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NavigationPaneCollapsing イベント

ナビゲーション ペインが縮小される前に発生します。
シンタックス
'宣言
 
Public Event NavigationPaneCollapsing As NavigationPaneCollapsingEventHandler
public event NavigationPaneCollapsingEventHandler NavigationPaneCollapsing
イベント データ

イベント ハンドラが、このイベントに関連するデータを含む、NavigationPaneCollapsingEventArgs 型の引数を受け取りました。次の NavigationPaneCollapsingEventArgs プロパティには、このイベントの固有の情報が記載されます。

プロパティ解説
Cancel System.ComponentModel.CancelEventArgsから継承されます。 
PreferredWidth Infragistics.Win.UltraWinExplorerBar.NavigationPaneExpandedStateChangingEventArgsBaseから継承されます。ナビゲーション ペンが縮小または展開された時の UltraExplorerBar コントロールの幅を取得または設定します。
解説

注： ExplorerBar の System.Windows.Forms.Control.Dock プロパティが 'None' 以外の値に設定されると、縮小可能なナビゲーション ペインの機能は適切に機能しません。これは、この機能がコントロールの System.Windows.Forms.Control.Width プロパティを設定することに依存しているためですが、これは Dock プロパティのすべての値でサポートされるとは限りません。ただし、この制限はパブリックのオブジェクト モデルを使用して解決できます。末端の開発者は、 NavigationPaneExpanding イベントと NavigationPaneCollapsing イベントを処理して、ExplorerBar の System.Windows.Forms.Control.Parent の幅を、イベント引数の NavigationPaneExpandedStateChangingEventArgsBase.PreferredWidth プロパティの値と同じ値に設定できます。

末端の開発者は、NavigationPaneCollapsing イベントをキャンセルする（イベント引数の Cancel プロパティを True に設定する）ことによって、ナビゲーション ペインが縮小されないようにすることができます。

使用例
Imports Infragistics.Win
Imports Infragistics.Win.UltraWinExplorerBar

    '   Handles the Form's 'Load' event
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        '   Add the ExplorerBar to the Panel's Controls collection
        Me.panel1.Controls.AddRange(New System.Windows.Forms.Control() {Me.ultraExplorerBar1})

        '   Dock the Panel control to the left side of the form
        Me.panel1.Dock = System.Windows.Forms.DockStyle.Left

        '   Dock the ExplorerBar to completely fill the Panel control
        Me.ultraExplorerBar1.Dock = System.Windows.Forms.DockStyle.Fill

        '   Set the NavigationPaneExpansionMode property to 'OnButtonClickOrSizeChanged'
        '   so that the navigation pane's expanded state is changed on both button clicks
        '   and control resizing.
        Me.ultraExplorerBar1.NavigationPaneExpansionMode = NavigationPaneExpansionMode.OnButtonClickOrSizeChanged

        '   Set the NavigationPaneExpansionThreshold property so that resizing the
        '   width smaller than 50 pixels causes the navigation pane to collapse.
        Me.ultraExplorerBar1.NavigationPaneExpansionThreshold = 50

        '	Hook the NavigationPaneExpanding and NavigationPaneCollapsing events
        AddHandler Me.ultraExplorerBar1.NavigationPaneExpanding, AddressOf Me.ultraExplorerBar1_NavigationPaneExpanding
        AddHandler Me.ultraExplorerBar1.NavigationPaneCollapsing, AddressOf Me.ultraExplorerBar1_NavigationPaneCollapsing

        '	Set the NavigationPaneExpandedState to 'Collapsed' so that the ExplorerBar is initially collapsed
        Me.ultraExplorerBar1.NavigationPaneExpandedState = NavigationPaneExpandedState.Collapsed
    End Sub

    '	Handles the ExplorerBar's 'NavigationPaneCollapsing' event.
    Private Sub ultraExplorerBar1_NavigationPaneCollapsing(ByVal sender As Object, ByVal e As NavigationPaneCollapsingEventArgs)
        Dim explorerBar As UltraExplorerBar = sender
        Me.OnNavigationPaneExpandedStateChanging(explorerBar, e)
    End Sub

