/**********************************************
* Copyright (C) 2010 Lukas Laag
* This file is part of lib-gwt-svg.
*
* libgwtsvg is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* libgwtsvg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with libgwtsvg. If not, see http://www.gnu.org/licenses/
**********************************************/
package org.vectomatic.dom.svg.utils;
import org.vectomatic.dom.svg.utils.DOMHelper;
import com.google.gwt.dom.client.Document;
import com.google.gwt.dom.client.Element;
import com.google.gwt.dom.client.IFrameElement;
import com.google.gwt.dom.client.NativeEvent;
import com.google.gwt.user.client.ui.RootPanel;
/**
* Implementation of the AsyncXmlLoader based on iframes.
*/
public class IFrameXmlLoader implements AsyncXmlLoader {
public IFrameXmlLoader() {
}
public void loadResource(String resourceName, AsyncXmlLoaderCallback callback) {
IFrameElement iframe = Document.get().createIFrameElement();
iframe.setAttribute("tabIndex", "-1");
iframe.setAttribute("style", "position: absolute; width: 0; height: 0; border: 0");
iframe.setAttribute("src", "javascript:''");
Element body = RootPanel.get().getElement();
body.appendChild(iframe);
setFrameLocation(resourceName, iframe, callback);
}
@SuppressWarnings("unused")
private void dispatch(NativeEvent event, AsyncXmlLoaderCallback callback) {
IFrameElement iframe = event.getCurrentEventTarget().cast();
if (iframe != null) {
String href = getHref(iframe);
if (!"about:blank".equals(href)) {
Element root = iframe.getContentDocument().getDocumentElement();
Element localRoot = DOMHelper.importNode(DOMHelper.getCurrentDocument(), root, true).cast();
callback.onSuccess(href, localRoot);
}
Element body = RootPanel.get().getElement();
body.removeChild(iframe);
}
}
private native String getHref(IFrameElement iframe) /*-{
return iframe.contentDocument.location.href;
}-*/;
private native void setFrameLocation(String resourceName, IFrameElement iframe, AsyncXmlLoaderCallback callback) /*-{
var gwtThis = this;
iframe.onload = function(evt) {
gwtThis.@org.vectomatic.dom.svg.utils.IFrameXmlLoader::dispatch(Lcom/google/gwt/dom/client/NativeEvent;Lorg/vectomatic/dom/svg/utils/AsyncXmlLoaderCallback;)(evt,callback);
}
iframe.contentDocument.location.href = resourceName;
}-*/;
}