/*******************************************************************************
* Copyright (c) 2016 vogella GmbH 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:
* Simon Scholz <simon.scholz@vogella.com> - initial API and implementation
******************************************************************************/
package org.eclipse.jface.examples.databinding.snippets;
import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import org.eclipse.core.databinding.DataBindingContext;
import org.eclipse.core.databinding.UpdateValueStrategy;
import org.eclipse.core.databinding.ValidationStatusProvider;
import org.eclipse.core.databinding.beans.BeanProperties;
import org.eclipse.core.databinding.observable.Realm;
import org.eclipse.core.databinding.observable.list.IObservableList;
import org.eclipse.core.databinding.observable.sideeffect.ISideEffect;
import org.eclipse.core.databinding.observable.sideeffect.ISideEffectFactory;
import org.eclipse.core.databinding.observable.value.IObservableValue;
import org.eclipse.core.databinding.observable.value.WritableValue;
import org.eclipse.core.databinding.validation.ValidationStatus;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;
import org.eclipse.jface.databinding.fieldassist.ControlDecorationSupport;
import org.eclipse.jface.databinding.swt.DisplayRealm;
import org.eclipse.jface.databinding.swt.ISWTObservableValue;
import org.eclipse.jface.databinding.swt.WidgetProperties;
import org.eclipse.jface.databinding.swt.WidgetSideEffects;
import org.eclipse.jface.layout.GridLayoutFactory;
import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Text;
/**
* <p>
* This snippet shows how to migrate from the usage of the
* {@link DataBindingContext} to the {@link ISideEffect} approach.<br/>
* </p>
* <p>
* So basically two logically equal applications are implemented with the two
* different approaches. The two bindData() methods in the view implementations
* are the most interesting concerning the databinding migration.
* </p>
* <p>
* The "old" {@link DataBindingContext} approach is shown by the
* {@link ObservableBeanPerson} and {@link ObservableView} classes, and the
* {@link TrackedPerson} and {@link TrackedView} classes introduce the "new"
* {@link ISideEffect} approach.
* </p>
*
* @since 3.2
*
*/
public class SnippetSideEffectMigration {
public static void main(String[] args) {
Display display = new Display();
Realm.runWithDefault(DisplayRealm.getRealm(display), () -> {
// create the Person model object
ObservableBeanPerson observableBeanPerson = new ObservableBeanPerson();
Shell observableShell = new ObservableView(observableBeanPerson).createShell();
TrackedPerson trackedPerson = new TrackedPerson();
Shell trackedShell = new TrackedView(trackedPerson).createShell();
while (!observableShell.isDisposed() && !trackedShell.isDisposed()) {
if (!display.readAndDispatch()) {
display.sleep();
}
}
});
}
// Observable Person model
static class ObservableBeanPerson {
public static final String PROPERTY_FIRST_NAME = "firstName";
public static final String PROPERTY_LAST_NAME = "lastName";
private PropertyChangeSupport propertyChangeSupport = new PropertyChangeSupport(this);
private String firstName = "Simon";
private String lastName = "Scholz";
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
propertyChangeSupport.firePropertyChange(PROPERTY_FIRST_NAME, this.firstName, this.firstName = firstName);
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
propertyChangeSupport.firePropertyChange(PROPERTY_LAST_NAME, this.lastName, this.lastName = lastName);
}
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);
}
}
static class ObservableView {
private ObservableBeanPerson person;
private Text personFirstNameText;
private Text personLastNameText;
public ObservableView(ObservableBeanPerson person) {
this.person = person;
}
public Shell createShell() {
Display display = Display.getDefault();
Shell shell = new Shell(display);
shell.setText("DatabindingContext Sample");
new Label(shell, SWT.NONE).setText("First Name:");
personFirstNameText = new Text(shell, SWT.BORDER);
new Label(shell, SWT.NONE).setText("Last Name:");
personLastNameText = new Text(shell, SWT.BORDER);
bindData();
GridLayoutFactory.fillDefaults().numColumns(2).generateLayout(shell);
// Open and return the Shell
shell.pack();
shell.open();
return shell;
}
private void bindData() {
