Index: src/org/eclipse/jface/databinding/dialog/DialogPageSupport.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jface.databinding/src/org/eclipse/jface/databinding/dialog/DialogPageSupport.java,v
retrieving revision 1.2
diff -u -r1.2 DialogPageSupport.java
--- src/org/eclipse/jface/databinding/dialog/DialogPageSupport.java	23 Oct 2008 17:47:08 -0000	1.2
+++ src/org/eclipse/jface/databinding/dialog/DialogPageSupport.java	22 Jan 2009 21:04:19 -0000
@@ -15,21 +15,13 @@
 
 package org.eclipse.jface.databinding.dialog;
 
-import java.util.Iterator;
-
 import org.eclipse.core.databinding.AggregateValidationStatus;
 import org.eclipse.core.databinding.DataBindingContext;
-import org.eclipse.core.databinding.ValidationStatusProvider;
+import org.eclipse.core.databinding.TargetsListener;
 import org.eclipse.core.databinding.observable.ChangeEvent;
 import org.eclipse.core.databinding.observable.IChangeListener;
-import org.eclipse.core.databinding.observable.IObservable;
 import org.eclipse.core.databinding.observable.IStaleListener;
 import org.eclipse.core.databinding.observable.StaleEvent;
-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.ListDiff;
-import org.eclipse.core.databinding.observable.list.ListDiffEntry;
 import org.eclipse.core.databinding.observable.value.IObservableValue;
 import org.eclipse.core.databinding.observable.value.IValueChangeListener;
 import org.eclipse.core.databinding.observable.value.ValueChangeEvent;
@@ -68,55 +60,9 @@
 	private DataBindingContext dbc;
 	private IObservableValue aggregateStatus;
 	private boolean uiChanged = false;
-	private IChangeListener uiChangeListener = new IChangeListener() {
-		public void handleChange(ChangeEvent event) {
-			handleUIChanged();
-		}
-	};
-	private IListChangeListener validationStatusProvidersListener = new IListChangeListener() {
-		public void handleListChange(ListChangeEvent event) {
-			ListDiff diff = event.diff;
-			ListDiffEntry[] differences = diff.getDifferences();
-			for (int i = 0; i < differences.length; i++) {
-				ListDiffEntry listDiffEntry = differences[i];
-				ValidationStatusProvider validationStatusProvider = (ValidationStatusProvider) listDiffEntry
-						.getElement();
-				IObservableList targets = validationStatusProvider.getTargets();
-				if (listDiffEntry.isAddition()) {
-					targets
-							.addListChangeListener(validationStatusProviderTargetsListener);
-					for (Iterator it = targets.iterator(); it.hasNext();) {
-						((IObservable) it.next())
-								.addChangeListener(uiChangeListener);
-					}
-				} else {
-					targets
-							.removeListChangeListener(validationStatusProviderTargetsListener);
-					for (Iterator it = targets.iterator(); it.hasNext();) {
-						((IObservable) it.next())
-								.removeChangeListener(uiChangeListener);
-					}
-				}
-			}
-		}
-	};
-	private IListChangeListener validationStatusProviderTargetsListener = new IListChangeListener() {
-		public void handleListChange(ListChangeEvent event) {
-			ListDiff diff = event.diff;
-			ListDiffEntry[] differences = diff.getDifferences();
-			for (int i = 0; i < differences.length; i++) {
-				ListDiffEntry listDiffEntry = differences[i];
-				IObservable target = (IObservable) listDiffEntry.getElement();
-				if (listDiffEntry.isAddition()) {
-					target.addChangeListener(uiChangeListener);
-				} else {
-					target.removeChangeListener(uiChangeListener);
-				}
-			}
-		}
-	};
 	protected IStatus currentStatus;
 	protected boolean currentStatusStale;
+	private TargetsListener targetsListener;
 
 	/**
 	 * @param dialogPage
@@ -161,19 +107,11 @@
 		currentStatus = (IStatus) aggregateStatus.getValue();
 		currentStatusStale = aggregateStatus.isStale();
 		handleStatusChanged();
-		dbc.getValidationStatusProviders().addListChangeListener(
-				validationStatusProvidersListener);
-		for (Iterator it = dbc.getValidationStatusProviders().iterator(); it
-				.hasNext();) {
-			ValidationStatusProvider validationStatusProvider = (ValidationStatusProvider) it
-					.next();
-			IObservableList targets = validationStatusProvider.getTargets();
-			targets
-					.addListChangeListener(validationStatusProviderTargetsListener);
-			for (Iterator iter = targets.iterator(); iter.hasNext();) {
-				((IObservable) iter.next()).addChangeListener(uiChangeListener);
+		targetsListener = TargetsListener.listenOnce(dbc, new IChangeListener() {
+			public void handleChange(ChangeEvent event) {
+				handleUIChanged();
 			}
-		}
+		});
 	}
 
 	/**
@@ -184,20 +122,6 @@
 		if (currentStatus != null) {
 			handleStatusChanged();
 		}
-		dbc.getValidationStatusProviders().removeListChangeListener(
-				validationStatusProvidersListener);
-		for (Iterator it = dbc.getValidationStatusProviders().iterator(); it
-				.hasNext();) {
-			ValidationStatusProvider validationStatusProvider = (ValidationStatusProvider) it
-					.next();
-			IObservableList targets = validationStatusProvider.getTargets();
-			targets
-					.removeListChangeListener(validationStatusProviderTargetsListener);
-			for (Iterator iter = targets.iterator(); iter.hasNext();) {
-				((IObservable) iter.next())
-						.removeChangeListener(uiChangeListener);
-			}
-		}
 	}
 
 	/**
@@ -298,26 +222,10 @@
 	public void dispose() {
 		aggregateStatus.dispose();
 		if (!uiChanged) {
-			for (Iterator it = dbc.getValidationStatusProviders().iterator(); it
-					.hasNext();) {
-				ValidationStatusProvider validationStatusProvider = (ValidationStatusProvider) it
-						.next();
-				IObservableList targets = validationStatusProvider.getTargets();
-				targets
-						.removeListChangeListener(validationStatusProviderTargetsListener);
-				for (Iterator iter = targets.iterator(); iter.hasNext();) {
-					((IObservable) iter.next())
-							.removeChangeListener(uiChangeListener);
-				}
-			}
-			dbc.getValidationStatusProviders().removeListChangeListener(
-					validationStatusProvidersListener);
+			targetsListener.dispose();
 		}
 		aggregateStatus = null;
 		dbc = null;
-		uiChangeListener = null;
-		validationStatusProvidersListener = null;
-		validationStatusProviderTargetsListener = null;
 		dialogPage = null;
 	}
 }