DataViewBase.ProcessEditorActivationAction Event

Allows you to specify whether the focused editor should process an activation action.

Namespace: DevExpress.Xpf.Grid

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

NuGet Package: DevExpress.Wpf.Grid.Core

Declaration

C#

public event EventHandler<ProcessEditorActivationActionEventArgs> ProcessEditorActivationAction

VB.NET

Public Event ProcessEditorActivationAction As EventHandler(Of ProcessEditorActivationActionEventArgs)

Event Data

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

Property	Description
ActivationAction	Gets an activation action’s type. Inherited from ActivationActionEventArgsBase.
Column	Gets or sets a grid column, for which an event has been raised. Inherited from EditorEventArgsBase.
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.
KeyDownEventArgs	Event arguments for the KeyDown activation action. Inherited from ActivationActionEventArgsBase.
MouseLeftButtonEventArgs	Event arguments for the MouseLeftButton activation action. Inherited from ActivationActionEventArgsBase.
OriginalSource	Gets the original reporting source as determined by pure hit testing, before any possible Source adjustment by a parent class. Inherited from RoutedEventArgs.
RaiseEventAgain	Gets or sets whether the event is raised again to make the focused editor process an activation action.
RoutedEvent	Gets or sets the RoutedEvent associated with this RoutedEventArgs instance. Inherited from RoutedEventArgs.
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.
TemplateChild	An in-place editor specified in a cell template. Inherited from ActivationActionEventArgsBase.
TextInputEventArgs	Event arguments for the TextInput activation action. Inherited from ActivationActionEventArgsBase.
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

A user can activate the focused cell’s in-place editor in the following ways:

• Click the required cell
• Press Enter
• Press F2
• Start typing.

When a user activates a cell editor, the default behavior passes the activation action to the editor. In some cases (for example, if you use a combination of CellDisplayTemplate and CellEditTemplate properties), the GridControl does not pass the action. You can use the ProcessEditorActivationAction event to change this behavior.

To Make the Focused Editor Process an Activation Action

1. Handle the ProcessEditorActivationAction event.
2. Use the ActivationAction and MouseLeftButtonEventArgs / KeyDownEventArgs / TextInputEventArgs properties to get the action’s information.
3. Set the RaiseEventAgain property to true to make the focused editor process the activation action.

Example 1

The following code sample demonstrates how to implement navigation in custom cell editors:

View Example: How to Specify Navigation in Custom Cell Editors

Xaml

<dxg:GridControl Name="grid" ItemsSource="{Binding Items}">
    <dxg:GridColumn FieldName="Country"/>
    <dxg:GridColumn FieldName="City">
        <dxg:GridColumn.CellTemplate>
            <DataTemplate>
                <dxe:ListBoxEdit x:Name="PART_Editor" ItemsSource="{Binding RowData.Row.Cities}"/>
            </DataTemplate>
        </dxg:GridColumn.CellTemplate>
    </dxg:GridColumn>
    <dxg:GridControl.View>
        <dxg:TableView ProcessEditorActivationAction="TableView_ProcessEditorActivationAction" />
    </dxg:GridControl.View>
</dxg:GridControl>

C#

void TableView_ProcessEditorActivationAction(object sender, DevExpress.Xpf.Grid.ProcessEditorActivationActionEventArgs e) {
    if (e.Column.FieldName == "City" 
     && (e.ActivationAction == ActivationAction.MouseLeftButtonDown 
      && e.MouseLeftButtonEventArgs.LeftButton == System.Windows.Input.MouseButtonState.Pressed))
        e.RaiseEventAgain = true;
}

VB.NET

Private Sub TableView_ProcessEditorActivationAction(ByVal sender As Object, ByVal e As DevExpress.Xpf.Grid.ProcessEditorActivationActionEventArgs)
    If e.Column.FieldName = "City" 
     AndAlso (e.ActivationAction = ActivationAction.MouseLeftButtonDown 
      AndAlso e.MouseLeftButtonEventArgs.LeftButton = System.Windows.Input.MouseButtonState.Pressed) 
    Then e.RaiseEventAgain = True
End Sub

Example 2

The following code sample shows how to make the Slider (which is specified as a custom editor) process the + and - keys after activating an editor:

C#

void TableView_ProcessEditorActivationAction(object sender, ProcessEditorActivationActionEventArgs e) {
    if(e.Column.FieldName == "HoursActive" && e.ActivationAction == ActivationAction.KeyDown) {
        e.RaiseEventAgain = IsSliderCommand(e.KeyDownEventArgs.Key);
    }
    if(e.Column.FieldName == "HoursActive" && e.ActivationAction == ActivationAction.MouseLeftButtonDown) {
        e.RaiseEventAgain = true;
    }
}

bool IsSliderCommand(Key key) {
    switch(key) {
        case Key.Add:
        case Key.Subtract:
        case Key.OemPlus:
        case Key.OemMinus:
            return true;
        default:
            return false;
    }
}

VB.NET

Private Sub TableView_ProcessEditorActivationAction(ByVal sender As Object, ByVal e As ProcessEditorActivationActionEventArgs)
    If e.Column.FieldName = "HoursActive" AndAlso e.ActivationAction = ActivationAction.KeyDown Then
        e.RaiseEventAgain = IsSliderCommand(e.KeyDownEventArgs.Key)
    End If
    If e.Column.FieldName = "HoursActive" AndAlso e.ActivationAction = ActivationAction.MouseLeftButtonDown Then
        e.RaiseEventAgain = True
    End If
End Sub

Private Function IsSliderCommand(ByVal key As Key) As Boolean
    Select Case key
        Case System.Windows.Input.Key.Add, System.Windows.Input.Key.Subtract, System.Windows.Input.Key.OemPlus, System.Windows.Input.Key.OemMinus
            Return True
        Case Else
            Return False
    End Select
End Function

Run Demo: Cell Editors

Process End User Actions

The GridControl provides the following events to process end user actions:

Event	Description
DataViewBase.GetIsEditorActivationAction	Allows you to specify whether an action (key down, text input, or mouse left button click) activates the focused editor.
DataViewBase.ProcessEditorActivationAction	Allows you to make the focused editor process an activation action.
DataViewBase.GetActiveEditorNeedsKey	Allows you to specify whether an active editor responds to keys that a user presses.

Related GitHub Examples

The following code snippets (auto-collected from DevExpress Examples) contain references to the ProcessEditorActivationAction 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.

XAML

wpf-data-grid-embed-a-richtextbox-into-grid-cells/CS/Window1.xaml#L52

<dxg:GridControl.View>
    <dxg:TableView Name="view" GetActiveEditorNeedsKey="view_GetActiveEditorNeedsKey" ProcessEditorActivationAction="view_ProcessEditorActivationAction"/>
</dxg:GridControl.View>

C#

how-to-specify-navigation-in-custom-cell-editors/CS/NavigationBehavior.cs#L9

base.OnAttached();
AssociatedObject.ProcessEditorActivationAction += TableView_ProcessEditorActivationAction;
AssociatedObject.GetActiveEditorNeedsKey += TableView_GetActiveEditorNeedsKey;

VB.NET

how-to-specify-navigation-in-custom-cell-editors/VB/NavigationBehavior.vb#L12

MyBase.OnAttached()
AddHandler AssociatedObject.ProcessEditorActivationAction, AddressOf TableView_ProcessEditorActivationAction
AddHandler AssociatedObject.GetActiveEditorNeedsKey, AddressOf TableView_GetActiveEditorNeedsKey