--- a/labs/openlayers/lib/OpenLayers/Layer/GeoRSS.js +++ b/labs/openlayers/lib/OpenLayers/Layer/GeoRSS.js @@ -1,1 +1,267 @@ - +/* 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/Layer/Markers.js + * @requires OpenLayers/Request/XMLHttpRequest.js + */ + +/** + * Class: OpenLayers.Layer.GeoRSS + * Add GeoRSS Point features to your map. + * + * Inherits from: + * - <OpenLayers.Layer.Markers> + * - <OpenLayers.Layer> + */ +OpenLayers.Layer.GeoRSS = OpenLayers.Class(OpenLayers.Layer.Markers, { + + /** + * Property: location + * {String} store url of text file + */ + location: null, + + /** + * Property: features + * {Array(<OpenLayers.Feature>)} + */ + features: null, + + /** + * APIProperty: formatOptions + * {Object} Hash of options which should be passed to the format when it is + * created. Must be passed in the constructor. + */ + formatOptions: null, + + /** + * Property: selectedFeature + * {<OpenLayers.Feature>} + */ + selectedFeature: null, + + /** + * APIProperty: icon + * {<OpenLayers.Icon>}. This determines the Icon to be used on the map + * for this GeoRSS layer. + */ + icon: null, + + /** + * APIProperty: popupSize + * {<OpenLayers.Size>} This determines the size of GeoRSS popups. If + * not provided, defaults to 250px by 120px. + */ + popupSize: null, + + /** + * APIProperty: useFeedTitle + * {Boolean} Set layer.name to the first <title> element in the feed. Default is true. + */ + useFeedTitle: true, + + /** + * Constructor: OpenLayers.Layer.GeoRSS + * Create a GeoRSS Layer. + * + * Parameters: + * name - {String} + * location - {String} + * options - {Object} + */ + initialize: function(name, location, options) { + OpenLayers.Layer.Markers.prototype.initialize.apply(this, [name, options]); + this.location = location; + this.features = []; + }, + + /** + * Method: destroy + */ + destroy: function() { + // Warning: Layer.Markers.destroy() must be called prior to calling + // clearFeatures() here, otherwise we leak memory. Indeed, if + // Layer.Markers.destroy() is called after clearFeatures(), it won't be + // able to remove the marker image elements from the layer's div since + // the markers will have been destroyed by clearFeatures(). + OpenLayers.Layer.Markers.prototype.destroy.apply(this, arguments); + this.clearFeatures(); + this.features = null; + }, + + /** + * Method: loadRSS + * Start the load of the RSS data. Don't do this when we first add the layer, + * since we may not be visible at any point, and it would therefore be a waste. + */ + loadRSS: function() { + if (!this.loaded) { + this.events.triggerEvent("loadstart"); + OpenLayers.Request.GET({ + url: this.location, + success: this.parseData, + scope: this + }); + this.loaded = true; + } + }, + + /** + * Method: moveTo + * If layer is visible and RSS has not been loaded, load RSS. + * + * Parameters: + * bounds - {Object} + * zoomChanged - {Object} + * minor - {Object} + */ + moveTo:function(bounds, zoomChanged, minor) { + OpenLayers.Layer.Markers.prototype.moveTo.apply(this, arguments); + if(this.visibility && !this.loaded){ + this.loadRSS(); + } + }, + + /** + * Method: parseData + * Parse the data returned from the Events call. + * + * Parameters: + * ajaxRequest - {<OpenLayers.Request.XMLHttpRequest>} + */ + parseData: function(ajaxRequest) { + var doc = ajaxRequest.responseXML; + if (!doc || !doc.documentElement) { + doc = OpenLayers.Format.XML.prototype.read(ajaxRequest.responseText); + } + + if (this.useFeedTitle) { + var name = null; + try { + name = doc.getElementsByTagNameNS('*', 'title')[0].firstChild.nodeValue; + } + catch (e) { + name = doc.getElementsByTagName('title')[0].firstChild.nodeValue; + } + if (name) { + this.setName(name); + } + } + + var options = {}; + + OpenLayers.Util.extend(options, this.formatOptions); + + if (this.map && !this.projection.equals(this.map.getProjectionObject())) { + options.externalProjection = this.projection; + options.internalProjection = this.map.getProjectionObject(); + } + + var format = new OpenLayers.Format.GeoRSS(options); + var features = format.read(doc); + + for (var i=0, len=features.length; i<len; i++) { + var data = {}; + var feature = features[i]; + + // we don't support features with no geometry in the GeoRSS + // layer at this time. + if (!feature.geometry) { + continue; + } + + var title = feature.attributes.title ? + feature.attributes.title : "Untitled"; + + var description = feature.attributes.description ? + feature.attributes.description : "No description."; + + var link = feature.attributes.link ? feature.attributes.link : ""; + + var location = feature.geometry.getBounds().getCenterLonLat(); + + + data.icon = this.icon == null ? + OpenLayers.Marker.defaultIcon() : + this.icon.clone(); + + data.popupSize = this.popupSize ? + this.popupSize.clone() : + new OpenLayers.Size(250, 120); + + if (title || description) { + // we have supplemental data, store them. + data.title = title; + data.description = description; + + var contentHTML = '<div class="olLayerGeoRSSClose">[x]</div>'; + contentHTML += '<div class="olLayerGeoRSSTitle">'; + if (link) { + contentHTML += '<a class="link" href="'+link+'" target="_blank">'; + } + contentHTML += title; + if (link) { + contentHTML += '</a>'; + } + contentHTML += '</div>'; + contentHTML += '<div style="" class="olLayerGeoRSSDescription">'; + contentHTML += description; + contentHTML += '</div>'; + data['popupContentHTML'] = contentHTML; + } + var feature = new OpenLayers.Feature(this, location, data); + this.features.push(feature); + var marker = feature.createMarker(); + marker.events.register('click', feature, this.markerClick); + this.addMarker(marker); + } + this.events.triggerEvent("loadend"); + }, + + /** + * Method: markerClick + * + * Parameters: + * evt - {Event} + */ + markerClick: function(evt) { + var sameMarkerClicked = (this == this.layer.selectedFeature); + this.layer.selectedFeature = (!sameMarkerClicked) ? this : null; + for(var i=0, len=this.layer.map.popups.length; i<len; i++) { + this.layer.map.removePopup(this.layer.map.popups[i]); + } + if (!sameMarkerClicked) { + var popup = this.createPopup(); + OpenLayers.Event.observe(popup.div, "click", + OpenLayers.Function.bind(function() { + for(var i=0, len=this.layer.map.popups.length; i<len; i++) { + this.layer.map.removePopup(this.layer.map.popups[i]); + } + }, this) + ); + this.layer.map.addPopup(popup); + } + OpenLayers.Event.stop(evt); + }, + + /** + * Method: clearFeatures + * Destroy all features in this layer. + */ + clearFeatures: function() { + if (this.features != null) { + while(this.features.length > 0) { + var feature = this.features[0]; + OpenLayers.Util.removeItem(this.features, feature); + feature.destroy(); + } + } + }, + + CLASS_NAME: "OpenLayers.Layer.GeoRSS" +}); +