com.google.gwt.sample.feedreader.client.EntryPanel.java Source code

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Here is the source code for com.google.gwt.sample.feedreader.client.EntryPanel.java

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/*
 * Copyright 2007 Google Inc.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */
package com.google.gwt.sample.feedreader.client;

import com.google.gwt.ajaxfeed.client.impl.EntryWrapper;
import com.google.gwt.user.client.Command;
import com.google.gwt.user.client.DOM;
import com.google.gwt.user.client.Element;
import com.google.gwt.user.client.History;
import com.google.gwt.user.client.Window;
import com.google.gwt.user.client.ui.FlowPanel;

/**
 * Displays a single entry in a feed.
 */
public class EntryPanel extends WallToWallPanel {
    final EntryWrapper entry;
    final PanelLabel panelLabel;
    final Configuration.Feed parentFeed;
    boolean contentsSet = false;

    public EntryPanel(final EntryWrapper entry, final Configuration.Feed parentFeed, WallToWallPanel parent) {
        super(entry.getTitle(), parent);
        addStyleName("EntryPanel");
        this.entry = entry;
        this.parentFeed = parentFeed;

        UnsunkLabel title = new UnsunkLabel(entry.getTitle());
        title.addStyleName("title");

        UnsunkLabel snippit = new UnsunkLabel(entry.getContentSnippet());
        snippit.addStyleName("snippit");

        FlowPanel vp = new FlowPanel();
        vp.add(title);
        vp.add(snippit);

        this.panelLabel = new PanelLabel(vp, new Command() {
            public void execute() {
                History.newItem(parentFeed.getUrl() + "||" + entry.getLink());
            }
        });
    }

    public void enter() {
        if (isAttached()) {
            return;
        }

        if (!contentsSet) {
            PanelLabel contents = new PanelLabel(entry.getContent(), null, true);
            retargetLinks(contents.getElement());
            contents.addStyleName("articleContents");
            add(contents);
            add(new PanelLabel("Open article", new Command() {
                public void execute() {
                    Window.open(entry.getLink(), "_blank", "");
                }
            }));
            contentsSet = true;
        }
        super.enter();
        History.newItem(parentFeed.getUrl() + "||" + entry.getLink());
    }

    public void exit() {
        // Dump the DOM elements on exit to avoid memory issues.
        clear();
        contentsSet = false;

        super.exit();
    }

    public PanelLabel getLabel() {
        return panelLabel;
    }

    protected String getShortTitle() {
        return "Entry";
    }

    /**
     * Force all links to open in a new window so that application state isn't
     * lost.
     * 
     * @param elt
     */
    protected void retargetLinks(Element elt) {
        int numChildren = DOM.getChildCount(elt);
        for (int i = 0; i < numChildren; i++) {
            Element child = DOM.getChild(elt, i);
            String href = DOM.getElementProperty(child, "href");
            if (href != null) {
                DOM.setElementAttribute(child, "onclick", "javascript:window.open('" + href + "', '_blank');");
                DOM.removeElementAttribute(child, "href");
                DOM.setElementAttribute(child, "class", "externalLink");
            }
            retargetLinks(child);
        }
    }
}