/*******************************************************************************
* Copyright (c) 2008 Matthew Hall 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
* (through WizardPageSupport.java)
* Matthew Hall - initial API and implementation (bug 239900)
* Matthew Hall - bug 237856
* Ovidio Mallo - bug 237856
******************************************************************************/
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.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;
import org.eclipse.core.databinding.util.Policy;
import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.MultiStatus;
import org.eclipse.core.runtime.Status;
import org.eclipse.jface.dialogs.DialogPage;
import org.eclipse.jface.dialogs.IMessageProvider;
/**
* Connects the validation result from the given data binding context to the
* given dialog page, updating the page's error message accordingly.
*
* @since 1.3
*/
public class DialogPageSupport {
/**
* Connect the validation result from the given data binding context to the
* given dialog page. The page's error message will not be set at time of
* creation, ensuring that the dialog page does not show an error right
* away. Upon any validation result change, the dialog page's error message
* will be updated according to the current validation result.
*
* @param wizardPage
* @param dbc
* @return an instance of WizardPageSupport
*/
public static DialogPageSupport create(DialogPage wizardPage,
DataBindingContext dbc) {
return new DialogPageSupport(wizardPage, dbc);
}
private DialogPage dialogPage;
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;
/**
* @param dialogPage
* @param dbc
* @noreference This constructor is not intended to be referenced by
* clients.
*/
protected DialogPageSupport(DialogPage dialogPage, DataBindingContext dbc) {
this.dialogPage = dialogPage;
this.dbc = dbc;
init();
}
/**
* @return the dialog page
* @noreference This method is not intended to be referenced by clients.
*/
protected DialogPage getDialogPage() {
return dialogPage;
}
/**
* @noreference This method is not intended to be referenced by clients.
*/
protected void init() {
aggregateStatus = new AggregateValidationStatus(dbc
.getValidationStatusProviders(),
AggregateValidationStatus.MAX_SEVERITY);
aggregateStatus.addValueChangeListener(new IValueChangeListener() {
public void handleValueChange(ValueChangeEvent event) {
currentStatus = (IStatus) event.diff.getNewValue();
currentStatusStale = aggregateStatus.isStale();
handleStatusChanged();
}
});
aggregateStatus.addStaleListener(new IStaleListener() {
public void handleStale(StaleEvent staleEvent) {
currentStatusStale = true;
handleStatusChanged();
}
});
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);
}
}
}
/**
* @noreference This method is not intended to be referenced by clients.
*/
protected void handleUIChanged() {
uiChanged = true;
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);
}
}
}
/**
* @noreference This method is not intended to be referenced by clients.
*/
protected void handleStatusChanged() {
if (currentStatus != null
&& currentStatus.getSeverity() == IStatus.ERROR) {
dialogPage.setMessage(null);
dialogPage.setErrorMessage(uiChanged ? currentStatus.getMessage()
: null);
if (currentStatusHasException()) {
handleStatusException();
}
} else if (currentStatus != null
&& currentStatus.getSeverity() != IStatus.OK) {
int severity = currentStatus.getSeverity();
int type;
switch (severity) {
case IStatus.OK:
type = IMessageProvider.NONE;
break;
case IStatus.CANCEL:
type = IMessageProvider.NONE;
break;
case IStatus.INFO:
type = IMessageProvider.INFORMATION;
break;
case IStatus.WARNING:
type = IMessageProvider.WARNING;
break;
case IStatus.ERROR:
type = IMessageProvider.ERROR;
break;
default:
Assert.isTrue(false, "incomplete switch statement"); //$NON-NLS-1$
return; // unreachable
}
dialogPage.setErrorMessage(null);
dialogPage.setMessage(currentStatus.getMessage(), type);
} else {
dialogPage.setMessage(null);
dialogPage.setErrorMessage(null);
}
}
private boolean currentStatusHasException() {
boolean hasException = false;
if (currentStatus.getException() != null) {
hasException = true;
}
if (currentStatus instanceof MultiStatus) {
MultiStatus multiStatus = (MultiStatus) currentStatus;
for (int i = 0; i < multiStatus.getChildren().length; i++) {
IStatus status = multiStatus.getChildren()[i];
if (status.getException() != null) {
hasException = true;
break;
}
}
}
return hasException;
}
/**
* @noreference This method is not intended to be referenced by clients.
*/
protected void handleStatusException() {
if (currentStatus.getException() != null) {
logThrowable(currentStatus.getException());
} else if (currentStatus instanceof MultiStatus) {
MultiStatus multiStatus = (MultiStatus) currentStatus;
for (int i = 0; i < multiStatus.getChildren().length; i++) {
IStatus status = multiStatus.getChildren()[i];
if (status.getException() != null) {
logThrowable(status.getException());
}
}
}
}
private void logThrowable(Throwable throwable) {
Policy
.getLog()
.log(
new Status(
IStatus.ERROR,
Policy.JFACE_DATABINDING,
IStatus.OK,
"Unhandled exception: " + throwable.getMessage(), throwable)); //$NON-NLS-1$
}
/**
* Disposes of this wizard page support object, removing any listeners it
* may have attached.
*/
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);
}
aggregateStatus = null;
dbc = null;
uiChangeListener = null;
validationStatusProvidersListener = null;
validationStatusProviderTargetsListener = null;
dialogPage = null;
}
}