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.NET and JavaScript UI Controls
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MaximumDropDownItems Property (UltraNavigationBarLocationSettings)

Gets/sets the maximum number of items that are visible in the dropdown list which appears when the associated UltraNavigationBarLocation is expanded.
Syntax
'Declaration
 
Public Property MaximumDropDownItems As Integer
public int MaximumDropDownItems {get; set;}
Exceptions
ExceptionDescription
System.ArgumentOutOfRangeExceptionThrown when the property is set to a value that is less than -1. Note that a value of -1 is valid, and signifies that the property is not specifically set at this level of the property resolution hierarchy.
Remarks

When a location's dropdown button is clicked by the end user, it becomes the ExpandedLocation. A dropdown list is displayed, which contains the visible members of its Locations collection. The MaximumDropDownItems property determines how many of these child locations are displayed at any given time. When the number of visible child locations exceeds the value of the MaximumDropDownItems property, a vertical scrollbar is displayed to provide access to the non-visible items.

The default value, -1, signifies that the property is not specifically set at this level of the property resolution hierarchy, and that the actual value will be determined at a higher level. A value of zero signifies that the number of items displayed will only be restricted by the size of the display.

Note: Setting the property on the instance returned from the LocationSettings property affects all UltraNavigationBarLocation displayed by the control that do not have a more specific setting; setting the property on the instance returned from the Settings property affects only that instance, and overrides the setting at the control level.

Example
The following code sample demonstrates how to configure the UltraNavigationBar for navigating the local computer's file system.

Imports System
Imports System.Drawing
Imports System.IO
Imports System.Collections.Generic
Imports System.ComponentModel
Imports Infragistics.Shared
Imports Infragistics.Win
Imports Infragistics.Win.Misc
Imports Infragistics.Win.Misc.UltraWinNavigationBar
Imports Infragistics.Win.UltraWinTree

Public Class FileSystemSupport

    Private Const PATH_SEPARATOR As String = "\"    
    Private navigationBar As UltraNavigationBar = Nothing
    Private tree As UltraTree = Nothing

    Public Sub New(ByVal navigationBar As UltraNavigationBar, ByVal tree As UltraTree)

        MyBase.New()

        '  Store references to the UltraNavigationBar and UltraTree
        Me.navigationBar = navigationBar
        Me.tree = tree

        '  Create the images we will use for the drives, folders, etc.
        Me.CreateImages()

        '  Assign the folder image to the general node and location appearances.
        Me.navigationBar.LocationSettings.Appearance.Image = Me.GetImage(Images.Folder)
        Me.tree.Override.NodeAppearance.Image = Me.GetImage(Images.Folder)

        '  Synchronize the ImageSize properties for each control.
        Me.tree.Override.ImageSize = Me.navigationBar.ImageSizeResolved

        '  Since we are lazily populating the nodes collections,
        '  show the expansion indicator initially for all nodes.
        Me.tree.Override.ShowExpansionIndicator = ShowExpansionIndicator.CheckOnExpand

        '  Set any additional properties on the UltraTree.
        Me.tree.ScrollBounds = ScrollBounds.ScrollToFill
        Me.tree.Override.SelectionType = SelectType.Single
        Me.tree.HideSelection = False

        '  Add an action button so the end user can refresh the directories.
        Me.navigationBar.ActionButtons.Clear()
        Dim actionButton As UltraNavigationBarActionButton = Me.navigationBar.ActionButtons.Add("Refresh")
        actionButton.Settings.Appearance.Image = Me.GetImage(Images.Refresh)

        '  Restrict the width of the location's text button so very long
        '  directory names don't hog up all the space.
        Me.navigationBar.LocationSettings.MaximumTextButtonWidth = 100

        '  Restrict the number of items that can appear in the locations dropdown list.
        Me.navigationBar.LocationSettings.MaximumDropDownItems = 10

        '  Register as a listener for the events of interest
        Me.HookEvents(True)
    End Sub

    Private Sub HookEvents(ByVal hook As Boolean)

        If (hook) Then

            '  NavigationBar
            AddHandler Me.navigationBar.InitializeLocations, AddressOf Me.OnNavigationBarInitializeLocations
            AddHandler Me.navigationBar.SelectedLocationChanged, AddressOf Me.OnNavigationBarSelectedLocationChanged
            AddHandler Me.navigationBar.ActionButtonClicked, AddressOf Me.OnNavigationBarActionButtonClicked
            AddHandler Me.navigationBar.ActionButtonToolTipDisplaying, AddressOf Me.OnNavigationBarActionButtonToolTipDisplaying

            '  Tree
            AddHandler Me.tree.BeforeExpand, AddressOf Me.OnTreeBeforeExpand
            AddHandler Me.tree.AfterActivate, AddressOf Me.OnTreeAfterActivate

