables data to be supplied to unbound columns.

Namespace: DevExpress.WinUI.Grid

Assembly: DevExpress.WinUI.Grid.v21.1.dll

Declaration

C#

public event GridColumnDataEventHandler CustomUnboundColumnData

VB.NET

Public Event CustomUnboundColumnData As GridColumnDataEventHandler

Event Data

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

Property	Description
Column	Gets the unbound column currently being processed.
ListSourceRowIndex	Gets the index of the record in the data source to which the processed item corresponds.
Row	Get a data row which contains the cell currently being processed.
Source	Gets the grid control that raised the event.

The event data class exposes the following methods:

Method	Description
GetListSourceFieldValue(Int32, String)	Returns the value of the specified cell within the specified item in the grid item source.
GetListSourceFieldValue(String)	Returns the value of the specified cell within the processed item in the grid item source.

Remarks

Unbound columns are not bound to any field in the data source. In most instances, data for unbound columns is obtained from a custom data source or is calculated based upon the values of bound columns. To provide data for unbound columns, handle the CustomUnboundColumnData event.

Example

The following code sample shows how to add an unbound column to the GridControl.

XAML

<Page
    x:Class="Unbound_Columns.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:Unbound_Columns"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:Grid="using:DevExpress.WinUI.Grid"
    mc:Ignorable="d" >
    <Page.DataContext>
        <local:ViewModel/>
    </Page.DataContext>
    <Grid>
        <Grid:GridControl Name="grid" 
                          ItemsSource="{Binding Products}" 
                          AutoGenerateColumns="False" 
                          CustomUnboundColumnData="grid_CustomUnboundColumnData">
            <Grid:GridControl.Columns>
                <Grid:GridTextColumn FieldName="ProductName"/>
                <Grid:GridTextColumn FieldName="UnitPrice"/>
                <Grid:GridTextColumn FieldName="Quantity"/>
                <Grid:GridTextColumn FieldName="Total" UnboundType="Decimal"/>
            </Grid:GridControl.Columns>
        </Grid:GridControl>
    </Grid>
</Page>

C#

void grid_CustomUnboundColumnData(object sender, DevExpress.WinUI.Grid.GridColumnDataEventArgs e) {
    if (e.IsGetData) {
        int price = Convert.ToInt32(e.GetListSourceFieldValue("UnitPrice"));
        int quantity = Convert.ToInt32(e.GetListSourceFieldValue("Quantity"));
        e.Value = price * quantity;
    }
}

VB.NET

Private Sub grid_CustomUnboundColumnData(ByVal sender As Object, ByVal e As DevExpress.WinUI.Grid.GridColumnDataEventArgs)
    If e.IsGetData Then
        Dim price As Integer = Convert.ToInt32(e.GetListSourceFieldValue("UnitPrice"))
        Dim quantity As Integer = Convert.ToInt32(e.GetListSourceFieldValue("Quantity"))
        e.Value = price * quantity
    End If
End Sub

C#

using System.Collections.Generic;
using Microsoft.UI.Xaml.Controls;
using DevExpress.Mvvm;

public class Product {
    public string ProductName { get; set; }
    public string Country { get; set; }
    public string City { get; set; }
    public double UnitPrice { get; set; }
    public int Quantity { get; set; }
}
public class ViewModel : ViewModelBase {
    public ViewModel() {
        List<Product> products = new List<Product> {
            new Product() { ProductName = "Chang", Country = "UK", City = "Cowes", UnitPrice = 19, Quantity = 10 },
            new Product() { ProductName = "Gravad lax", Country = "Italy", City = "Reggio Emilia", UnitPrice = 12.5, Quantity = 16 },
            new Product() { ProductName = "Ravioli Angelo", Country = "Brazil", City = "Rio de Janeiro", UnitPrice = 19, Quantity = 12 },
            new Product() { ProductName = "Tarte au sucre", Country = "Germany", City = "QUICK-Stop", UnitPrice = 22, Quantity = 50 },
            new Product() { ProductName = "Steeleye Stout", Country = "USA", City = "Reggio Emilia", UnitPrice = 18, Quantity = 20 },
            new Product() { ProductName = "Pavlova", Country = "Austria", City = "Graz", UnitPrice = 21, Quantity = 52 },
            new Product() { ProductName = "Longlife Tofu", Country = "USA", City = "Boise", UnitPrice = 7.75, Quantity = 120 },
            new Product() { ProductName = "Alice Mutton", Country = "Mexico", City = "México D.F.", UnitPrice = 21, Quantity = 15 },
            new Product() { ProductName = "Alice Mutton", Country = "Canada", City = "Tsawwassen", UnitPrice = 44, Quantity = 16 }
        };
        Products = products;
    }
    public List<Product> Products { get; }
}

VB.NET

Imports System.Collections.Generic
Imports Microsoft.UI.Xaml.Controls
Imports DevExpress.Mvvm

Public Class Product

    Public Property ProductName As String
    Public Property Country As String
    Public Property City As String
    Public Property UnitPrice As Double
    Public Property Quantity As Integer
End Class

Public Class ViewModel
    Inherits ViewModelBase

    Public Sub New()
        Dim products As List(Of Product) = New List(Of Product) From {
            New Product() With { .ProductName = "Chang", .Country = "UK", .City = "Cowes", .UnitPrice = 19, .Quantity = 10 },
            New Product() With { .ProductName = "Gravad lax", .Country = "Italy", .City = "Reggio Emilia", .UnitPrice = 12.5, .Quantity = 16 },
            New Product() With { .ProductName = "Ravioli Angelo", .Country = "Brazil", .City = "Rio de Janeiro", .UnitPrice = 19, .Quantity = 12 },
            New Product() With { .ProductName = "Tarte au sucre", .Country = "Germany", .City = "QUICK-Stop", .UnitPrice = 22, .Quantity = 50 },
            New Product() With { .ProductName = "Steeleye Stout", .Country = "USA", .City = "Reggio Emilia", .UnitPrice = 18, .Quantity = 20 },
            New Product() With { .ProductName = "Pavlova", .Country = "Austria", .City = "Graz", .UnitPrice = 21, .Quantity = 52 },
            New Product() With { .ProductName = "Longlife Tofu", .Country = "USA", .City = "Boise", .UnitPrice = 7.75, .Quantity = 120 },
            New Product() With { .ProductName = "Alice Mutton", .Country = "Mexico", .City = "México D.F.", .UnitPrice = 21, .Quantity = 15 },
            New Product() With { .ProductName = "Alice Mutton", .Country = "Canada", .City = "Tsawwassen", .UnitPrice = 44, .Quantity = 16 }
        }
        Products = products
    End Sub

    Public ReadOnly Property Products As List(Of Product)
End Class

For more information, refer to the following help topic: Unbound Columns.