[news.eclipse.platform] ObservabelList question and databinding

[joelgreg@xxxxxxxxx (Joel Gregoire)]

Hi there,

I've been playing with Observables for a while and I'm wondering if I'm 
missing something. Is it possible to detect a change in one of the items 
within an ObservableList?? I can surely detect additions and removals but 
I can't detect a change of an item.

In the following snippet, 2 lists are bound together, I make a change to 
one and the second gets updated. Good. However the list change event is 
not fired. Do I need to register a listener for every item in the list? It 
has to be simple.

Any help is appreciated.

Thanks, JG

import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;

import org.eclipse.core.databinding.DataBindingContext;
import org.eclipse.core.databinding.observable.AbstractObservable;
import org.eclipse.core.databinding.observable.ChangeEvent;
import org.eclipse.core.databinding.observable.IChangeListener;
import org.eclipse.core.databinding.observable.Realm;
import org.eclipse.core.databinding.observable.list.IListChangeListener;
import org.eclipse.core.databinding.observable.list.IObservableList;
import org.eclipse.core.databinding.observable.list.ListChangeEvent;
import org.eclipse.core.databinding.observable.list.WritableList;
import org.eclipse.jface.databinding.swt.SWTObservables;
import org.eclipse.swt.SWT;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;

public class Test 
{
	public static void main(String[] args) 
	{
		final Display display = new Display();
		Realm.runWithDefault(SWTObservables.getRealm(display), new Runnable() 
		{
			public void run() 
			{
				Shell shell = new View().createShell();
			}
		});
	}

	public static abstract class AbstractModelObject extends 
AbstractObservable
	{
		public AbstractModelObject()
		{
			super( Realm.getDefault() );
		}

		private PropertyChangeSupport propertyChangeSupport = new 
PropertyChangeSupport(this);

		public void addPropertyChangeListener(PropertyChangeListener listener)
		{
			propertyChangeSupport.addPropertyChangeListener(listener);
		}

		public void addPropertyChangeListener(String propertyName, 
PropertyChangeListener listener) 
		{
			propertyChangeSupport.addPropertyChangeListener(propertyName, listener);
		}

		public void removePropertyChangeListener(PropertyChangeListener listener)
		{
			propertyChangeSupport.removePropertyChangeListener(listener);
		}

		public void removePropertyChangeListener(String propertyName, 
PropertyChangeListener listener)
		{
			propertyChangeSupport.removePropertyChangeListener(propertyName, 
listener);
		}

		protected void firePropertyChange(String propertyName, Object 
oldValue,	Object newValue) 
		{
			propertyChangeSupport.firePropertyChange(propertyName, oldValue, 
newValue);
		}
		
		public boolean isStale()
		{
			return false;
		}
	}

	private static class Month 
	{
		private String name;
		
		public Month(String name) 
		{
			this.name = name;
		}
		
		public String getName() 
		{
			return name;
		}
	
		public String toString()
		{
			return "month:" + name;
		}
	}
	
	static class Person extends AbstractModelObject 
	{
		String 	name 	= "John Smith";
		Month 	month	= null;

		public Person(String name, Month month) 
		{
			this.name 	= name;
			this.month 	= month;
		}

		public String getName() 
		{
			return name;
		}

		public void setName( String name ) 
		{
			String oldValue = this.name;
			this.name = name;
			firePropertyChange("name", oldValue, name);
		}

		public Month getMonth() 
		{
			return month;
		}
		
		public void setMonth( Month month ) 
		{
			Month oldValue = this.month;
			this.month = month;
			firePropertyChange( "month", oldValue, month );
		}
		
		public String toString()
		{
			return "[Person] name:" + name + ", " + month.toString();
		}
	}

	static class View 
	{
		public Shell createShell() 
		{
			Display 			display 		= Display.getDefault();
			Shell 				shell 			= new Shell(display);
			DataBindingContext 	bindingContext 	= new DataBindingContext();
			
			shell.setLayout( new FillLayout(SWT.VERTICAL) );
			
			bindGUI(bindingContext);

			shell.open();
			return shell;
		}

		protected void bindGUI(DataBindingContext bindingContext)
		{
			IObservableList sourceObservableList = new WritableList();
			IObservableList targetObservableList = new WritableList();
			
			Person stephane = new Person( "Brad", 	new Month("23") );
			Person sylvain 	= new Person( "Rod", 	new Month("18") );
			Person marc 	= new Person( "Jack", 	new Month("8") );
			
			sourceObservableList.add( stephane );
			sourceObservableList.add( sylvain );
			sourceObservableList.add( marc );
			
			bindingContext.bindList	(	targetObservableList,
										sourceObservableList,
										null,
										null );
			
			targetObservableList.addListChangeListener( new ListChangeListener() );
			targetObservableList.addChangeListener( new ChangeListener() );
			
			stephane.setMonth( new Month("50") );
			
			System.out.println( targetObservableList );
		}
		
		class ListChangeListener implements IListChangeListener
		{
			public void handleListChange( ListChangeEvent event )
			{
				System.out.println("List change!");
			}
		}
		
		class ChangeListener implements IChangeListener
		{
			public void handleChange( ChangeEvent event )
			{
				System.out.println("Change!");
			}
		}
	}
}