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view org.eclipse.jface.databinding/src/org/eclipse/jface/internal/databinding/viewers/ObservableCollectionContentProvider.d @ 125:c43718956f21 default tip
Updated the snippets status.
author | Jacob Carlborg <doob@me.com> |
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date | Thu, 11 Aug 2011 19:55:14 +0200 |
parents | 6be48cf9f95c |
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/******************************************************************************* * 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: * Matthew Hall - initial API and implementation (bug 215531) * Matthew Hall - bug 226765 ******************************************************************************/ module org.eclipse.jface.internal.databinding.viewers.ObservableCollectionContentProvider; import org.eclipse.jface.internal.databinding.viewers.ViewerUpdater; import org.eclipse.jface.internal.databinding.viewers.TableViewerUpdater; import org.eclipse.jface.internal.databinding.viewers.ListViewerUpdater; import org.eclipse.jface.internal.databinding.viewers.ObservableViewerElementSet; import java.lang.all; import org.eclipse.core.databinding.observable.IObservable; import org.eclipse.core.databinding.observable.IObservableCollection; import org.eclipse.core.databinding.observable.Observables; import org.eclipse.core.databinding.observable.Realm; import org.eclipse.core.databinding.observable.masterdetail.IObservableFactory; import org.eclipse.core.databinding.observable.masterdetail.MasterDetailObservables; import org.eclipse.core.databinding.observable.set.IObservableSet; import org.eclipse.core.databinding.observable.value.IObservableValue; import org.eclipse.core.databinding.observable.value.WritableValue; import org.eclipse.core.runtime.Assert; import org.eclipse.jface.databinding.swt.SWTObservables; import org.eclipse.jface.viewers.AbstractListViewer; import org.eclipse.jface.viewers.AbstractTableViewer; import org.eclipse.jface.viewers.IElementComparer; import org.eclipse.jface.viewers.IStructuredContentProvider; import org.eclipse.jface.viewers.StructuredViewer; import org.eclipse.jface.viewers.Viewer; import org.eclipse.swt.widgets.Display; /** * NON-API - Abstract base class for content providers where the viewer input is * expected to be an {@link IObservableCollection}. * * @since 1.2 */ public abstract class ObservableCollectionContentProvider : IStructuredContentProvider { private IObservableValue viewerObservable; /** * Element comparer used by the viewer (may be null). */ protected IElementComparer comparer; /** * Interface for sending updates to the viewer. */ protected ViewerUpdater viewerUpdater; /** * Observable set of all elements known to the content provider. Subclasses * must add new elements to this set <b>before</b> adding them to the * viewer, and must remove old elements from this set <b>after</b> removing * them from the viewer. */ protected IObservableSet knownElements; private IObservableSet unmodifiableKnownElements; private IObservableCollection observableCollection; /** * Constructs an ObservableCollectionContentProvider */ protected this() { final Realm realm = SWTObservables.getRealm(Display.getDefault()); viewerObservable = new WritableValue(realm); viewerUpdater = null; // Known elements is a detail set of viewerObservable, so that when we // get the viewer instance we can swap in a set that uses its // IElementComparer, if any. IObservableFactory knownElementsFactory = new class() IObservableFactory { public IObservable createObservable(Object target) { IElementComparer comparer = null; if (null !is cast(StructuredViewer)target) comparer = (cast(StructuredViewer) target).getComparer(); return ObservableViewerElementSet.withComparer(realm, null, comparer); } }; knownElements = MasterDetailObservables.detailSet(viewerObservable, knownElementsFactory, null); unmodifiableKnownElements = Observables .unmodifiableObservableSet(knownElements); observableCollection = null; } public Object[] getElements(Object inputElement) { if (observableCollection is null) return new Object[0]; return observableCollection.toArray(); } public void dispose() { if (observableCollection !is null) removeCollectionChangeListener(observableCollection); if (viewerObservable !is null) { viewerObservable.setValue(null); viewerObservable.dispose(); viewerObservable = null; } viewerUpdater = null; knownElements = null; unmodifiableKnownElements = null; } public void inputChanged(Viewer viewer, Object oldInput, Object newInput) { setViewer(viewer); setInput(newInput); } private void setViewer(Viewer viewer) { viewerUpdater = createViewerUpdater(viewer); comparer = getElementComparer(viewer); viewerObservable.setValue(viewer); // (clears knownElements) } private static IElementComparer getElementComparer(Viewer viewer) { if (null !is cast(StructuredViewer)viewer) return (cast(StructuredViewer) viewer).getComparer(); return null; } ViewerUpdater createViewerUpdater(Viewer viewer) { if (null !is cast(AbstractListViewer)viewer) return new ListViewerUpdater(cast(AbstractListViewer) viewer); if (null !is cast(AbstractTableViewer)viewer) return new TableViewerUpdater(cast(AbstractTableViewer) viewer); throw new IllegalArgumentException( "This content provider only works with AbstractTableViewer or AbstractListViewer"); //$NON-NLS-1$ } void setInput(Object input) { if (observableCollection !is null) { removeCollectionChangeListener(observableCollection); observableCollection = null; } if (input !is null) { checkInput(input); Assert.isTrue(null !is cast(IObservableCollection)input, "Input must be an IObservableCollection"); //$NON-NLS-1$ observableCollection = cast(IObservableCollection) input; addCollectionChangeListener(observableCollection); knownElements.addAll(observableCollection); } } /** * Throws an exception if the input is not the correct type. * * @param input * the input to check */ protected abstract void checkInput(Object input); /** * Register for change event notification from the given collection. * * @param collection * observable collection to listen to */ protected abstract void addCollectionChangeListener( IObservableCollection collection); /** * Deregisters from change events notification on the given collection. * * @param collection * observable collection to stop listening to */ protected abstract void removeCollectionChangeListener( IObservableCollection collection); /** * Returns whether the viewer is disposed. Collection change listeners in * subclasses should verify that the viewer is not disposed before sending * any updates to the {@link ViewerUpdater viewer updater}. * * @return whether the viewer is disposed. */ protected final bool isViewerDisposed() { Viewer viewer = cast(Viewer) viewerObservable.getValue(); return viewer is null || viewer.getControl() is null || viewer.getControl().isDisposed(); } /** * Returns the set of elements known to this content provider. Label * providers may track this set if they need to be notified about additions * before the viewer sees the added element, and notified about removals * after the element was removed from the viewer. This is intended for use * by label providers, as it will always return the items that need labels. * * @return unmodifiable observable set of items that will need labels */ public IObservableSet getKnownElements() { return unmodifiableKnownElements; } }