        Else

            '  NavigationBar
            RemoveHandler Me.navigationBar.InitializeLocations, AddressOf Me.OnNavigationBarInitializeLocations
            RemoveHandler Me.navigationBar.SelectedLocationChanged, AddressOf Me.OnNavigationBarSelectedLocationChanged
            RemoveHandler Me.navigationBar.ActionButtonClicked, AddressOf Me.OnNavigationBarActionButtonClicked
            RemoveHandler Me.navigationBar.ActionButtonToolTipDisplaying, AddressOf Me.OnNavigationBarActionButtonToolTipDisplaying

            '  Tree
            RemoveHandler Me.tree.BeforeExpand, AddressOf Me.OnTreeBeforeExpand
            RemoveHandler Me.tree.AfterActivate, AddressOf Me.OnTreeAfterActivate

        End If

    End Sub

End Class
using System;
using System.Drawing;
using System.IO;
using System.Collections.Generic;
using System.ComponentModel;
using Infragistics.Shared;
using Infragistics.Win;
using Infragistics.Win.Misc;
using Infragistics.Win.Misc.UltraWinNavigationBar;
using Infragistics.Win.UltraWinTree;

    public class FileSystemSupport
    {
        private const string PATH_SEPARATOR = "\\";
        private UltraNavigationBar navigationBar = null;
        private UltraTree tree = null;

        public FileSystemSupport( UltraNavigationBar navigationBar, UltraTree tree )
        {
            //  Store references to the UltraNavigationBar and UltraTree
            this.navigationBar = navigationBar;
            this.tree = tree;

            //  Create the images we will use for the drives, folders, etc.
            this.CreateImages();

            //  Assign the folder image to the general node and location appearances.
            this.navigationBar.LocationSettings.Appearance.Image = this.GetImage( Images.Folder );
            this.tree.Override.NodeAppearance.Image = this.GetImage( Images.Folder );

            //  Synchronize the ImageSize properties for each control.
            this.tree.Override.ImageSize = this.navigationBar.ImageSizeResolved;

            //  Since we are lazily populating the nodes collections,
            //  show the expansion indicator initially for all nodes.
            this.tree.Override.ShowExpansionIndicator = ShowExpansionIndicator.CheckOnExpand;

            //  Set any additional properties on the UltraTree.
            this.tree.ScrollBounds = ScrollBounds.ScrollToFill;
            this.tree.Override.SelectionType = SelectType.Single;
            this.tree.HideSelection = false;

            //  Add an action button so the end user can refresh the directories.
            this.navigationBar.ActionButtons.Clear();
            UltraNavigationBarActionButton actionButton = this.navigationBar.ActionButtons.Add( "Refresh" );
            actionButton.Settings.Appearance.Image = this.GetImage( Images.Refresh );

            //  Restrict the width of the location's text button so very long
            //  directory names don't hog up all the space.
            this.navigationBar.LocationSettings.MaximumTextButtonWidth = 100;

            //  Restrict the number of items that can appear in the locations dropdown list.
            this.navigationBar.LocationSettings.MaximumDropDownItems = 10;

            //  Register as a listener for the events of interest
            this.HookEvents( true );
        }

        private void HookEvents( bool hook )
        {
            if ( hook )
            {
                //  NavigationBar
                this.navigationBar.InitializeLocations += new InitializeLocationsHandler(this.OnNavigationBarInitializeLocations);
                this.navigationBar.SelectedLocationChanged += new SelectedLocationChangedHandler(this.OnNavigationBarSelectedLocationChanged);
                this.navigationBar.ActionButtonClicked += new ActionButtonClickedHandler(this.OnNavigationBarActionButtonClicked);
                this.navigationBar.ActionButtonToolTipDisplaying += new ActionButtonToolTipDisplayingHandler(this.OnNavigationBarActionButtonToolTipDisplaying);

                //  Tree
                this.tree.BeforeExpand += new BeforeNodeChangedEventHandler(this.OnTreeBeforeExpand);
                this.tree.AfterActivate += new AfterNodeChangedEventHandler(this.OnTreeAfterActivate);
            }
            else
            {
                //  NavigationBar
                this.navigationBar.InitializeLocations -= new InitializeLocationsHandler(this.OnNavigationBarInitializeLocations);
                this.navigationBar.SelectedLocationChanged -= new SelectedLocationChangedHandler(this.OnNavigationBarSelectedLocationChanged);
                this.navigationBar.ActionButtonClicked -= new ActionButtonClickedHandler(this.OnNavigationBarActionButtonClicked);
                this.navigationBar.ActionButtonToolTipDisplaying += new ActionButtonToolTipDisplayingHandler(this.OnNavigationBarActionButtonToolTipDisplaying);

                //  Tree
                this.tree.BeforeExpand -= new BeforeNodeChangedEventHandler(this.OnTreeBeforeExpand);
                this.tree.AfterActivate -= new AfterNodeChangedEventHandler(this.OnTreeAfterActivate);
            }
        }

    }
Requirements

Target Platforms: Windows 10, Windows 8.1, Windows 8, Windows 7, Windows Server 2012, Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

See Also