/*******************************************************************************
* Copyright (c) 2005, 2009 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
* Brad Reynolds - bugs 164653, 147515
* Ovidio Mallo - bug 241318
* Matthew Hall - bugs 247875, 246782, 249526, 268022, 251424
*******************************************************************************/
package org.eclipse.core.internal.databinding.observable.masterdetail;
import org.eclipse.core.databinding.observable.Diffs;
import org.eclipse.core.databinding.observable.DisposeEvent;
import org.eclipse.core.databinding.observable.IDisposeListener;
import org.eclipse.core.databinding.observable.IObserving;
import org.eclipse.core.databinding.observable.ObservableTracker;
import org.eclipse.core.databinding.observable.masterdetail.IObservableFactory;
import org.eclipse.core.databinding.observable.value.AbstractObservableValue;
import org.eclipse.core.databinding.observable.value.IObservableValue;
import org.eclipse.core.databinding.observable.value.IValueChangeListener;
import org.eclipse.core.databinding.observable.value.ValueChangeEvent;
import org.eclipse.core.runtime.Assert;
/**
* @since 1.0
*
*/
public class DetailObservableValue extends AbstractObservableValue implements
IObserving {
private boolean updating = false;
private IValueChangeListener innerChangeListener = new IValueChangeListener() {
public void handleValueChange(ValueChangeEvent event) {
if (!updating) {
fireValueChange(event.diff);
}
}
};
private Object currentOuterValue;
private IObservableValue innerObservableValue;
private Object detailType;
private IObservableValue outerObservableValue;
private IObservableFactory factory;
/**
* @param outerObservableValue
* @param factory
* @param detailType
*/
public DetailObservableValue(IObservableValue outerObservableValue,
IObservableFactory factory, Object detailType) {
super(outerObservableValue.getRealm());
Assert.isTrue(!outerObservableValue.isDisposed(),
"Master observable is disposed"); //$NON-NLS-1$
this.factory = factory;
this.detailType = detailType;
this.outerObservableValue = outerObservableValue;
outerObservableValue.addDisposeListener(new IDisposeListener() {
public void handleDispose(DisposeEvent staleEvent) {
dispose();
}
});
ObservableTracker.setIgnore(true);
try {
updateInnerObservableValue();
} finally {
ObservableTracker.setIgnore(false);
}
outerObservableValue.addValueChangeListener(outerChangeListener);
}
IValueChangeListener outerChangeListener = new IValueChangeListener() {
public void handleValueChange(ValueChangeEvent event) {
if (isDisposed())
return;
ObservableTracker.setIgnore(true);
try {
Object oldValue = doGetValue();
updateInnerObservableValue();
fireValueChange(Diffs.createValueDiff(oldValue, doGetValue()));
} finally {
ObservableTracker.setIgnore(false);
}
}
};
private void updateInnerObservableValue() {
currentOuterValue = outerObservableValue.getValue();
if (innerObservableValue != null) {
innerObservableValue.removeValueChangeListener(innerChangeListener);
innerObservableValue.dispose();
}
if (currentOuterValue == null) {
innerObservableValue = null;
} else {
ObservableTracker.setIgnore(true);
try {
innerObservableValue = (IObservableValue) factory
.createObservable(currentOuterValue);
} finally {
ObservableTracker.setIgnore(false);
}
DetailObservableHelper.warnIfDifferentRealms(getRealm(),
innerObservableValue.getRealm());
if (detailType != null) {
Object innerValueType = innerObservableValue.getValueType();
Assert
.isTrue(
detailType.equals(innerValueType),
"Cannot change value type in a nested observable value, from " + innerValueType + " to " + detailType); //$NON-NLS-1$ //$NON-NLS-2$
}
innerObservableValue.addValueChangeListener(innerChangeListener);
}
}
public void doSetValue(final Object value) {
if (innerObservableValue != null) {
ObservableTracker.setIgnore(true);
try {
innerObservableValue.setValue(value);
} finally {
ObservableTracker.setIgnore(false);
}
}
}
public Object doGetValue() {
if (innerObservableValue == null)
return null;
ObservableTracker.setIgnore(true);
try {
return innerObservableValue.getValue();
} finally {
ObservableTracker.setIgnore(false);
}
}
public Object getValueType() {
return detailType;
}
public synchronized void dispose() {
super.dispose();
if (outerObservableValue != null) {
outerObservableValue.removeValueChangeListener(outerChangeListener);
}
if (innerObservableValue != null) {
innerObservableValue.removeValueChangeListener(innerChangeListener);
innerObservableValue.dispose();
}
outerObservableValue = null;
outerChangeListener = null;
currentOuterValue = null;
factory = null;
innerObservableValue = null;
innerChangeListener = null;
}
public Object getObserved() {
if (innerObservableValue instanceof IObserving) {
return ((IObserving) innerObservableValue).getObserved();
}
return null;
}
}