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Leadtools.Windows.Controls Namespace > ImagePanViewer Class : OnSourceChanged Method |
protected virtual void OnSourceChanged( RoutedPropertyChangedEventArgs<ImageViewer> e )
'Declaration Protected Overridable Sub OnSourceChanged( _ ByVal e As RoutedPropertyChangedEventArgs(Of ImageViewer) _ )
'Usage Dim instance As ImagePanViewer Dim e As RoutedPropertyChangedEventArgs(Of ImageViewer) instance.OnSourceChanged(e)
protected: virtual void OnSourceChanged( RoutedPropertyChangedEventArgs<ImageViewer^>^ e )
Raising an event invokes the event handler through a delegate.
The OnSourceChanged method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.
Notes to Inheritors: When overriding OnSourceChanged in a derived class, be sure to call the base class's OnSourceChanged method so that registered delegates receive the event.
Imports Leadtools.Windows.Controls Public Sub ImagePanViewer_SourceChanged(ByVal panViewer As ImagePanViewer) ' set up the event handlers AddHandler panViewer.StrokeChanged, AddressOf panViewer_StrokeChanged AddHandler panViewer.SourceChanged, AddressOf panViewer_SourceChanged AddHandler panViewer.InnerBrushChanged, AddressOf panViewer_InnerBrushChanged AddHandler panViewer.OuterBrushChanged, AddressOf panViewer_OuterBrushChanged AddHandler panViewer.PositionChanged, AddressOf panViewer_PositionChanged Dim viewerOld As ImageViewer = panViewer.Source ' fires the SourceChanged event twice panViewer.Source = Nothing panViewer.Source = viewerOld ' change some properties panViewer.Stroke = Brushes.Black panViewer.StrokeThickness = 2 panViewer.Position = New Point(20, 20) End Sub Private Sub panViewer_PositionChanged(ByVal sender As Object, ByVal e As RoutedPropertyChangedEventArgs(Of Point)) Dim panViewer As ImagePanViewer = CType(sender, ImagePanViewer) If Not panViewer Is Nothing Then Console.WriteLine("Position Changed to " & panViewer.Position.ToString()) End If End Sub Private Sub panViewer_OuterBrushChanged(ByVal sender As Object, ByVal e As RoutedPropertyChangedEventArgs(Of Brush)) Dim panViewer As ImagePanViewer = CType(sender, ImagePanViewer) If Not panViewer Is Nothing Then Console.WriteLine("Inner Brush Changed to " & panViewer.OuterBrush.ToString() & "Color") End If End Sub Private Sub panViewer_InnerBrushChanged(ByVal sender As Object, ByVal e As RoutedPropertyChangedEventArgs(Of Brush)) Dim panViewer As ImagePanViewer = CType(sender, ImagePanViewer) If Not panViewer Is Nothing Then Console.WriteLine("Inner Brush Changed to " & panViewer.InnerBrush.ToString() & "Color") End If End Sub Private Sub panViewer_StrokeChanged(ByVal sender As Object, ByVal e As RoutedPropertyChangedEventArgs(Of Brush)) Dim panViewer As ImagePanViewer = CType(sender, ImagePanViewer) If Not panViewer Is Nothing Then Console.WriteLine("Rectangle Stroke Changed to " & panViewer.StrokeThickness.ToString() & "Thickness and to" & panViewer.Stroke.ToString() & "Color") End If End Sub Private Sub panViewer_SourceChanged(ByVal sender As Object, ByVal e As RoutedPropertyChangedEventArgs(Of ImageViewer)) Dim panViewer As ImagePanViewer = CType(sender, ImagePanViewer) If Not panViewer Is Nothing Then If panViewer.Source Is Nothing Then Console.WriteLine("There is no Viewer control associated with the ImagePanViewer Control") Else Console.WriteLine("A Viewer is now associated with the ImagePanViewer Control") End If End If End Sub
