| /* Copyright (c) 2006-2010 by OpenLayers Contributors (see authors.txt for | |
| * full list of contributors). Published under the Clear BSD license. | |
| * See http://svn.openlayers.org/trunk/openlayers/license.txt for the | |
| * full text of the license. */ | |
| /** | |
| * @requires OpenLayers/Tile/Image.js | |
| */ | |
| /** | |
| * Class: OpenLayers.Tile.Image.IFrame | |
| * Instances of OpenLayers.Tile.Image.IFrame are used to manage the image tiles | |
| * used by Layer.WMS.Post loaded via HTTP-POST-protocol. Create a new image | |
| * tile with the <OpenLayers.Tile.Image.IFrame> constructor. | |
| * | |
| * Inherits from: | |
| * - <OpenLayers.Tile.Image> | |
| */ | |
| OpenLayers.Tile.Image.IFrame = OpenLayers.Class(OpenLayers.Tile.Image, { | |
| /** | |
| * Property: layerAlphaHack | |
| * {Boolean} Always false for an instance. | |
| */ | |
| /** | |
| * Constructor: OpenLayers.Tile.Image.IFrame | |
| * Constructor for a new <OpenLayers.Tile.Image.IFrame> instance. | |
| * | |
| * Parameters: | |
| * layer - {<OpenLayers.Layer>} layer that the tile will go in. | |
| * position - {<OpenLayers.Pixel>} | |
| * bounds - {<OpenLayers.Bounds>} | |
| * size - {<OpenLayers.Size>} | |
| */ | |
| initialize: function(layer, position, bounds, url, size) { | |
| OpenLayers.Tile.Image.prototype.initialize.apply(this, arguments); | |
| this.layerAlphaHack = false; | |
| }, | |
| /** | |
| * Method: destroy | |
| * nullify references to prevent circular references and memory leaks | |
| */ | |
| destroy: function() { | |
| if(this.imgDiv != null) { | |
| // unregister the "load" handler | |
| OpenLayers.Event.stopObservingElement(this.imgDiv.firstChild); | |
| } | |
| OpenLayers.Tile.Image.prototype.destroy.apply(this, arguments); | |
| }, | |
| /** | |
| * Method: clear | |
| * Removes the iframe from DOM (avoids back-button problems). | |
| */ | |
| clear: function() { | |
| if(this.imgDiv) { | |
| var iFrame = this.imgDiv.firstChild; | |
| OpenLayers.Event.stopObservingElement(iFrame); | |
| this.imgDiv.removeChild(iFrame); | |
| } | |
| }, | |
| /** | |
| * Method: clone | |
| * | |
| * Parameters: | |
| * obj - {<OpenLayers.Tile.Image.IFrame>} The tile to be cloned | |
| * | |
| * Returns: | |
| * {<OpenLayers.Tile.Image.IFrame>} An exact clone of this | |
| * <OpenLayers.Tile.Image.IFrame> | |
| */ | |
| clone: function (obj) { | |
| if (obj == null) { | |
| obj = new OpenLayers.Tile.Image.IFrame( | |
| this.layer, this.position, this.bounds, this.url, this.size); | |
| } | |
| //pick up properties from superclass | |
| obj = OpenLayers.Tile.Image.prototype.clone.apply(this, [obj]); | |
| return obj; | |
| }, | |
| /** | |
| * Method: renderTile | |
| */ | |
| renderTile: function() { | |
| if(OpenLayers.Tile.Image.prototype.renderTile.apply(this, arguments)) { | |
| // create a html form and add it temporary to the layer div | |
| var form = this.createRequestForm(); | |
| this.imgDiv.appendChild(form); | |
| // submit the form (means fetching the image) | |
| form.submit(); | |
| this.imgDiv.removeChild(form); | |
| } | |
| }, | |
| /** | |
| * Method: initImgDiv | |
| * Creates the imgDiv property on the tile. | |
| */ | |
| initImgDiv: function() { | |
| this.imgDiv = this.createImgDiv(); | |
| OpenLayers.Util.modifyDOMElement(this.imgDiv, this.id, null, | |
| this.layer.getImageSize(), "relative"); | |
| this.imgDiv.className = 'olTileImage'; | |
| this.frame.appendChild(this.imgDiv); | |
| this.layer.div.appendChild(this.frame); | |
| if(this.layer.opacity != null) { | |
| OpenLayers.Util.modifyDOMElement(this.imgDiv, null, null, null, | |
| null, null, null, | |
| this.layer.opacity); | |
| } | |
| // we need this reference to check back the viewRequestID | |
| this.imgDiv.map = this.layer.map; | |
| }, | |
| /** | |
| * Method: createImgDiv | |
| * Creates a div with iframe.and eventPane | |
| * | |
| * Returns: | |
| * {DOMElement} | |
| */ | |
| createImgDiv: function() { | |
| var eventPane = document.createElement("div"); | |
| if(OpenLayers.Util.getBrowserName() == "msie") { | |
