ScrollChanged Event

Visual Basic
C#
Objective-C
Java
C++

public event EventHandler<ImageViewerScrollChangedEventArgs> ScrollChanged

'Declaration
 
Public Event ScrollChanged As EventHandler(Of ImageViewerScrollChangedEventArgs)

'Usage
 
Dim instance As ImageViewer
Dim handler As EventHandler(Of ImageViewerScrollChangedEventArgs)
 
AddHandler instance.ScrollChanged, handler

public:
event EventHandler<ImageViewerScrollChangedEventArgs^>^ ScrollChanged

The event handler receives an argument of type ImageViewerScrollChangedEventArgs containing data related to this event. The following ImageViewerScrollChangedEventArgs properties provide information specific to this event.

Property	Description
Handled (Inherited from System.Windows.RoutedEventArgs)
HorizontalChange	Gets a value that indicates the change in horizontal offset for a ImageViewer or RasterImageViewer.
HorizontalOffset	Gets the updated horizontal offset value for a ImageViewer or RasterImageViewer.
OriginalSource (Inherited from System.Windows.RoutedEventArgs)
RoutedEvent (Inherited from System.Windows.RoutedEventArgs)
Source (Inherited from System.Windows.RoutedEventArgs)
VerticalChange	Gets a value that indicates the change in vertical offset for a ImageViewer or RasterImageViewer.
VerticalOffset	Gets the updated vertical offset value for a ImageViewer or RasterImageViewer.

This event is raised if any action through user interaction or programmatically that cause the scrollbars position, extent, view port size or visibility of the control.

Visual Basic
C#
WinRT C#
WinRT JavaScript
Silverlight C#
Silverlight VB

Copy Code

Imports Leadtools.Windows.Controls

Public Sub ImageViewer_ScrollChanged(ByVal viewer As ImageViewer)
    If Not viewer.Source Is Nothing Then
        ' Scroll to the image center
        AddHandler viewer.ScrollChanged, AddressOf viewer_ScrollChanged
        viewer.ScrollViewer.ScrollToHorizontalOffset(viewer.Source.Width / 2)
        viewer.ScrollViewer.ScrollToVerticalOffset(viewer.Source.Height / 2)
        RemoveHandler viewer.ScrollChanged, AddressOf viewer_ScrollChanged
    End If
End Sub

Private Sub viewer_ScrollChanged(ByVal sender As Object, ByVal e As ImageViewerScrollChangedEventArgs)
    Dim s As String = String.Format("HorizontalOffset : {0}, VerticalOffset : {1}", e.HorizontalOffset, e.VerticalOffset)
    MessageBox.Show(s)
End Sub

using Leadtools.Help;
using Leadtools.Windows.Controls;

public void ImageViewer_ScrollChanged(ImageViewer viewer)
{
   if (viewer.Source != null)
   {
      // Scroll to the image center
      viewer.ScrollChanged += new EventHandler<ImageViewerScrollChangedEventArgs>(viewer_ScrollChanged);
      viewer.ScrollViewer.ScrollToHorizontalOffset(viewer.Source.Width / 2);
      viewer.ScrollViewer.ScrollToVerticalOffset(viewer.Source.Height / 2);
      viewer.ScrollChanged -= new EventHandler<ImageViewerScrollChangedEventArgs>(viewer_ScrollChanged);
   }
}

void viewer_ScrollChanged(object sender, ImageViewerScrollChangedEventArgs e)
{
   string s = string.Format("HorizontalOffset : {0}, VerticalOffset : {1}", e.HorizontalOffset, e.VerticalOffset);
   MessageBox.Show(s);
}

using Leadtools.Help;
using Leadtools.Windows.Controls;

public void ImageViewer_ScrollChanged(ImageViewer viewer)
{
   if (viewer.Source != null)
   {
      // Scroll to the image center
      viewer.ScrollChanged += new EventHandler<ImageViewerScrollChangedEventArgs>(viewer_ScrollChanged);
      viewer.ScrollViewer.ScrollToHorizontalOffset(((BitmapSource)viewer.Source).PixelWidth/ 2);
      viewer.ScrollViewer.ScrollToVerticalOffset(((BitmapSource)viewer.Source).PixelHeight / 2);
      viewer.ScrollChanged -= new EventHandler<ImageViewerScrollChangedEventArgs>(viewer_ScrollChanged);
   }
}

void viewer_ScrollChanged(object sender, ImageViewerScrollChangedEventArgs e)
{
   string s = string.Format("HorizontalOffset : {0}, VerticalOffset : {1}", e.HorizontalOffset, e.VerticalOffset);
   MessageBox.Show(s);
}

Imports Leadtools
Imports Leadtools.Windows.Controls

Public Sub ImageViewer_ScrollChanged(ByVal viewer As ImageViewer)
   If Not viewer.Source Is Nothing Then
      ' Scroll to the image center
      AddHandler viewer.ScrollChanged, AddressOf viewer_ScrollChanged
      viewer.ScrollViewer.ScrollToHorizontalOffset((CType(viewer.Source, BitmapSource)).PixelWidth / 2)
      viewer.ScrollViewer.ScrollToVerticalOffset((CType(viewer.Source, BitmapSource)).PixelHeight / 2)
      RemoveHandler viewer.ScrollChanged, AddressOf viewer_ScrollChanged
   End If
End Sub

Private Sub viewer_ScrollChanged(ByVal sender As Object, ByVal e As ImageViewerScrollChangedEventArgs)
   Dim s As String = String.Format("HorizontalOffset : {0}, VerticalOffset : {1}", e.HorizontalOffset, e.VerticalOffset)
   MessageBox.Show(s)
End Sub

Target Platforms

Reference

ImageViewer Class
ImageViewer Members