TreeList.ShowingEditor Event

Fires before the TreeList is switched to edit mode.

Namespace: DevExpress.XtraTreeList

Assembly: DevExpress.XtraTreeList.v18.2.dll

Declaration

C#

[DXCategory("Editor")]
public event CancelEventHandler ShowingEditor

VB.NET

<DXCategory("Editor")>
Public Event ShowingEditor As CancelEventHandler

Event Data

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

Property	Description
Cancel	Gets or sets a value indicating whether the event should be canceled.

Remarks

Write a ShowingEditor event handler to perform specific actions each time a cell editor is about to be displayed. It can be used to prohibit switching the TreeList control to edit mode. Set the Cancel parameter to true for this purpose.

Cells in the Tree List control are identified by a corresponding column and node. For the cell currently being processed, the column and node are identified by the TreeList.FocusedColumn and TreeList.FocusedNode properties respectively.

You can prohibit cell editing by disabling the TreeListOptionsBehavior.Editable option. Cells of a particular column can also be made read-only. Enable the desired column’s TreeListColumn.ReadOnly option for this purpose. This option is available via the column’s TreeListColumn.OptionsColumn property. Write a ShowingEditor event handler to prohibit cell editing within specific rows or make individual cells read-only.

Note

The ShowingEditor event does not fire for cells within the Auto Filter Row .

Related GitHub Examples

The following code snippet (auto-collected from DevExpress Examples) contains a reference to the ShowingEditor event.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

C#

XAF_treelisteditor-how-to-enable-in-place-editing-in-the-winforms-tree-list-view-xpo-e443/CS/WinSolution.Module.Win/TreeListAppearanceControllerEx.cs#L12

if (base.Active.ResultValue && base.View != null && base.View.Editor != null && base.View.Editor is TreeListEditor && ((TreeListEditor)base.View.Editor).TreeList != null) {
    ((TreeListEditor)base.View.Editor).TreeList.ShowingEditor += new System.ComponentModel.CancelEventHandler(control_ShowingEditor);
}

VB.NET

XAF_treelisteditor-how-to-enable-in-place-editing-in-the-winforms-tree-list-view-xpo-e443/VB/WinSolution.Module.Win/TreeListAppearanceControllerEx.vb#L14

If MyBase.Active.ResultValue AndAlso MyBase.View IsNot Nothing AndAlso MyBase.View.Editor IsNot Nothing AndAlso TypeOf MyBase.View.Editor Is TreeListEditor AndAlso CType(MyBase.View.Editor, TreeListEditor).TreeList IsNot Nothing Then
    AddHandler CType(View.Editor, TreeListEditor).TreeList.ShowingEditor, AddressOf control_ShowingEditor
End If