SharedImages.java

/*******************************************************************************
 * Copyright (c) 2007, 2014 compeople AG 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:
 *    compeople AG - initial API and implementation
 *******************************************************************************/
package org.eclipse.riena.internal.ui.ridgets.swt;

import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.jface.resource.ImageRegistry;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Image;

import org.eclipse.riena.ui.swt.lnf.LnfKeyConstants;
import org.eclipse.riena.ui.swt.lnf.LnfManager;

/**
 * Provides access to a set of shared images. The images can be accessed using one of the predifined string constants.
 * <p>
 * Example:
 * 
 * <pre>
 * Image image = Activator.getSharedImage(SharedImages.IMG_LEAF);
 * </pre>
 * 
 * @see Activator
 */
public final class SharedImages {

	/**
	 * Collapsed icon used in trees.
	 */
	public static final String IMG_NODE_COLLAPSED = "IMG_NODE_COLLAPSED"; //$NON-NLS-1$
	/**
	 * Expanded icon used in trees.
	 */
	public static final String IMG_NODE_EXPANDED = "IMG_NODE_EXPANDED"; //$NON-NLS-1$
	/**
	 * Lead icon used in trees.
	 */
	public static final String IMG_LEAF = "IMG_LEAF"; //$NON-NLS-1$
	/**
	 * Checked check box image.
	 */
	public static final String IMG_CHECKED = "IMG_CHECKED"; //$NON-NLS-1$
	/**
	 * Unchecked check box image.
	 */
	public static final String IMG_UNCHECKED = "IMG_UNCHECKED"; //$NON-NLS-1$
	/**
	 * Error decoration for markers.
	 */
	public static final String IMG_ERROR_DECO = "IMG_ERROR_DECO"; //$NON-NLS-1$

	static void initializeImageRegistry(final ImageRegistry reg) {
		doPut(reg, IMG_NODE_COLLAPSED, SharedImages.class, "node_collapsed.gif"); //$NON-NLS-1$
		doPut(reg, IMG_NODE_EXPANDED, SharedImages.class, "node_expanded.gif"); //$NON-NLS-1$
		doPut(reg, IMG_LEAF, SharedImages.class, "leaf.gif"); //$NON-NLS-1$
		doPut(reg, IMG_CHECKED, SharedImages.class, "checkbox_checked.png"); //$NON-NLS-1$
		doPut(reg, IMG_UNCHECKED, SharedImages.class, "checkbox_unchecked.png"); //$NON-NLS-1$
		final Image lnfImage = getLnfImage(LnfKeyConstants.SUB_MODULE_TREE_ERROR_MARKER_ICON);
		if (lnfImage != null) {
			// create an independent copy so we can keep using it, even if  
			// lnfImage is disposed by the LnfManager. Note: if the L&F is  
			// changed later, we 'll still keep using our copy.
			final Image copy = new Image(lnfImage.getDevice(), lnfImage, SWT.IMAGE_COPY);
			reg.put(IMG_ERROR_DECO, copy);
		} else {
			doPut(reg, IMG_ERROR_DECO, SharedImages.class, "errorMarker.png"); //$NON-NLS-1$
		}
	}

	private SharedImages() {
		super();
	}

	// helping methods
	// ////////////////

	private static void doPut(final ImageRegistry reg, final String key, final Class<?> location, final String filename) {
		ImageDescriptor descr = ImageDescriptor.createFromFile(location, filename);
		if (descr == null) {
			descr = ImageDescriptor.getMissingImageDescriptor();
		}
		reg.put(key, descr);
	}

	private static Image getLnfImage(final String key) {
		Image result = null;
		if (Activator.getDefault() != null) { // running as plug-in
			result = LnfManager.getLnf().getImage(key);
		}
		return result;
	}

}