public class Gallery :
    Control

Public Class Gallery
    Inherits Control

<Window x:Class="MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="MainWindow" Height="350" Width="525"
    xmlns:dxb="http://schemas.devexpress.com/winfx/2008/xaml/bars">
    <Window.Resources>
        <DataTemplate x:Key="myItemDescriptionTemplate">
            <TextBlock Text="{Binding}" Foreground="Gray"></TextBlock>
        </DataTemplate>

    </Window.Resources>
    <Grid>
        <dxb:GalleryControl>
            <dxb:GalleryControl.Gallery>
                <dxb:Gallery ColCount="2" 
                     ItemCheckMode="None" 
                     IsGroupCaptionVisible="True"
                     IsItemCaptionVisible="True"
                     IsItemDescriptionVisible="True" 
                     ItemClick="Gallery_ItemClick"
                     FilterCaption="(click to filter groups)"
                     ItemDescriptionTemplate="{StaticResource ResourceKey=myItemDescriptionTemplate}"
                     ItemContentHorizontalAlignment="Left">
                    <dxb:Gallery.Groups>
                        <dxb:GalleryItemGroup Name="myGalleryGroup1" Caption="Misc Group">
                            <dxb:GalleryItemGroup.Items>
                                <dxb:GalleryItem Caption="Schedule" Description="Show schedule" Glyph="pack://application:,,,/Images/address-16x16.png"/>
                                <dxb:GalleryItem Caption="Roles" Description="Assign roles" Glyph="pack://application:,,,/Images/role-16x16.png"/>
                            </dxb:GalleryItemGroup.Items>
                        </dxb:GalleryItemGroup>
                        <dxb:GalleryItemGroup Name="myGalleryGroup2" Caption="Persons">
                            <dxb:GalleryItemGroup.Items>
                                <dxb:GalleryItem Caption="Employees" Glyph="pack://application:,,,/Images/employee-16x16.png"/>
                                <dxb:GalleryItem Caption="Persons" Glyph="pack://application:,,,/Images/person-16x16.png"/>
                                <dxb:GalleryItem Caption="Users" Glyph="pack://application:,,,/Images/user-16x16.png"/>
                            </dxb:GalleryItemGroup.Items>
                        </dxb:GalleryItemGroup>
                    </dxb:Gallery.Groups>
                </dxb:Gallery>
            </dxb:GalleryControl.Gallery>
        </dxb:GalleryControl>
    </Grid>
</Window>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace GalleryControl_Ex {
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window {
        public MainWindow() {
            InitializeComponent();
        }

        private void Gallery_ItemClick(object sender, DevExpress.Xpf.Bars.GalleryItemEventArgs e) {
            MessageBox.Show("The " + e.Item.Caption + " item has been clicked");
        }
    }
}

Class MainWindow 

    Private Sub Gallery_ItemClick(ByVal sender As System.Object, ByVal e As DevExpress.Xpf.Bars.GalleryItemEventArgs)
        MessageBox.Show("The " + e.Item.Caption + " item has been clicked")
    End Sub
End Class

<dxr:GalleryDropDownPopupMenu.Gallery>
    <dxb:Gallery ColCount="4" ItemDescriptionHorizontalAlignment="Left" IsItemCaptionVisible="False" IsItemDescriptionVisible="False">
        <dxb:GalleryItemGroup x:Name="grpInsertChartColumn2DCommandGroup" Caption="{Binding ConverterParameter=MenuCmd_InsertChartColumn2DCommandGroup, Converter={StaticResource stringIdConverter}, Mode=OneTime, Source={StaticResource stringIdConverter}}" IsCaptionVisible="True">

<dxr:GalleryDropDownPopupMenu.Gallery>
    <dxb:Gallery AllowFilter="False" ColCount="4" ItemDescriptionHorizontalAlignment="Left" IsItemCaptionVisible="False" IsItemDescriptionVisible="False" SizeMode="None">
        <dxb:GalleryItemGroup x:Name="grpInsertChartColumn2DCommandGroup" Caption="{Binding ConverterParameter=MenuCmd_InsertChartColumn2DCommandGroup, Converter={StaticResource stringIdConverter}, Mode=OneTime, Source={StaticResource stringIdConverter}}" IsCaptionVisible="True">

<dxr:RibbonGalleryBarItem.Gallery>
    <dxb:Gallery MinColCount="1" ColCount="5"
     ItemCheckMode="Single"

<dxb:GalleryControl.Gallery>
    <dxb:Gallery
        ColCount="3"

<dxb:GalleryControl.Gallery>
    <dxb:Gallery ColCount="2"
         ItemCheckMode="None"