using Leadtools.Help; using Leadtools.Windows.Controls; public void ImagePanViewer_SourceChanged(ImagePanViewer panViewer) { // set up the event handlers panViewer.StrokeChanged += new RoutedPropertyChangedEventHandler<Brush>(panViewer_StrokeChanged); panViewer.SourceChanged += new RoutedPropertyChangedEventHandler<ImageViewer>(panViewer_SourceChanged); panViewer.InnerBrushChanged +=new RoutedPropertyChangedEventHandler<Brush>(panViewer_InnerBrushChanged); panViewer.OuterBrushChanged +=new RoutedPropertyChangedEventHandler<Brush>(panViewer_OuterBrushChanged); panViewer.PositionChanged += new RoutedPropertyChangedEventHandler<Point>(panViewer_PositionChanged); ImageViewer viewerOld = panViewer.Source; // fires the SourceChanged event twice panViewer.Source = null; panViewer.Source = viewerOld; // change some properties panViewer.Stroke = Brushes.Black; panViewer.StrokeThickness = 2; panViewer.Position = new Point(20, 20); } void panViewer_PositionChanged(object sender, RoutedPropertyChangedEventArgs<Point> e) { ImagePanViewer panViewer = (ImagePanViewer)sender; if (panViewer != null) Console.WriteLine("Position Changed to " + panViewer.Position.ToString()); } void panViewer_OuterBrushChanged(object sender, RoutedPropertyChangedEventArgs<Brush> e) { ImagePanViewer panViewer = (ImagePanViewer)sender; if (panViewer != null) Console.WriteLine("Inner Brush Changed to " + panViewer.OuterBrush.ToString() + "Color"); } void panViewer_InnerBrushChanged(object sender, RoutedPropertyChangedEventArgs<Brush> e) { ImagePanViewer panViewer = (ImagePanViewer)sender; if (panViewer != null) Console.WriteLine("Inner Brush Changed to " + panViewer.InnerBrush.ToString() + "Color"); } private void panViewer_StrokeChanged(object sender, RoutedPropertyChangedEventArgs<Brush> e) { ImagePanViewer panViewer = (ImagePanViewer)sender; if(panViewer != null) Console.WriteLine("Rectangle Stroke Changed to " + panViewer.StrokeThickness.ToString() +"Thickness and to" + panViewer.Stroke.ToString()+ "Color"); } private void panViewer_SourceChanged(object sender, RoutedPropertyChangedEventArgs<ImageViewer> e) { ImagePanViewer panViewer = (ImagePanViewer)sender; if(panViewer != null) { if(panViewer.Source == null) Console.WriteLine("There is no Viewer control associated with the ImagePanViewer Control"); else Console.WriteLine("A Viewer is now associated with the ImagePanViewer Control"); } }
using Leadtools.Help; using Leadtools.Windows.Controls; public void ImagePanViewer_SourceChanged(ImagePanViewer panViewer) { // set up the event handlers panViewer.StrokeChanged += new RoutedPropertyChangedEventHandler<Brush>(panViewer_StrokeChanged); panViewer.SourceChanged += new RoutedPropertyChangedEventHandler<ImageViewer>(panViewer_SourceChanged); panViewer.InnerBrushChanged += new RoutedPropertyChangedEventHandler<Brush>(panViewer_InnerBrushChanged); panViewer.OuterBrushChanged += new RoutedPropertyChangedEventHandler<Brush>(panViewer_OuterBrushChanged); panViewer.PositionChanged += new RoutedPropertyChangedEventHandler<Point>(panViewer_PositionChanged); ImageViewer viewerOld = panViewer.Source; // fires the SourceChanged event twice panViewer.Source = null; panViewer.Source = viewerOld; // change some properties panViewer.Stroke = new SolidColorBrush(Colors.Black); panViewer.StrokeThickness = 2; panViewer.Position = new Point(20, 20); } void panViewer_PositionChanged(object sender, RoutedPropertyChangedEventArgs<Point> e) { ImagePanViewer panViewer = (ImagePanViewer)sender; if (panViewer != null) Console.WriteLine("Position Changed to " + panViewer.Position.ToString()); } void panViewer_OuterBrushChanged(object sender, RoutedPropertyChangedEventArgs<Brush> e) { ImagePanViewer panViewer = (ImagePanViewer)sender; if (panViewer != null) Console.WriteLine("Inner