ArcGIS Engine Developer Guide

JAVA APPLICATION PROGRAMMING INTERFACE
The following code uses an anonymous inner class with the
IARControlEventsAdapter to add event listeners for onDocumentLoaded and
onDocumentUnloaded events to the arControl object:
arControl = new ARControl();
...
/*wire up the events for arControl*/
arControl.addIARControlEventsListener(new IARControlEventsAdapter(){
public void onDocumentLoaded(IARControlEventsOnDocumentLoadedEvent evt)
throws IOException{
/*set the statusbar text to point to the currently loaded document*/
java.awt.EventQueue.invokeLater(
new Runnable() {
public void run() {
statusLabel.setText(
" Document filename: "+ arControl.getDocumentFilename());
}
}
);
}
public void onDocumentUnloaded(
IARControlEventsOnDocumentUnloadedEvent evt) throws IOException{
/*set the statusbar text to empty string*/
java.awt.EventQueue.invokeLater(
new Runnable() {
public void run() {
statusLabel.setText("");
}
}
);
}
});
It is worthwhile to note that the events fired by the beans are custom events for
which the listeners are provided as part of the ArcGIS API for Java. Adding
listeners from the java.awt.event package, such as MouseListener, to the beans will
not be helpful as the JavaBeans do not fire those events. Instead, you could use
similar events, such as onMouseDown, onMouseUp, and onMouseMove, provided by
the corresponding event listener, which in the case of ARControl is
IARControlEvents.
In addition, these custom events are not fired from within Java’s event dispatch
thread. Whenever you wish to change the state of a pure Java GUI component
from within one of these events, be sure to do so via java.awt.EventQueue’s
invokeLater method. On the other hand, the ArcGIS components do not run in
Java’s event dispatch thread. Because of this, you can change their state directly
from within any of the custom ArcGIS events. For example, you could call
Map.refresh from within an ITransformEventsListener without using invokeLater.
196 • ArcGIS Engine Developer Guide