ASPxNavBar.ExpandedChanged Event

Fires on the server side after a group’s expansion state has been changed.

Namespace: DevExpress.Web

Assembly: DevExpress.Web.v19.2.dll

Declaration

C#

public event NavBarGroupEventHandler ExpandedChanged

VB.NET

Public Event ExpandedChanged As NavBarGroupEventHandler

Event Data

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

Property	Description
Group	Gets a group for which the event is fired.

Remarks

Write an ExpandedChanged event handler to perform specific actions on the server side each time after a group’s expansion state has been changed. You can use the event parameter’s NavBarGroupEventArgs.Group property to identify the group which has been expanded or collapsed.

Example

The full sample code can be obtained by using the How to create and load a NavBar group content on a callback example.

C#

public partial class ASPxperience_LoadOnCallback : System.Web.UI.Page {
     protected void LoadGroupContent(NavBarGroup group) {
         Control control = null;
         if(group.Expanded && group.ContentTemplate == null) {
             switch(group.Name) {
                 case "Group1":
                 case "Group2":
                     control = LoadControl("UserControl.ascx");
                     break;
             }
             group.ContentTemplate = control as ITemplate;
         }
     }
     protected void LoadExpandedGroups() {
         for(int i = 0; i < ASPxNavBar1.Groups.Count; i++)
             LoadGroupContent(ASPxNavBar1.Groups[i]);
     }

     protected void Page_Load(object sender, EventArgs e) {
         LoadExpandedGroups();
     }
     protected void ASPxNavBar1_ExpandedChanged(object source, 
     DevExpress.Web.NavBarGroupEventArgs e) {
         LoadGroupContent(e.Group);
     }
}

VB.NET

Partial Public Class ASPxperience_LoadOnCallback
    Inherits System.Web.UI.Page
     Protected Sub LoadGroupContent(ByVal group As NavBarGroup)
         Dim control As Control = Nothing
         If group.Expanded AndAlso group.ContentTemplate Is Nothing Then
             Select Case group.Name
                 Case "Group1", "Group2"
                     control = LoadControl("UserControl.ascx")
             End Select
             group.ContentTemplate = TryCast(control, ITemplate)
         End If
     End Sub
     Protected Sub LoadExpandedGroups()
         For i As Integer = 0 To ASPxNavBar1.Groups.Count - 1
             LoadGroupContent(ASPxNavBar1.Groups(i))
         Next i
     End Sub

     Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
         LoadExpandedGroups()
     End Sub
     Protected Sub ASPxNavBar1_ExpandedChanged(ByVal source As Object, ByVal e As DevExpress.Web.NavBarGroupEventArgs)
         LoadGroupContent(e.Group)
     End Sub
End Class