org.eclipse.birt.chart.examples.view.util.UIHelper.java Source code

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Here is the source code for org.eclipse.birt.chart.examples.view.util.UIHelper.java

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/*******************************************************************************
 * Copyright (c) 2005 Actuate Corporation.
 * 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:
 *  Actuate Corporation  - initial API and implementation
 *******************************************************************************/

package org.eclipse.birt.chart.examples.view.util;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;

import org.eclipse.birt.chart.examples.ChartExamplesPlugin;
import org.eclipse.birt.chart.examples.radar.i18n.Messages;
import org.eclipse.core.runtime.Platform;
import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.jface.resource.ImageRegistry;
import org.eclipse.jface.resource.JFaceResources;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.widgets.Combo;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Display;

/**
 * This class has been created to hold methods that provide specific
 * functionality or services.
 */
public final class UIHelper {

    /**
     * This method returns an URL for a resource given its plugin relative path.
     * It is intended to be used to abstract out the usage of the UI as a plugin
     * or standalone component when it comes to accessing resources.
     * 
     * @param sPluginRelativePath
     *            The path to the resource relative to the plugin location.
     * @return URL representing the location of the resource.
     */
    public static URL getURL(String sPluginRelativePath) {
        URL url = null;
        if (Platform.getExtensionRegistry() != null) {
            try {
                url = new URL(ChartExamplesPlugin.getDefault().getBundle().getEntry("/"), sPluginRelativePath); //$NON-NLS-1$
            } catch (MalformedURLException e) {
                e.printStackTrace();
            }
        } else {
            try {
                url = new URL("file:///" + new File(sPluginRelativePath).getAbsolutePath()); //$NON-NLS-1$
            } catch (MalformedURLException e) {
                e.printStackTrace();
            }
        }

        return url;
    }

    private static Image createImage(String sPluginRelativePath) {
        Image img = null;
        try {
            try {
                img = new Image(Display.getCurrent(), getURL(sPluginRelativePath).openStream());
            } catch (MalformedURLException e1) {
                img = new Image(Display.getCurrent(), new FileInputStream(getURL(sPluginRelativePath).toString()));
            }
        } catch (IOException e) {
            e.printStackTrace();
        }

        // If still can't load, return a dummy image.
        if (img == null) {
            img = new Image(Display.getCurrent(), 1, 1);
        }
        return img;
    }

    /**
     * This is a convenience method to get an imgIcon from a URL.
     * 
     * @param sPluginRelativePath
     *            The URL for the imgIcon.
     * @return The imgIcon represented by the given URL.
     * @see #setImageCached( boolean )
     */
    public static Image getImage(String sPluginRelativePath) {
        ImageRegistry registry = JFaceResources.getImageRegistry();
        Image image = registry.get(sPluginRelativePath);
        if (image == null) {
            image = createImage(sPluginRelativePath);
            registry.put(sPluginRelativePath, image);
        }
        return image;
    }

    /**
     * This is a convenience method to get an imgIcon from a URL.
     * 
     * @param sPluginRelativePath
     *            The URL for the imgIcon.
     * @return The imgIcon represented by the given URL.
     * @see #setImageCached( boolean )
     */
    public static ImageDescriptor getImageDescriptor(String sPluginRelativePath) {
        ImageRegistry registry = JFaceResources.getImageRegistry();
        ImageDescriptor image = registry.getDescriptor(sPluginRelativePath);
        if (image == null) {
            registry.put(sPluginRelativePath, createImage(sPluginRelativePath));
            image = registry.getDescriptor(sPluginRelativePath);
        }
        return image;
    }

    /**
     * Returns i18n 'Auto' sting.
     * 
     * @return
     */
    public static String getAutoMessage() {
        return Messages.getString("ItemLabel.Auto"); //$NON-NLS-1$
    }
}