    '	Handles the ExplorerBar's 'NavigationPaneExpanding' event.
    Private Sub ultraExplorerBar1_NavigationPaneExpanding(ByVal sender As Object, ByVal e As NavigationPaneExpandingEventArgs)
        Dim explorerBar As UltraExplorerBar = sender
        Me.OnNavigationPaneExpandedStateChanging(explorerBar, e)
    End Sub

    '	Helper method which handles synchronization of the width of
    '	the ExplorerBar's parent with that of the ExplorerBar.
    Private Sub OnNavigationPaneExpandedStateChanging(ByVal explorerBar As UltraExplorerBar, ByVal e As NavigationPaneExpandedStateChangingEventArgsBase)

        '	If the ExplorerBar's Dock property is set to 'Fill',
        '	synchronize the width of the container with that of
        '	the ExplorerBar.
        If explorerBar.Dock = DockStyle.Fill Then

            Dim parentControl As Control = explorerBar.Parent
            If Not parentControl Is Nothing Then parentControl.Width = e.PreferredWidth
        End If

    End Sub
using Infragistics.Win;
using Infragistics.Win.UltraWinExplorerBar;
using System.Diagnostics;

		//	Handles the Form's 'Load' event.
		private void Form1_Load(object sender, System.EventArgs e)
		{
			//	Add the ExplorerBar to the Panel's Controls collection
			this.panel1.Controls.AddRange(new System.Windows.Forms.Control[] { this.ultraExplorerBar1 } );

			//	Dock the Panel control to the left side of the form
			this.panel1.Dock = System.Windows.Forms.DockStyle.Left;

			//   Set the NavigationPaneExpansionMode property to 'OnButtonClickOrSizeChanged'
			//   so that the navigation pane's expanded state is changed on both button clicks
			//   and control resizing.
			this.ultraExplorerBar1.NavigationPaneExpansionMode = NavigationPaneExpansionMode.OnButtonClickOrSizeChanged;

			//   Set the NavigationPaneExpansionThreshold property so that resizing the
			//   width smaller than 50 pixels causes the navigation pane to collapse.
			this.ultraExplorerBar1.NavigationPaneExpansionThreshold = 50;

			//	Hook the NavigationPaneExpanding and NavigationPaneCollapsing events
			this.ultraExplorerBar1.NavigationPaneExpanding += new Infragistics.Win.UltraWinExplorerBar.NavigationPaneExpandingEventHandler(this.ultraExplorerBar1_NavigationPaneExpanding);
			this.ultraExplorerBar1.NavigationPaneCollapsing += new Infragistics.Win.UltraWinExplorerBar.NavigationPaneCollapsingEventHandler(this.ultraExplorerBar1_NavigationPaneCollapsing);		

			//	Set the NavigationPaneExpandedState to 'Collapsed' so that the ExplorerBar is initially collapsed
			this.ultraExplorerBar1.NavigationPaneExpandedState = NavigationPaneExpandedState.Collapsed;
		}

		//	Handles the ExplorerBar's 'NavigationPaneCollapsing' event.
		private void ultraExplorerBar1_NavigationPaneCollapsing(object sender, Infragistics.Win.UltraWinExplorerBar.NavigationPaneCollapsingEventArgs e)
		{
			UltraExplorerBar explorerBar = sender as UltraExplorerBar;
			this.OnNavigationPaneExpandedStateChanging( explorerBar, e );
		}

		//	Handles the ExplorerBar's 'NavigationPaneExpanding' event.
		private void ultraExplorerBar1_NavigationPaneExpanding(object sender, Infragistics.Win.UltraWinExplorerBar.NavigationPaneExpandingEventArgs e)
		{
			UltraExplorerBar explorerBar = sender as UltraExplorerBar;
			this.OnNavigationPaneExpandedStateChanging( explorerBar, e );		
		}

		//	Helper method which handles synchronization of the width of
		//	the ExplorerBar's parent with that of the ExplorerBar.
		private void OnNavigationPaneExpandedStateChanging( UltraExplorerBar explorerBar, NavigationPaneExpandedStateChangingEventArgsBase e )
		{
			//	If the ExplorerBar's Dock property is set to 'Fill',
			//	synchronize the width of the container with that of
			//	the ExplorerBar.
			if ( explorerBar.Dock == DockStyle.Fill )
			{
				Control parentControl = explorerBar.Parent;
				if ( parentControl != null )
					parentControl.Width = e.PreferredWidth;
			}
		}
参照