/**********************************************
* 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.impl;
import org.vectomatic.dom.svg.OMNode;
import org.vectomatic.dom.svg.OMSVGElement;
import org.vectomatic.dom.svg.utils.XPathPrefixResolver;
import com.google.gwt.core.client.JavaScriptObject;
import com.google.gwt.dom.client.Element;
import com.google.gwt.dom.client.NativeEvent;
import com.google.gwt.dom.client.Node;
import com.google.gwt.event.dom.client.LoseCaptureEvent;
import com.google.gwt.event.dom.client.LoseCaptureHandler;
import com.google.gwt.event.shared.HandlerRegistration;
/**
* Implementation class for low-level GWT integration
* (mostly event dispatching)
* @author laaglu
*/
public class DOMHelperImpl {
protected static boolean eventsInitialized;
protected OMSVGElement captureElt;
/**
* Initializes the event system. Positions event handlers
* on the window so that they can capture events early
* if necessary.
*/
protected native void initEventSystem() /*-{
$wnd.__helperImpl = this;
$wnd.__svgDispatch = function(evt) {
$wnd.__helperImpl.@org.vectomatic.dom.svg.impl.DOMHelperImpl::dispatch(Lcom/google/gwt/dom/client/NativeEvent;Lorg/vectomatic/dom/svg/OMNode;Lcom/google/gwt/dom/client/Element;)(evt, evt.currentTarget.__wrapper, evt.currentTarget);
};
$wnd.__svgCapture = function(evt) {
$wnd.__helperImpl.@org.vectomatic.dom.svg.impl.DOMHelperImpl::dispatchCapturedEvent(Lcom/google/gwt/dom/client/NativeEvent;Lcom/google/gwt/dom/client/Element;)(evt, evt.currentTarget);
};
$wnd.addEventListener('mousedown', $wnd.__svgCapture, true);
$wnd.addEventListener('mouseup', $wnd.__svgCapture, true);
$wnd.addEventListener('mousemove', $wnd.__svgCapture, true);
$wnd.addEventListener('mouseover', $wnd.__svgCapture, true);
$wnd.addEventListener('mouseout', $wnd.__svgCapture, true);
$wnd.addEventListener('mousewheel', $wnd.__svgCapture, true);
$wnd.addEventListener('click', $wnd.__svgCapture, true);
$wnd.addEventListener('focusin', $wnd.__svgCapture, true);
$wnd.addEventListener('focusout', $wnd.__svgCapture, true);
$wnd.addEventListener('activate', $wnd.__svgCapture, true);
$wnd.addEventListener('touchstart', $wnd.__svgCapture, true);
$wnd.addEventListener('touchend', $wnd.__svgCapture, true);
$wnd.addEventListener('touchmove', $wnd.__svgCapture, true);
$wnd.addEventListener('touchcancel', $wnd.__svgCapture, true);
$wnd.addEventListener('gesturestart', $wnd.__svgCapture, true);
$wnd.addEventListener('gesturechange', $wnd.__svgCapture, true);
$wnd.addEventListener('gestureend', $wnd.__svgCapture, true);
$wnd.addEventListener('dragstart', $wnd.__svgCapture, true);
$wnd.addEventListener('drag', $wnd.__svgCapture, true);
$wnd.addEventListener('dragenter', $wnd.__svgCapture, true);
$wnd.addEventListener('dragleave', $wnd.__svgCapture, true);
$wnd.addEventListener('dragover', $wnd.__svgCapture, true);
$wnd.addEventListener('drop', $wnd.__svgCapture, true);
$wnd.addEventListener('dragend', $wnd.__svgCapture, true);
}-*/;
protected void init() {
if (!eventsInitialized) {
eventsInitialized = true;
initEventSystem();
}
}
/**
* Makes a node sink the events emitted by the specified element
* @param elem The element emitting the events
* @param eventName The event name
*/
public void bindEventListener(Element elem, String eventName) {
init();
sinkEvents(elem, eventName);
}
/**
* Makes a node stop sinking the events emitted by the specified element
* @param elem The element emitting the events
* @param eventName The event name
*/
public void unbindEventListener(Element elem, String eventName) {
init();
unsinkEvents(elem, eventName);
}
/**
* Returns the element which currently captures all the
* events after a call to {@link org.vectomatic.dom.svg.impl.DOMHelperImpl#setCaptureElement(OMSVGElement, LoseCaptureHandler)}
* or null if element is set to capture events
* @return The event capturing element
*/
public OMSVGElement getCaptureElement() {
init();
return captureElt;
}
/**
* Makes the specified element capture all the events, until
* a call to {@link org.vectomatic.dom.svg.impl.DOMHelperImpl#releaseCaptureElement()}
* terminates the capture
* @param captureElt The capturing element
* @param loseCaptureHandler A handler which will be invoked
* if the element loses capture
* @return {@link HandlerRegistration} used to remove this handler
*/
public HandlerRegistration setCaptureElement(OMSVGElement captureElt, LoseCaptureHandler loseCaptureHandler) {
init();
this.captureElt = captureElt;
HandlerRegistration registration = null;
if (loseCaptureHandler != null) {
registration = captureElt.addHandler(loseCaptureHandler, LoseCaptureEvent.getType());
}
return registration;
}