| // IE cannot handle events on elements without backgroundcolor. So we | |
| // use this little hack to make elements transparent | |
| eventPane.style.backgroundColor = '#FFFFFF'; | |
| eventPane.style.filter = 'chroma(color=#FFFFFF)'; | |
| } | |
| OpenLayers.Util.modifyDOMElement(eventPane, null, | |
| new OpenLayers.Pixel(0,0), this.layer.getImageSize(), "absolute"); | |
| var imgDiv = document.createElement("div"); | |
| imgDiv.appendChild(eventPane); | |
| return imgDiv; | |
| }, | |
| /** | |
| * Method: createIFrame | |
| * Create the IFrame which shows the image. | |
| * | |
| * Returns: | |
| * {DOMElement} Iframe | |
| */ | |
| createIFrame: function() { | |
| var id = this.id+'_iFrame'; | |
| var iframe; | |
| if(OpenLayers.Util.getBrowserName() == "msie") { | |
| // InternetExplorer does not set the name attribute of an iFrame | |
| // properly via DOM manipulation, so we need to do it on our own with | |
| // this hack. | |
| iframe = document.createElement('<iframe name="'+id+'">'); | |
| // IFrames in InternetExplorer are not transparent, if you set the | |
| // backgroundColor transparent. This is a workarround to get | |
| // transparent iframes. | |
| iframe.style.backgroundColor = '#FFFFFF'; | |
| iframe.style.filter = 'chroma(color=#FFFFFF)'; | |
| } | |
| else { | |
| iframe = document.createElement('iframe'); | |
| iframe.style.backgroundColor = 'transparent'; | |
| // iframe.name needs to be an unique id, otherwise it | |
| // could happen that other iframes are overwritten. | |
| iframe.name = id; | |
| } | |
| iframe.id = id; | |
| // some special properties to avoid scaling the images and scrollbars | |
| // in the iframe | |
| iframe.scrolling = 'no'; | |
| iframe.marginWidth = '0px'; | |
| iframe.marginHeight = '0px'; | |
| iframe.frameBorder = '0'; | |
| OpenLayers.Util.modifyDOMElement(iframe, id, | |
| new OpenLayers.Pixel(0,0), this.layer.getImageSize(), "absolute"); | |
| //bind a listener to the onload of the iframe so that we | |
| // can register when a tile has finished loading. | |
| var onload = function() { | |
| this.show(); | |
| //normally isLoading should always be true here but there are some | |
| // right funky conditions where loading and then reloading a tile | |
| // with the same url *really*fast*. this check prevents sending | |
| // a 'loadend' if the msg has already been sent | |
| // | |
| if (this.isLoading) { | |
| this.isLoading = false; | |
| this.events.triggerEvent("loadend"); | |
| } | |
| }; | |
| OpenLayers.Event.observe(iframe, 'load', | |
| OpenLayers.Function.bind(onload, this)); | |
| return iframe; | |
| }, | |
| /** | |
| * Method: createRequestForm | |
| * Create the html <form> element with width, height, bbox and all | |
| * parameters specified in the layer params. | |
| * | |
| * Returns: | |
| * {DOMElement} The form element which sends the HTTP-POST request to the | |
| * WMS. | |
| */ | |
| createRequestForm: function() { | |
| // creation of the form element | |
| var form = document.createElement('form'); | |
| form.method = 'POST'; | |
| var cacheId = this.layer.params["_OLSALT"]; | |
| cacheId = (cacheId ? cacheId + "_" : "") + this.bounds.toBBOX(); | |
| form.action = OpenLayers.Util.urlAppend(this.layer.url, cacheId); | |
| // insert the iframe, which has been removed to avoid back-button | |
| // problems | |
| this.imgDiv.insertBefore(this.createIFrame(), this.imgDiv.firstChild); | |
| form.target = this.id+'_iFrame'; | |
| // adding all parameters in layer params as hidden fields to the html | |
| // form element | |
| var imageSize = this.layer.getImageSize(); | |
| var params = OpenLayers.Util.extend( | |
| { | |
| "BBOX": this.encodeBBOX ? this.bounds.toBBOX() : | |
| this.bounds.toArray(), | |
| "WIDTH": imageSize.w, | |
| "HEIGHT": imageSize.h | |
| }, this.layer.params); | |
| for(var par in params) { | |
| var field = document.createElement('input'); | |
| field.type = 'hidden'; | |
| field.name = par; | |
| field.value = params[par]; | |
| form.appendChild(field); | |
| } | |
| return form; | |
| }, | |
| CLASS_NAME: "OpenLayers.Tile.Image.IFrame" | |
| } | |
| ); | |