Brush Changed to " + panViewer.OuterBrush.ToString() + "Color"); } void panViewer_InnerBrushChanged(object sender, RoutedPropertyChangedEventArgs<Brush> e) { ImagePanViewer panViewer = (ImagePanViewer)sender; if (panViewer != null) Console.WriteLine("Inner Brush Changed to " + panViewer.InnerBrush.ToString() + "Color"); } private void panViewer_StrokeChanged(object sender, RoutedPropertyChangedEventArgs<Brush> e) { ImagePanViewer panViewer = (ImagePanViewer)sender; if (panViewer != null) Console.WriteLine("Rectangle Stroke Changed to " + panViewer.StrokeThickness.ToString() + "Thickness and to" + panViewer.Stroke.ToString() + "Color"); } private void panViewer_SourceChanged(object sender, RoutedPropertyChangedEventArgs<ImageViewer> e) { ImagePanViewer panViewer = (ImagePanViewer)sender; if (panViewer != null) { if (panViewer.Source == null) Console.WriteLine("There is no Viewer control associated with the ImagePanViewer Control"); else Console.WriteLine("A Viewer is now associated with the ImagePanViewer Control"); } }
Imports Leadtools.Windows.Controls Public Sub ImagePanViewer_SourceChanged(ByVal panViewer As ImagePanViewer) ' set up the event handlers AddHandler panViewer.StrokeChanged, AddressOf panViewer_StrokeChanged AddHandler panViewer.SourceChanged, AddressOf panViewer_SourceChanged AddHandler panViewer.InnerBrushChanged, AddressOf panViewer_InnerBrushChanged AddHandler panViewer.OuterBrushChanged, AddressOf panViewer_OuterBrushChanged AddHandler panViewer.PositionChanged, AddressOf panViewer_PositionChanged Dim viewerOld As ImageViewer = panViewer.Source ' fires the SourceChanged event twice panViewer.Source = Nothing panViewer.Source = viewerOld ' change some properties panViewer.Stroke = New SolidColorBrush(Colors.Black) panViewer.StrokeThickness = 2 panViewer.Position = New Point(20, 20) End Sub Private Sub panViewer_PositionChanged(ByVal sender As Object, ByVal e As RoutedPropertyChangedEventArgs(Of Point)) Dim panViewer As ImagePanViewer = CType(sender, ImagePanViewer) If Not panViewer Is Nothing Then Console.WriteLine("Position Changed to " & panViewer.Position.ToString()) End If End Sub Private Sub panViewer_OuterBrushChanged(ByVal sender As Object, ByVal e As RoutedPropertyChangedEventArgs(Of Brush)) Dim panViewer As ImagePanViewer = CType(sender, ImagePanViewer) If Not panViewer Is Nothing Then Console.WriteLine("Inner Brush Changed to " & panViewer.OuterBrush.ToString() & "Color") End If End Sub Private Sub panViewer_InnerBrushChanged(ByVal sender As Object, ByVal e As RoutedPropertyChangedEventArgs(Of Brush)) Dim panViewer As ImagePanViewer = CType(sender, ImagePanViewer) If Not panViewer Is Nothing Then Console.WriteLine("Inner Brush Changed to " & panViewer.InnerBrush.ToString() & "Color") End If End Sub Private Sub panViewer_StrokeChanged(ByVal sender As Object, ByVal e As RoutedPropertyChangedEventArgs(Of Brush)) Dim panViewer As ImagePanViewer = CType(sender, ImagePanViewer) If Not panViewer Is Nothing Then Console.WriteLine("Rectangle Stroke Changed to " & panViewer.StrokeThickness.ToString() & "Thickness and to" & panViewer.Stroke.ToString() & "Color") End If End Sub Private Sub panViewer_SourceChanged(ByVal sender As Object, ByVal e As RoutedPropertyChangedEventArgs(Of ImageViewer)) Dim panViewer As ImagePanViewer = CType(sender, ImagePanViewer) If Not panViewer Is Nothing Then If panViewer.Source Is Nothing Then Console.WriteLine("There is no Viewer control associated with the ImagePanViewer Control") Else Console.WriteLine("A Viewer is now associated with the ImagePanViewer Control") End If End If End Sub