TreeViewControl.GetIsEditorActivationAction Event

Allows you to specify an action (key down, text input, or left mouse button click) to activate the focused editor.

Namespace: DevExpress.Xpf.Grid

Assembly: DevExpress.Xpf.Grid.v26.1.dll

Declaration

C#

public event EventHandler<TreeViewGetIsEditorActivationActionEventArgs> GetIsEditorActivationAction

VB.NET

Public Event GetIsEditorActivationAction As EventHandler(Of TreeViewGetIsEditorActivationActionEventArgs)

Event Data

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

Property	Description
ActivationAction	Gets the type of user action that triggered the editor activation check.
Column	Gets the column that contains the active editor cell.
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.
IsActivationAction	Gets or sets if an in-place editor is activated for the focused cell.
KeyDownEventArgs	Gets key event data if the editor activation was triggered by a keystroke; otherwise, null.
MouseLeftButtonEventArgs	Gets mouse button event data if editor activation was triggered by a mouse click; otherwise, null.
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.
RowHandle	Gets the handle of the row that contains the active editor cell.
Source	Gets or sets a reference to the object that raised the event. Inherited from RoutedEventArgs.
TemplateChild	Gets an in-place editor specified in a cell template.
TextInputEventArgs	Gets text input event data if the activation was triggered by text input; otherwise, null.
Value	Gets the current value in the active editor.

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

Handle the GetIsEditorActivationAction event to disable or enable different in-place editor activation commands depending on specific conditions. Set the e.IsActivationAction property to false within an event handler to prevent a user from activating the editor.

Example: Prevent Editor Activation on Mouse Click

The following code snippet prevents users from activating an in-place editor by accidental mouse clicks:

XAML

<dx:ThemedWindow x:Class="TreeViewControlApp.MainWindow"
                 xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                 xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                 xmlns:dx="http://schemas.devexpress.com/winfx/2008/xaml/core"
                 xmlns:dxg="http://schemas.devexpress.com/winfx/2008/xaml/grid"
                 Title="TreeViewControl" Height="450" Width="600">
    <dxg:TreeViewControl x:Name="tree"
                         ChildNodesPath="Employees"
                         TreeViewFieldName="Name"
                         AllowEditing="True"
                         EditorShowMode="MouseUpFocused"
                         GetIsEditorActivationAction="OnGetIsEditorActivationAction"/>
</dx:ThemedWindow>

C#

private void OnGetIsEditorActivationAction(object sender, TreeViewGetIsEditorActivationActionEventArgs e)
{
    if (e.ActivationAction == ActivationAction.MouseLeftButtonDown || e.ActivationAction == ActivationAction.MouseLeftButtonUp) 
        e.IsActivationAction = false;
}

Related Events

TreeViewControl fires the following events to process user actions that activate an in-place editor:

ProcessEditorActivationAction

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

GetActiveEditorNeedsKey

Allows you to specify whether the active editor responds to certain keystrokes.