DataBindingContext dbc = new DataBindingContext();
IObservableValue personFirstNameObservable = BeanProperties.value(ObservableBeanPerson.PROPERTY_FIRST_NAME)
.observe(person);
ISWTObservableValue personFirstNameTextObservable = WidgetProperties.text(SWT.Modify)
.observe(personFirstNameText);
dbc.bindValue(personFirstNameTextObservable, personFirstNameObservable,
new UpdateValueStrategy().setAfterConvertValidator(obj -> {
if (obj instanceof String && ((String) obj).isEmpty()) {
return ValidationStatus.error("First Name may not be empty");
}
return Status.OK_STATUS;
}), null);
IObservableValue personLastNameObservable = BeanProperties.value(ObservableBeanPerson.PROPERTY_LAST_NAME)
.observe(person);
ISWTObservableValue personLastNameTextObservable = WidgetProperties.text(SWT.Modify)
.observe(personLastNameText);
dbc.bindValue(personLastNameTextObservable, personLastNameObservable,
new UpdateValueStrategy().setAfterConvertValidator(obj -> {
if (obj instanceof String && ((String) obj).isEmpty()) {
return ValidationStatus.error("Last Name may not be empty");
}
return Status.OK_STATUS;
}), null);
IObservableList<ValidationStatusProvider> validationStatusProviders = dbc.getValidationStatusProviders();
for (ValidationStatusProvider statusProvider : validationStatusProviders) {
ControlDecorationSupport.create(statusProvider, SWT.TOP | SWT.LEFT);
}
personFirstNameText.addDisposeListener(e -> dbc.dispose());
}
}
// Observable Person model
static class TrackedPerson {
private WritableValue<String> firstName = new WritableValue<>("Simon", String.class);
private WritableValue<String> lastName = new WritableValue<>("Scholz", String.class);
/**
* @return the person's first name
* @TrackedGetter
*/
public String getFirstName() {
return firstName.getValue();
}
/**
* @param firstName
* The first name to set.
*/
public void setFirstName(String firstName) {
this.firstName.setValue(firstName);
}
/**
* @return the person's last name.
* @TrackedGetter
*/
public String getLastName() {
return lastName.getValue();
}
/**
* @param lastName
* The last name to set.
*/
public void setLastName(String lastName) {
this.lastName.setValue(lastName);
}
}
static class TrackedView {
private TrackedPerson person;
private Text personFirstNameText;
private Text personLastNameText;
public TrackedView(TrackedPerson person) {
this.person = person;
}
public Shell createShell() {
Display display = Display.getDefault();
Shell shell = new Shell(display);
shell.setText("ISideEffect Sample");
new Label(shell, SWT.NONE).setText("First Name:");
personFirstNameText = new Text(shell, SWT.BORDER);
new Label(shell, SWT.NONE).setText("Last Name:");
personLastNameText = new Text(shell, SWT.BORDER);
bindData();
GridLayoutFactory.fillDefaults().numColumns(2).generateLayout(shell);
// Open and return the Shell
shell.pack();
shell.open();
return shell;
}
private void bindData() {
// create the observables, which should be bound by the SideEffect
ISWTObservableValue personFirstNameTextObservable = WidgetProperties.text(SWT.Modify)
.observe(personFirstNameText);
ISWTObservableValue personLastNameTextObservable = WidgetProperties.text(SWT.Modify)
.observe(personLastNameText);
ISideEffectFactory sideEffectFactory = WidgetSideEffects.createFactory(personFirstNameText);
sideEffectFactory.create(person::getFirstName, personFirstNameText::setText);
WritableValue<IStatus> firstNameValidation = new WritableValue<>();
sideEffectFactory.create(() -> {
String firstName = (String) personFirstNameTextObservable.getValue();
if (firstName != null && firstName.isEmpty()) {
firstNameValidation.setValue(ValidationStatus.error("First Name may not be empty"));
return;
}
person.setFirstName(firstName);
firstNameValidation.setValue(Status.OK_STATUS);
});
ControlDecorationSupport.create(firstNameValidation, SWT.TOP | SWT.LEFT, personFirstNameTextObservable);
sideEffectFactory.create(person::getLastName, personLastNameText::setText);
WritableValue<IStatus> lastNameValidation = new WritableValue<>();
sideEffectFactory.create(() -> {
String lastName = (String) personLastNameTextObservable.getValue();
if (lastName != null && lastName.isEmpty()) {
lastNameValidation.setValue(ValidationStatus.error("Last Name may not be empty"));
return;
}
person.setLastName(lastName);
lastNameValidation.setValue(Status.OK_STATUS);
});
ControlDecorationSupport.create(lastNameValidation, SWT.TOP | SWT.LEFT, personLastNameTextObservable);
}
}
}