ExternalPageView.java

package kornell.gui.client.uidget;

import java.util.logging.Logger;

import com.google.gwt.core.client.Scheduler;
import com.google.gwt.dom.client.Document;
import com.google.gwt.dom.client.IFrameElement;
import com.google.gwt.event.logical.shared.ResizeEvent;
import com.google.gwt.event.logical.shared.ResizeHandler;
import com.google.gwt.place.shared.PlaceChangeEvent;
import com.google.gwt.user.client.Command;
import com.google.gwt.user.client.Event;
import com.google.gwt.user.client.EventListener;
import com.google.gwt.user.client.Window;
import com.google.gwt.user.client.ui.FlowPanel;

import kornell.api.client.KornellSession;
import kornell.core.lom.ExternalPage;
import kornell.core.util.StringUtils;
import kornell.gui.client.GenericClientFactoryImpl;
import kornell.gui.client.event.ShowChatDockEvent;
import kornell.gui.client.event.ShowChatDockEventHandler;
import kornell.gui.client.util.view.Positioning;

public class ExternalPageView extends Uidget implements ShowChatDockEventHandler{
	private static final Logger logger = Logger.getLogger(ExternalPageView.class.getName()); 
	private IFrameElement iframe;
	
	FlowPanel panel = new FlowPanel();
	private KornellSession session;

	public ExternalPageView(ExternalPage page) {
		GenericClientFactoryImpl.EVENT_BUS.addHandler(ShowChatDockEvent.TYPE,this);
		session = GenericClientFactoryImpl.KORNELL_SESSION;
		createIFrame();
		panel.setStyleName("contentWrapper");
		panel.getElement().appendChild(iframe);
		String url = page.getURL();
		String key = page.getKey();
		setSrc(url,key);
		initWidget(panel);

		GenericClientFactoryImpl.EVENT_BUS.addHandler(PlaceChangeEvent.TYPE, new PlaceChangeEvent.Handler() {
			@Override
			public void onPlaceChange(PlaceChangeEvent event) {
				placeIframe();
			}
		});
	}

	private void createIFrame() {
		if (iframe == null) {
			iframe = Document.get().createIFrameElement();
			iframe.addClassName("externalContent");
			iframe.setAttribute("allowtransparency", "true");
			iframe.setAttribute("style", "background-color: transparent;");
			//allowing html5 video player to work on fullscreen inside the iframe
			iframe.setAttribute("allowFullScreen", "true");
			iframe.setAttribute("webkitallowfullscreen", "true");
			iframe.setAttribute("mozallowfullscreen", "true");
			Event.sinkEvents(iframe, Event.ONLOAD);
			Event.setEventListener(iframe, new EventListener() {

				@Override
				public void onBrowserEvent(Event event) {
					fireViewReady();

				}
			});
		}
		placeIframe();

		// Weird yet simple way of solving FF's weird behavior
		Window.addResizeHandler(new ResizeHandler() {
			@Override
			public void onResize(ResizeEvent event) {
				Scheduler.get().scheduleDeferred(new Command() {
					@Override
					public void execute() {
						placeIframe();
					}
				});
			}
		});
	}

	private void placeIframe() {
		iframe.setPropertyString("width", "100%");
		int h = (Window.getClientHeight() - Positioning.NORTH_BAR);
		if(session.getCurrentCourseClass() != null && !session.getCurrentCourseClass().isEnrolledOnCourseVersion()){
			h -= Positioning.SOUTH_BAR;
		}
		String height = h + "px";
		iframe.setPropertyString("height", height);
	}

	public void setSrc(final String src, final String actomKey) {
		// TODO: Check if src exists
		String mkurl = StringUtils.mkurl("/", src);
		logger.info("Iframe source set to ["+mkurl+"]");
		iframe.setSrc(mkurl);
	}

	@Override
	public void onShowChatDock(ShowChatDockEvent event) {
		if(event.isShowChatDock()){
			panel.addStyleName("chatDocked");
		} else {
			panel.removeStyleName("chatDocked");
		}
	}

}