/*
* Copyright 2008 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.dom.client;
/**
* Internet Explorer 6 implementation of
* {@link com.google.gwt.user.client.impl.DOMImpl}.
*/
class DOMImplIE6 extends DOMImplTrident {
private static boolean isIE6;
private static boolean isIE6Detected;
/**
* Check if the browser is IE6 or IE7.
*
* @return <code>true</code> if the browser is IE6, <code>false</code> if IE7
* or any other browser
*/
static boolean isIE6() {
if (!isIE6Detected) {
isIE6 = isIE6Impl();
isIE6Detected = true;
}
return isIE6;
}
// Stolen and modified from UsernmAgent.gwt.xml.
// TODO(jgw): Get rid of this method, and switch to using soft permutations
// once they land in trunk.
private static native boolean isIE6Impl() /*-{
function makeVersion(result) {
return (parseInt(result[1]) * 1000) + parseInt(result[2]);
}
var ua = navigator.userAgent.toLowerCase();
if (ua.indexOf("msie") != -1) {
var result = /msie ([0-9]+)\.([0-9]+)/.exec(ua);
if (result && result.length == 3) {
var v = makeVersion(result);
if (v < 7000) {
return true;
}
}
}
return false;
}-*/;
@Override
public native void cssClearOpacity(Style style) /*-{
style.filter = '';
}-*/;
@Override
public native void cssSetOpacity(Style style, double value) /*-{
style.filter = 'alpha(opacity=' + (value * 100) + ')';
}-*/;
@Override
public int getAbsoluteLeft(Element elem) {
Document doc = elem.getOwnerDocument();
return (int) Math.floor(getBoundingClientRectLeft(elem)
/ getZoomMultiple(doc) + doc.getScrollLeft());
}
@Override
public int getAbsoluteTop(Element elem) {
Document doc = elem.getOwnerDocument();
return (int) Math.floor(getBoundingClientRectTop(elem)
/ getZoomMultiple(doc) + doc.getScrollTop());
}
@Override
public int getScrollLeft(Element elem) {
if (isRTL(elem)) {
return super.getScrollLeft(elem) - (elem.getScrollWidth() - elem.getClientWidth());
}
return super.getScrollLeft(elem);
}
/*
* The src may not be set yet because of funky logic in setImgSrc(). See
* setImgSrc().
*/
@Override
public String imgGetSrc(Element img) {
if (isIE6()) {
return ImageSrcIE6.getImgSrc(img);
} else {
return super.imgGetSrc(img);
}
}
/**
* Works around an IE problem where multiple images trying to load at the same
* time will generate a request per image. We fix this by only allowing the
* first image of a given URL to set its source immediately, but simultaneous
* requests for the same URL don't actually get their source set until the
* original load is complete.
*/
@Override
public void imgSetSrc(Element img, String src) {
if (isIE6()) {
ImageSrcIE6.setImgSrc(img, src);
} else {
super.imgSetSrc(img, src);
}
}
@Override
public void setScrollLeft(Element elem, int left) {
if (isRTL(elem)) {
left += elem.getScrollWidth() - elem.getClientWidth();
}
super.setScrollLeft(elem, left);
}
/**
* Get the zoom multiple based on the current IE zoom level. A multiple of 2.0
* means that the user has zoomed in to 200%.
*
* @return the zoom multiple
*/
private double getZoomMultiple(Document doc) {
if (doc.getCompatMode().equals("CSS1Compat")) {
return 1;
} else {
// TODO(FINDBUGS): is integer division correct?
int bodyOffset = doc.getBody().getOffsetWidth();
return bodyOffset == 0 ? 1
: doc.getBody().getParentElement().getOffsetWidth() / bodyOffset;
}
}
}