| /******************************************************************************* |
| * Copyright (c) 2009, 2017 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 |
| * Matthew Hall - initial API and implementation |
| * Lars Vogel <Lars.Vogel@gmail.com> - Bug 440810 |
| * Sergey Prigogin (Google) |
| *******************************************************************************/ |
| package org.eclipse.ui.databinding; |
| |
| import org.eclipse.core.databinding.observable.Diffs; |
| import org.eclipse.core.databinding.observable.IObservable; |
| import org.eclipse.core.databinding.observable.Realm; |
| import org.eclipse.core.databinding.observable.value.AbstractObservableValue; |
| import org.eclipse.core.databinding.observable.value.ComputedValue; |
| import org.eclipse.core.databinding.observable.value.IObservableValue; |
| import org.eclipse.core.runtime.Assert; |
| import org.eclipse.core.runtime.IAdapterManager; |
| import org.eclipse.core.runtime.Platform; |
| import org.eclipse.ui.IEditorInput; |
| import org.eclipse.ui.IEditorPart; |
| import org.eclipse.ui.IEditorReference; |
| import org.eclipse.ui.IPageListener; |
| import org.eclipse.ui.IPartListener2; |
| import org.eclipse.ui.IPartService; |
| import org.eclipse.ui.IPropertyListener; |
| import org.eclipse.ui.ISelectionService; |
| import org.eclipse.ui.IWindowListener; |
| import org.eclipse.ui.IWorkbench; |
| import org.eclipse.ui.IWorkbenchPage; |
| import org.eclipse.ui.IWorkbenchPartConstants; |
| import org.eclipse.ui.IWorkbenchPartReference; |
| import org.eclipse.ui.IWorkbenchWindow; |
| import org.eclipse.ui.services.IServiceLocator; |
| |
| /** |
| * Factory methods for creating observables for Workbench objects |
| * |
| * @since 3.5 |
| */ |
| public class WorkbenchObservables { |
| /** |
| * Returns an observable with values of the given target type. If the |
| * wrapped observable's value is of the target type, or can be adapted to |
| * the target type, this is taken as the value of the returned observable, |
| * otherwise <code>null</code>. |
| * |
| * @param master |
| * the observable whose value should be adapted |
| * @param adapter |
| * the target type |
| * @return an observable with values of the given type, or <code>null</code> |
| * if the current value of the given observable does not adapt to |
| * the target type |
| */ |
| public static <T> IObservableValue<T> observeDetailAdaptedValue(IObservableValue<?> master, Class<T> adapter) { |
| return observeDetailAdaptedValue(master, adapter, Platform |
| .getAdapterManager()); |
| } |
| |
| /** |
| * Returns an observable with values of the given target type. If the |
| * wrapped observable's value is of the target type, or can be adapted to |
| * the target type, this is taken as the value of the returned observable, |
| * otherwise <code>null</code>. |
| * |
| * @param master |
| * the observable whose value should be adapted |
| * @param adapter |
| * the target type |
| * @param adapterManager |
| * the adapter manager used to adapt the master value |
| * @return an observable with values of the given type, or <code>null</code> |
| * if the current value of the given observable does not adapt to |
| * the target type |
| */ |
| static <T> IObservableValue<T> observeDetailAdaptedValue(IObservableValue<?> master, Class<T> adapter, |
| IAdapterManager adapterManager) { |
| return WorkbenchProperties.adaptedValue(adapter, adapterManager) |
| .observeDetail(master); |
| } |
| |
| /** |
| * Returns an observable value that tracks the post selection of a selection |
| * service obtained through the given service locator, and adapts the first |
| * element of that selection to the given target type. |
| * <p> |
| * This method can be used by view or editor implementers to tie into the |
| * selection service, for example as follows: |
| * |
| * <pre> |
| * IObservableValue<IResource> selection = WorkbenchObservables.observeAdaptedSingleSelection(getSite(), |
| * IResource.class); |
| * </pre> |
| * |
| * </p> |
| * |
| * @param locator |
| * a service locator with an available {@link ISelectionService} |
| * @param targetType |
| * the target type |
| * @return an observable value whose value type is the given target type |
| */ |
| public static <T> IObservableValue<T> observeAdaptedSingleSelection(IServiceLocator locator, Class<T> targetType) { |
| ISelectionService selectionService = locator.getService(ISelectionService.class); |
