Java tutorial
/******************************************************************************* * Copyright (c) 2000, 2006 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 *******************************************************************************/ package org.eclipse.ecf.internal.ui.wizards; import org.eclipse.core.runtime.Assert; import org.eclipse.core.runtime.IAdaptable; import org.eclipse.core.runtime.Platform; import org.eclipse.core.runtime.PlatformObject; import org.eclipse.jface.resource.ImageDescriptor; import org.eclipse.jface.viewers.DecoratingLabelProvider; import org.eclipse.jface.viewers.IColorProvider; import org.eclipse.jface.viewers.IFontProvider; import org.eclipse.jface.viewers.ILabelProvider; import org.eclipse.jface.viewers.LabelProvider; import org.eclipse.jface.viewers.LabelProviderChangedEvent; import org.eclipse.swt.graphics.Color; import org.eclipse.swt.graphics.Font; import org.eclipse.swt.graphics.FontData; import org.eclipse.swt.graphics.Image; import org.eclipse.swt.graphics.RGB; import org.eclipse.swt.widgets.Display; import org.eclipse.ui.IEditorRegistry; import org.eclipse.ui.IPropertyListener; import org.eclipse.ui.PlatformUI; import org.eclipse.ui.model.IWorkbenchAdapter; import org.eclipse.ui.model.IWorkbenchAdapter2; /** * Provides basic labels for adaptable objects that have the * <code>IWorkbenchAdapter</code> adapter associated with them. All dispensed * images are cached until the label provider is explicitly rootDisposed. This * class provides a facility for subclasses to define annotations on the labels * and icons of adaptable objects. */ public class WorkbenchLabelProvider extends LabelProvider implements IColorProvider, IFontProvider { /** * Returns a workbench label provider that is hooked up to the decorator * mechanism. * * @return a new <code>DecoratingLabelProvider</code> which wraps a <code> * new <code>WorkbenchLabelProvider</code> */ public static ILabelProvider getDecoratingWorkbenchLabelProvider() { return new DecoratingLabelProvider(new WorkbenchLabelProvider(), PlatformUI.getWorkbench().getDecoratorManager().getLabelDecorator()); } /** * Listener that tracks changes to the editor registry and does a full * update when it changes, since many workbench adapters derive their icon * from the file associations in the registry. */ private IPropertyListener editorRegistryListener = new IPropertyListener() { public void propertyChanged(Object source, int propId) { if (propId == IEditorRegistry.PROP_CONTENTS) { fireLabelProviderChanged(new LabelProviderChangedEvent(WorkbenchLabelProvider.this)); } } }; /** * Creates a new workbench label provider. */ public WorkbenchLabelProvider() { PlatformUI.getWorkbench().getEditorRegistry().addPropertyListener(editorRegistryListener); } /** * Returns an image descriptor that is based on the given descriptor, but * decorated with additional information relating to the state of the * provided object. * * Subclasses may reimplement this method to decorate an object's image. * * @param input * The base image to decorate. * @param element * The element used to look up decorations. * @return the resuling ImageDescriptor. * @see org.eclipse.jface.resource.CompositeImageDescriptor */ protected ImageDescriptor decorateImage(ImageDescriptor input, Object element) { return input; } /** * Returns a label that is based on the given label, but decorated with * additional information relating to the state of the provided object. * * Subclasses may implement this method to decorate an object's label. * * @param input * The base text to decorate. * @param element * The element used to look up decorations. * @return the resulting text */ protected String decorateText(String input, Object element) { return input; } /* * (non-Javadoc) Method declared on ILabelProvider */ public void dispose() { PlatformUI.getWorkbench().getEditorRegistry().removePropertyListener(editorRegistryListener); super.dispose(); } protected static final Object getAdapterUtil(Object sourceObject, Class adapterType) { Assert.isNotNull(adapterType); if (sourceObject == null) return null; if (adapterType.isInstance(sourceObject)) return sourceObject; if (sourceObject instanceof IAdaptable) { IAdaptable adaptable = (IAdaptable) sourceObject; Object result = adaptable.getAdapter(adapterType); if (result != null) { // Sanity-check Assert.isTrue(adapterType.isInstance(result)); return result; } } if (!(sourceObject instanceof PlatformObject)) { Object result = Platform.getAdapterManager().getAdapter(sourceObject, adapterType); if (result != null) return result; } return null; } /** * Returns the implementation of IWorkbenchAdapter for the given object. * * @param o * the object to look up. * @return IWorkbenchAdapter or<code>null</code> if the adapter is not * defined or the object is not adaptable. */ protected final IWorkbenchAdapter getAdapter(Object o) { return (IWorkbenchAdapter) getAdapterUtil(o, IWorkbenchAdapter.class); } /** * Returns the implementation of IWorkbenchAdapter2 for the given object. * * @param o * the object to look up. * @return IWorkbenchAdapter2 or<code>null</code> if the adapter is not * defined or the object is not adaptable. */ protected final IWorkbenchAdapter2 getAdapter2(Object o) { return (IWorkbenchAdapter2) getAdapterUtil(o, IWorkbenchAdapter2.class); } /* * (non-Javadoc) Method declared on ILabelProvider */ public final Image getImage(Object element) { // obtain the base image by querying the element IWorkbenchAdapter adapter = getAdapter(element); if (adapter == null) return null; ImageDescriptor descriptor = adapter.getImageDescriptor(element); if (descriptor == null) return null; // add any annotations to the image descriptor descriptor = decorateImage(descriptor, element); /* * Image image = (Image) * SWTResourceUtil.getImageTable().get(descriptor); if (image == null) { * image = descriptor.createImage(); * SWTResourceUtil.getImageTable().put(descriptor, image); } */ Image image = descriptor.createImage(); return image; } /* * (non-Javadoc) Method declared on ILabelProvider */ public final String getText(Object element) { // query the element for its label IWorkbenchAdapter adapter = getAdapter(element); if (adapter == null) return ""; //$NON-NLS-1$ String label = adapter.getLabel(element); // return the decorated label return decorateText(label, element); } /* * (non-Javadoc) * * @see org.eclipse.jface.viewers.IColorProvider#getForeground(java.lang.Object) */ public Color getForeground(Object element) { return getColor(element, true); } /* * (non-Javadoc) * * @see org.eclipse.jface.viewers.IColorProvider#getBackground(java.lang.Object) */ public Color getBackground(Object element) { return getColor(element, false); } /* * (non-Javadoc) * * @see org.eclipse.jface.viewers.IFontProvider#getFont(java.lang.Object) */ public Font getFont(Object element) { IWorkbenchAdapter2 adapter = getAdapter2(element); if (adapter == null) return null; FontData descriptor = adapter.getFont(element); if (descriptor == null) return null; /* * Font font = (Font) SWTResourceUtil.getFontTable().get(descriptor); if * (font == null) { font = new Font(Display.getCurrent(), descriptor); * SWTResourceUtil.getFontTable().put(descriptor, font); } */ Font font = new Font(Display.getCurrent(), descriptor); return font; } private Color getColor(Object element, boolean forground) { IWorkbenchAdapter2 adapter = getAdapter2(element); if (adapter == null) return null; RGB descriptor = forground ? adapter.getForeground(element) : adapter.getBackground(element); if (descriptor == null) return null; /* * Color color = (Color) * SWTResourceUtil.getColorTable().get(descriptor); if (color == null) { * color = new Color(Display.getCurrent(), descriptor); * SWTResourceUtil.getColorTable().put(descriptor, color); } */ Color color = new Color(Display.getCurrent(), descriptor); return color; } }