DocumentPreviewControl.ShowingEditingFieldEditor Event

Occurs when the editor for the edit field is about to be shown. Allows you to prevent the editor from being displayed.

Assembly : DevExpress.Xpf.Printing.v25.2.dll

NuGet Package : DevExpress.Wpf.Printing

Declaration

C#
VB.NET

csharp

public event ShowingEditingFieldEditorEventHandler ShowingEditingFieldEditor

Public Event ShowingEditingFieldEditor As ShowingEditingFieldEditorEventHandler

Event Data

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

Property	Description
Cancel	Gets or sets a value that indicates whether the editor should be opened.
EditingField	Gets the edit field for which the event is raised. Inherited from EditingFieldEditorEventArgsBase.
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.
Source	Gets or sets a reference to the object that raised the event. Inherited from RoutedEventArgs.

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 following code prevents the editors for the Check Box and Picture Box fields from being displayed:

MainWindow.xaml

xaml

<Window x:Class="ValidateEditingFields_MVVM.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:ValidateEditingFields_MVVM"
        xmlns:dxp="http://schemas.devexpress.com/winfx/2008/xaml/printing"
        xmlns:dxmvvm="http://schemas.devexpress.com/winfx/2008/xaml/mvvm"
        Title="MainWindow" Height="450" Width="800">
    <Window.DataContext>
        <local:ViewModel />
    </Window.DataContext>
    <Grid>
        <dxp:DocumentPreviewControl RequestDocumentCreation="True"
                                    DocumentSource="{Binding Report}"
                                    HighlightEditingFields="True">
            <dxmvvm:Interaction.Behaviors>
                <dxmvvm:EventToCommand Event="{x:Static dxp:DocumentPreviewControl.ShowingEditingFieldEditorEvent}"
                                       PassEventArgsToCommand="True"
                                       Command="{Binding OnShowingEditingFieldEditorCommand}" />
            </dxmvvm:Interaction.Behaviors>
        </dxp:DocumentPreviewControl>
    </Grid>
</Window>

ViewModel.cs
ViewModel.vb

csharp

using DevExpress.Mvvm;
using DevExpress.Mvvm.DataAnnotations;
using DevExpress.Xpf.Printing;
using DevExpress.XtraReports.UI;
using System;

namespace ValidateEditingFields_MVVM {
    public class ViewModel : ViewModelBase {
        [Command]
        public void OnShowingEditingFieldEditor(ShowingEditingFieldEditorEventArgs args) {
            if(args.EditingField.ID == "CheckField" || args.EditingField.ID == "ImageField")
                args.Cancel = true;
        }
    }
}

Imports DevExpress.Mvvm
Imports DevExpress.Mvvm.DataAnnotations
Imports DevExpress.Xpf.Printing
Imports DevExpress.XtraReports.UI
Imports System

Namespace ValidateEditingFields_MVVM
    Public Class ViewModel
        Inherits ViewModelBase
        <Command>
        Public Sub OnShowingEditingFieldEditor(ByVal args As ShowingEditingFieldEditorEventArgs)
            If args.EditingField.ID = "CheckField" OrElse args.EditingField.ID = "ImageField" Then
                args.Cancel = True
            End If
        End Sub
    End Class
End Namespace

View Example: How to Validate the Editing Field Value in the Document Preview