/* 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"
});