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PropertyChanged Event

Summary

Occurs when a property value in this ImageViewer changes.

Syntax

Java

WinRT C#

public event PropertyChangedEventHandler PropertyChanged

Public Event PropertyChanged As PropertyChangedEventHandler

public event PropertyChangedEventHandler PropertyChanged

public void addPropertyChangedListener(PropertyChangeListener listener) 
public void removePropertyChangedListener(PropertyChangeListener listener)

add_PropertyChanged(function(sender, e)) 
remove_PropertyChanged(function(sender, e))

Event Data

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

Property	Description
PropertyName

Remarks

Most of the properties of this ImageViewer will fire the PropertyChanged event when the value changes. When this happens, the value of PropertyChangedEventArgs.PropertyName of the event data will be set to the name of the property that was changed. For example, the PropertyChangedEventArgs.PropertyName will be set to "ScaleFactor" when ScaleFactor changes and "ScrollOffset" when ScrollOffset changes.

System.ComponentModel.PropertyChangedEventArgs

Example

WinRT C#

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.Controls; 
 
public void PropertyChangedExample() 
{ 
   // Hook to the property changed event of the viewer 
   _viewer.PropertyChanged += _viewer_PropertyChanged; 
   _viewer.ScrollOffset = new Point(100, 100); 
} 
void _viewer_PropertyChanged(object sender, System.ComponentModel.PropertyChangedEventArgs e) 
{ 
   // Check the property name, we are interested in "ScaleFactor" and "ScrollOffset" 
   string  propertyName = e.PropertyName; 
   if (propertyName == "ScaleFactor" ||   propertyName == "ScrollOffset") 
   { 
      _infoLabel.Text = propertyName + "Changed"; 
   } 
}