| Assert.isNotNull(selectionService); |
| return WorkbenchProperties.singleSelection(null, true).value( |
| WorkbenchProperties.adaptedValue(targetType)).observe( |
| selectionService); |
| } |
| |
| /** |
| * Returns an observable value that tracks the active workbench window for |
| * the given workbench. |
| * |
| * @param workbench |
| * the workbench to get the observable for |
| * @return an observable value that tracks the active workbench window |
| * @since 3.110 |
| */ |
| public static IObservableValue<IWorkbenchWindow> observeActiveWorkbenchWindow(IWorkbench workbench) { |
| Assert.isNotNull(workbench); |
| return new ListeningValue<IWorkbenchWindow>() { |
| private final IWindowListener listener = new IWindowListener() { |
| @Override |
| public void windowActivated(IWorkbenchWindow window) { |
| protectedSetValue(window); |
| } |
| |
| @Override |
| public void windowDeactivated(IWorkbenchWindow window) { |
| if (window == doGetValue()) { |
| protectedSetValue(null); |
| } |
| } |
| |
| @Override |
| public void windowClosed(IWorkbenchWindow window) { |
| } |
| |
| @Override |
| public void windowOpened(IWorkbenchWindow window) { |
| } |
| }; |
| |
| @Override |
| protected void startListening() { |
| workbench.addWindowListener(listener); |
| } |
| |
| @Override |
| protected void stopListening() { |
| workbench.removeWindowListener(listener); |
| } |
| |
| @Override |
| protected IWorkbenchWindow calculate() { |
| return workbench.getActiveWorkbenchWindow(); |
| } |
| }; |
| } |
| |
| /** |
| * Returns an observable value that tracks the active workbench page for the |
| * given workbench window. |
| * |
| * @param window |
| * the workbench window to get the observable for |
| * @return an observable value that tracks the active workbench page |
| * @since 3.110 |
| */ |
| public static IObservableValue<IWorkbenchPage> observeActiveWorkbenchPage(IWorkbenchWindow window) { |
| Assert.isNotNull(window); |
| return new ListeningValue<IWorkbenchPage>() { |
| private final IPageListener listener = new IPageListener() { |
| @Override |
| public void pageActivated(IWorkbenchPage page) { |
| protectedSetValue(page); |
| } |
| |
| @Override |
| public void pageClosed(IWorkbenchPage page) { |
| if (page == doGetValue()) { |
| protectedSetValue(null); |
| } |
| } |
| |
| @Override |
| public void pageOpened(IWorkbenchPage page) { |
| } |
| }; |
| |
| @Override |
| protected void startListening() { |
| window.addPageListener(listener); |
| } |
| |
| @Override |
| protected void stopListening() { |
| window.removePageListener(listener); |
| } |
| |
| @Override |
| protected IWorkbenchPage calculate() { |
| return window.getActivePage(); |
| } |
| }; |
| } |
| |
| /** |
| * Returns an observable value that tracks the active workbench part for the |
| * given part service. |
| * |
| * @param partService |
| * the part service to get the observable for, e.g. a workbench |
| * page |
| * @return an observable value that tracks the active workbench part |
| * @since 3.110 |
| */ |
| public static IObservableValue<IWorkbenchPartReference> observeActivePart(IPartService partService) { |
| Assert.isNotNull(partService); |
| return new ListeningValue<IWorkbenchPartReference>() { |
| private final IPartListener2 listener = new IPartListener2() { |
| @Override |
| public void partActivated(IWorkbenchPartReference partRef) { |
| protectedSetValue(partRef); |
| } |
| |
| @Override |
| public void partDeactivated(IWorkbenchPartReference partRef) { |
| if (partRef == doGetValue()) { |
| protectedSetValue(null); |
| } |
| } |
| |
| @Override |
| public void partBroughtToTop(IWorkbenchPartReference partRef) { |
| } |
| |
| @Override |
| public void partClosed(IWorkbenchPartReference partRef) { |
| } |
| |
| @Override |
| public void partOpened(IWorkbenchPartReference partRef) { |
| } |
| |
| @Override |
| public void partHidden(IWorkbenchPartReference partRef) { |
| } |
| |
| @Override |
| public void partVisible(IWorkbenchPartReference partRef) { |
| } |
| |
| @Override |
| public void partInputChanged(IWorkbenchPartReference partRef) { |
| } |
| }; |
| |
| @Override |
| protected void startListening() { |
| partService.addPartListener(listener); |
| } |
| |
| @Override |
| protected void stopListening() { |
| partService.removePartListener(listener); |
| } |
| |
| @Override |
| protected IWorkbenchPartReference calculate() { |
| return partService.getActivePartReference(); |
| } |
| }; |
| } |