/**
* Stops the forwarding of all events to the capturing element
* specified by {@link org.vectomatic.dom.svg.impl.DOMHelperImpl#setCaptureElement(OMSVGElement, LoseCaptureHandler)}
*/
public void releaseCaptureElement() {
init();
captureElt = null;
}
/**
* Activate the event listener for the specified
* event on an element
* @param elem The object which emits events
* @param eventName The event name
*/
protected native void sinkEvents(Element elem, String eventName) /*-{
elem.addEventListener(eventName, $wnd.__svgDispatch, false);
}-*/;
/**
* Deactivate the event listener for the specified
* event on an element
* @param elem The object which emits events
* @param eventName The event name
*/
protected native void unsinkEvents(Element elem, String eventName) /*-{
elem.removeEventListener(eventName, $wnd.__svgDispatch, false);
}-*/;
/**
* Central dispatching function for events emitted by DOM objects
* @param event The DOM event
* @param node The object processing the event
* @param elem The object emitting the event
*/
public void dispatch(NativeEvent event, OMNode node, Element elem) {
//Window.alert("type=" + event.getType());
String eventName = event.getType();
if ("mouseover".equals(eventName) || "mouseout".equals(eventName)) {
// Mouseover and mouseout deserve special treatment
// to solve issues described in:
// http://www.quirksmode.org/js/events_mouse.html
// For SVG, it seems better to test against the tree rooted at
// evt.currentTarget than againt the subtree rooted at evt.target
if (isChildOf((Node)event.getCurrentEventTarget().cast(), (Node)event.getRelatedEventTarget().cast())) {
return;
}
}
node.dispatch(event);
}
/**
* Dispatching function for events which result from a call
* to {@link #setCaptureElement(OMSVGElement, LoseCaptureHandler)}
* @param event The DOM event
* @param elem The object emitting the event
*/
public void dispatchCapturedEvent(NativeEvent event, Element elem) {
if (captureElt != null) {
String eventName = event.getType();
if ("loosecapture".equals(eventName)) {
captureElt = null;
}
dispatch(event, captureElt, elem);
event.stopPropagation();
}
}
/**
* Tests if a node is part of a DOM subtree.
* @param root
* The subtree root
* @param node
* The node to be tested
* @return
* True if the node is part of the subtree, false otherwise
*/
protected native boolean isChildOf(Node root, Node node) /*-{
while (node != null && node != root && node.nodeName != 'BODY') {
node= node.parentNode
}
if (node === root) {
return true;
}
return false;
}-*/;
///////////////////////////////////////////////////////////////
// XPath support
///////////////////////////////////////////////////////////////
public native JavaScriptObject evaluateNodeListXPath_(Element svgElement, String expr, XPathPrefixResolver resolver) /*-{
var result = svgElement.ownerDocument.evaluate(expr, svgElement, resolver ? function(prefix) { return resolver.@org.vectomatic.dom.svg.utils.XPathPrefixResolver::resolvePrefix(Ljava/lang/String;)(prefix); } : null, XPathResult.ORDERED_NODE_ITERATOR_TYPE , null);
return result;
}-*/;
public native Node evaluateNodeXPath_(Element svgElement, String expr, XPathPrefixResolver resolver) /*-{
var result = svgElement.ownerDocument.evaluate(expr, svgElement, resolver ? function(prefix) { return resolver.@org.vectomatic.dom.svg.utils.XPathPrefixResolver::resolvePrefix(Ljava/lang/String;)(prefix); } : null, XPathResult.ANY_UNORDERED_NODE_TYPE , null);
return result.singleNodeValue;
}-*/;
public native String evaluateStringXPath_(Element svgElement, String expr, XPathPrefixResolver resolver) /*-{
var result = svgElement.ownerDocument.evaluate(expr, svgElement, resolver ? function(prefix) { return resolver.@org.vectomatic.dom.svg.utils.XPathPrefixResolver::resolvePrefix(Ljava/lang/String;)(prefix); } : null, XPathResult.STRING_TYPE , null);
return result.stringValue;
}-*/;
public native float evaluateNumberXPath_(Element svgElement, String expr, XPathPrefixResolver resolver) /*-{
var result = svgElement.ownerDocument.evaluate(expr, svgElement, resolver ? function(prefix) { return resolver.@org.vectomatic.dom.svg.utils.XPathPrefixResolver::resolvePrefix(Ljava/lang/String;)(prefix); } : null, XPathResult.NUMBER_TYPE , null);
return result.numberValue;
}-*/;
public native boolean evaluateBooleanXPath_(Element svgElement, String expr, XPathPrefixResolver resolver) /*-{
var result = svgElement.ownerDocument.evaluate(expr, svgElement, resolver ? function(prefix) { return resolver.@org.vectomatic.dom.svg.utils.XPathPrefixResolver::resolvePrefix(Ljava/lang/String;)(prefix); } : null, XPathResult.BOOLEAN_TYPE , null);
return result.booleanValue;
}-*/;
}