GridViewBase.ShowingEditor Event

Allows you to prevent an end user from activating editors of individual cells.

Namespace: DevExpress.Xpf.Grid

Assembly: DevExpress.Xpf.Grid.v24.2.dll

NuGet Package: DevExpress.Wpf.Grid.Core

Declaration

C#

public event ShowingEditorEventHandler ShowingEditor

VB.NET

Public Event ShowingEditor As ShowingEditorEventHandler

Event Data

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

Property	Description
Cancel	Gets or sets the value indicating whether to prevent showing the editor. Inherited from ShowingEditorEventArgsBase.
Column	Gets a column, for which an event has been raised.
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.
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.
Row	Gets the data row for which an event has been raised.
RowHandle	Gets or sets the row handle, for which an event has been raised. Inherited from EditorEventArgsBase.
Source	Gets or sets a reference to the object that raised the event. Inherited from RoutedEventArgs.
Value	Gets the edit value stored in the editor, for which an event has been raised. Inherited from EditorEventArgsBase.

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

The ShowingEditor event is raised before the focused cell’s editor is activated allowing you to cancel the action and prevent its value from being edited. To do this, set the event parameter’s Cancel property to false.

The following example shows how to disable GridControl rows based on their values.

View Example: Disable Rows Based on Their Values

DisableRowBehavior.cs

void OnEditorShowing(object sender, ShowingEditorEventArgs e) {
    if(e.Column.FieldName != nameof(Item.AllowEdit))
        e.Cancel = !(AssociatedObject.DataControl.CurrentItem as Item).AllowEdit;
}

DisableRowBehavior.vb

Private Sub OnEditorShowing(ByVal sender As Object, ByVal e As ShowingEditorEventArgs)
    If e.Column.FieldName <> NameOf(Item.AllowEdit) Then e.Cancel = Not (TryCast(AssociatedObject.DataControl.CurrentItem, Item)).AllowEdit
End Sub

Tip

You can conditionally disable data cells or make cells read-only via the BaseColumn.IsEnabledBinding and BaseColumn.IsReadOnlyBinding properties.

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#

wpf-data-grid-disable-rows-based-on-their-values/CS/WpfApplication/DisableRowBehavior.cs#L8

    base.OnAttached();
    AssociatedObject.ShowingEditor += OnEditorShowing;
}

VB.NET

wpf-data-grid-disable-rows-based-on-their-values/VB/WpfApplication/DisableRowBehavior.vb#L11

    MyBase.OnAttached()
    AddHandler AssociatedObject.ShowingEditor, AddressOf OnEditorShowing
End Sub