ExplorerBarView.GroupExpandedChanged Event

Fires after the expanded state of a group has been changed.

Namespace: DevExpress.Xpf.NavBar

Assembly: DevExpress.Xpf.NavBar.v20.2.dll

NuGet Packages: DevExpress.WindowsDesktop.Wpf.NavBar, DevExpress.Wpf.Navigation

Declaration

C#

public event NavBarGroupExpandedChangedEventHandler GroupExpandedChanged

VB.NET

Public Event GroupExpandedChanged As NavBarGroupExpandedChangedEventHandler

Event Data

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

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

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. Inherited from RoutedEventArgs.
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. Inherited from RoutedEventArgs.

Remarks

Write an GroupExpandedChanged event handler to perform specific actions each time a group’s expanded state changes within the NavBarControl.

To learn more, see the Expand and Collapse Groups and Expanded Group topics.

Example

This example demonstrates how to wrap an item’s text onto several lines, if this text is too long. To accomplish this, a template of the NavBarViewBase.ItemTemplate type is created at the view level. This template contains a standard TextBlock control whose TextBlock.TextWrapping property is set to Wrap.

View Example

Application.xaml

<Application x:Class="LongNavBarItemText.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>

Window1.xaml

<Window x:Class="LongNavBarItemText.Window1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:dxn="http://schemas.devexpress.com/winfx/2008/xaml/navbar" Title="Window1" Height="300" Width="300">
    <Window.Resources>
        <DataTemplate x:Key="itemTemplate">
            <TextBlock Text="{Binding Path=Content}" TextWrapping="Wrap" />
        </DataTemplate>
    </Window.Resources>
    <dxn:NavBarControl MaxWidth="200">
        <dxn:NavBarControl.View>
            <dxn:ExplorerBarView ItemTemplate="{StaticResource itemTemplate}" />
        </dxn:NavBarControl.View>
        <dxn:NavBarControl.Groups>
            <dxn:NavBarGroup Header="Group1">
                <dxn:NavBarGroup.Items>
                    <dxn:NavBarItem Content="VeryVeryVeryVeryVeryVeryLongText1" />
                    <dxn:NavBarItem Content="VeryVeryVeryVeryVeryVeryLongText2" />
                    <dxn:NavBarItem Content="VeryVeryVeryVeryVeryVeryLongText3" />
                </dxn:NavBarGroup.Items>
            </dxn:NavBarGroup>
        </dxn:NavBarControl.Groups>
    </dxn:NavBarControl>
</Window>

Application.xaml.vb

Imports Microsoft.VisualBasic
Imports System.Windows

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

Window1.xaml.vb

Imports Microsoft.VisualBasic
Imports System.Windows

Namespace LongNavBarItemText
    ''' <summary>
    ''' Interaction logic for Window1.xaml
    ''' </summary>
    Partial Public Class Window1
        Inherits Window
        Public Sub New()
            InitializeComponent()
        End Sub
    End Class
End Namespace

Window1.xaml.cs

using System.Windows;

namespace LongNavBarItemText {
    /// <summary>
    /// Interaction logic for Window1.xaml
    /// </summary>
    public partial class Window1 : Window {
        public Window1() {
            InitializeComponent();
        }
    }
}