| |
| /** |
| * Returns an observable value that tracks the active editor for the given |
| * part service. |
| * |
| * @param partService |
| * the part service to get the observable for, e.g. a workbench |
| * page |
| * @return an observable value that tracks the active editor |
| * @since 3.110 |
| */ |
| public static IObservableValue<IEditorReference> observeActiveEditor(IPartService partService) { |
| final IObservableValue<IWorkbenchPartReference> partObservable = observeActivePart(partService); |
| return ComputedValue.create(() -> { |
| IWorkbenchPartReference value = partObservable.getValue(); |
| return value instanceof IEditorReference ? (IEditorReference) value : null; |
| }); |
| } |
| |
| /** |
| * Returns an observable value that tracks the editor input for the given |
| * editor. |
| * |
| * @param editor |
| * the editor to get the observable for |
| * @return an observable value that tracks the editor input |
| * @since 3.110 |
| */ |
| public static IObservableValue<IEditorInput> observeEditorInput(IEditorPart editor) { |
| Assert.isNotNull(editor); |
| return new ListeningValue<IEditorInput>() { |
| private final IPropertyListener listener = new IPropertyListener() { |
| @Override |
| public void propertyChanged(Object source, int propId) { |
| if (propId == IWorkbenchPartConstants.PROP_INPUT) { |
| protectedSetValue(editor.getEditorInput()); |
| } |
| } |
| }; |
| |
| @Override |
| protected void startListening() { |
| editor.addPropertyListener(listener); |
| } |
| |
| @Override |
| protected void stopListening() { |
| editor.removePropertyListener(listener); |
| } |
| |
| @Override |
| protected IEditorInput calculate() { |
| return editor.getEditorInput(); |
| } |
| }; |
| } |
| |
| /** |
| * A base class for creating observable values that track the state of a |
| * non-{@link IObservable} objects. |
| */ |
| private abstract static class ListeningValue<T> extends AbstractObservableValue<T> { |
| private T value; |
| private boolean isListening; |
| private volatile boolean hasListeners; |
| |
| @Override |
| protected final T doGetValue() { |
| // The value is not kept up to date when we are not listening. |
| if (isListening) { |
| return value; |
| } |
| return calculate(); |
| } |
| |
| /** |
| * Sets the value. Must be invoked in the {@link Realm} of the |
| * observable. Subclasses must call this method instead of |
| * {@link #setValue} or {@link #doSetValue}. |
| * |
| * @param value |
| * the value to set |
| */ |
| protected final void protectedSetValue(T value) { |
| checkRealm(); |
| if (!isListening) |
| throw new IllegalStateException(); |
| if (this.value != value) { |
| fireValueChange(Diffs.createValueDiff(this.value, this.value = value)); |
| } |
| } |
| |
| @Override |
| protected final void firstListenerAdded() { |
| if (getRealm().isCurrent()) { |
| startListeningInternal(); |
| } else { |
| getRealm().asyncExec(() -> { |
| if (hasListeners && !isListening) { |
| startListeningInternal(); |
| } |
| }); |
| } |
| hasListeners = true; |
| super.firstListenerAdded(); |
| } |
| |
| @Override |
| protected final void lastListenerRemoved() { |
| if (getRealm().isCurrent()) { |
| stopListeningInternal(); |
| } else { |
| getRealm().asyncExec(() -> { |
| if (!hasListeners && isListening) { |
| stopListeningInternal(); |
| } |
| }); |
| } |
| hasListeners = false; |
| super.lastListenerRemoved(); |
| } |
| |
| private void startListeningInternal() { |
| isListening = true; |
| value = calculate(); |
| startListening(); |
| } |
| |
| private void stopListeningInternal() { |
| isListening = false; |
| value = null; |
| stopListening(); |
| } |
| |
| /** |
| * Subclasses must override this method to attach listeners to the |
| * non-{@link IObservable} objects the state of which is tracked by this |
| * observable. |
| */ |
| protected abstract void startListening(); |
| |
| /** |
| * Subclasses must override this method to detach listeners from the |
| * non-{@link IObservable} objects the state of which is tracked by this |
| * observable. |
| */ |
| protected abstract void stopListening(); |
| |
| /** |
| * Subclasses must override this method to provide the object's value |
| * that will be used when the value is not set explicitly by |
| * {@link #doSetValue(Object)}. |
| * |
| * @return the object's value |
| */ |
| protected abstract T calculate(); |
| |
| @Override |
| public Object getValueType() { |
| return null; |
| } |
| } |
| } |