How to: Select Templates Based on Custom Logic

• Jun 07, 2019
• 3 minutes to read

This example demonstrates how to use DataRowTemplateSelector to apply different templates to even and odd data rows.

Use the How to dynamically select a row details template with DataTemplateSelector example if you want to dynamically select Row Details Templates.

Note

A complete sample project is available at https://github.com/DevExpress-Examples/how-to-select-templates-based-on-custom-logic-e1667.

Window1.xaml.vb

Imports System
Imports System.Collections.Generic
Imports System.Linq
Imports System.Windows

Namespace DXGrid_TemplateSelector

    Partial Public Class Window1
        Inherits Window

        Public Sub New()
            InitializeComponent()
            grid.ItemsSource = IssueDataObject.GetData()
        End Sub
    End Class

    Public Class IssueDataObject
        Public Property IssueName() As String
        Public Shared Function GetData() As List(Of IssueDataObject)
            Dim data As New List(Of IssueDataObject)()
            data.Add(New IssueDataObject() With {.IssueName = "Transaction History"})
            data.Add(New IssueDataObject() With {.IssueName = "Ledger: Inconsistency"})
            data.Add(New IssueDataObject() With {.IssueName = "Data Import"})
            data.Add(New IssueDataObject() With {.IssueName = "Data Archiving"})
            Return data
        End Function
    End Class
End Namespace

RowTemplateSelector.vb

Imports DevExpress.Xpf.Grid
Imports System
Imports System.Linq
Imports System.Windows
Imports System.Windows.Controls

Namespace DXGrid_TemplateSelector
    Public Class RowTemplateSelector
        Inherits DataTemplateSelector

        Public Property EvenRowTemplate() As DataTemplate
        Public Property OddRowTemplate() As DataTemplate
        Public Overrides Function SelectTemplate(ByVal item As Object, ByVal container As DependencyObject) As DataTemplate
            Dim row As RowData = TryCast(item, RowData)
            If row IsNot Nothing Then
                Return If(row.EvenRow, EvenRowTemplate, OddRowTemplate)
            End If
            Return MyBase.SelectTemplate(item, container)
        End Function
    End Class
End Namespace

Window1.xaml

<Window x:Class="DXGrid_TemplateSelector.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:local="clr-namespace:DXGrid_TemplateSelector"
        Width="300"
        Height="300"
        Title="Window1">

    <Window.Resources>
        <DataTemplate x:Key="evenRowTemplate">
            <Border Margin="1"
                    Background="Blue"
                    CornerRadius="5">
                <TextBlock Margin="5"
                           Foreground="White"
                           Text="{Binding DataContext.IssueName}" />
            </Border>
        </DataTemplate>
        <DataTemplate x:Key="oddRowTemplate">
            <Border Margin="1"
                    Background="Orange"
                    CornerRadius="5">
                <TextBlock Margin="5"
                           Foreground="White"
                           Text="{Binding DataContext.IssueName}" />
            </Border>
        </DataTemplate>
        <local:RowTemplateSelector x:Key="rowTemplateSelector"
                                   EvenRowTemplate="{StaticResource evenRowTemplate}"
                                   OddRowTemplate="{StaticResource oddRowTemplate}" />
    </Window.Resources>

    <Grid>
        <dxg:GridControl x:Name="grid"
                         AutoGenerateColumns="AddNew">
            <dxg:GridControl.View>
                <dxg:TableView AutoWidth="True"
                               DataRowTemplateSelector="{StaticResource rowTemplateSelector}"
                               NavigationStyle="None"
                               ShowColumnHeaders="False"
                               ShowGroupPanel="False"
                               ShowHorizontalLines="False" />
            </dxg:GridControl.View>
        </dxg:GridControl>
    </Grid>
</Window>

Window1.xaml.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows;

namespace DXGrid_TemplateSelector {

    public partial class Window1 : Window {
        public Window1() {
            InitializeComponent();
            grid.ItemsSource = IssueDataObject.GetData();
        }
    }

    public class IssueDataObject {
        public string IssueName { get; set; }
        public static List<IssueDataObject> GetData() {
            List<IssueDataObject> data = new List<IssueDataObject>();
            data.Add(new IssueDataObject() { IssueName = "Transaction History" });
            data.Add(new IssueDataObject() { IssueName = "Ledger: Inconsistency" });
            data.Add(new IssueDataObject() { IssueName = "Data Import" });
            data.Add(new IssueDataObject() { IssueName = "Data Archiving" });
            return data;
        }
    }
}

RowTemplateSelector.cs

using DevExpress.Xpf.Grid;
using System;
using System.Linq;
using System.Windows;
using System.Windows.Controls;

namespace DXGrid_TemplateSelector
{
    public class RowTemplateSelector : DataTemplateSelector
    {
        public DataTemplate EvenRowTemplate { get; set; }
        public DataTemplate OddRowTemplate { get; set; }
        public override DataTemplate SelectTemplate(object item, DependencyObject container) {
            RowData row = item as RowData;
            if (row != null)
                return row.EvenRow ? EvenRowTemplate : OddRowTemplate;
            return base.SelectTemplate(item, container);
        }
    }
}