/* 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/Format/Text.js
* @requires OpenLayers/Request/XMLHttpRequest.js
*/
/**
* Class: OpenLayers.Layer.Text
* This layer creates markers given data in a text file. The <location>
* property of the layer (specified as a property of the options argument
* in the <OpenLayers.Layer.Text> constructor) points to a tab delimited
* file with data used to create markers.
*
* The first row of the data file should be a header line with the column names
* of the data. Each column should be delimited by a tab space. The
* possible columns are:
* - *point* lat,lon of the point where a marker is to be placed
* - *lat* Latitude of the point where a marker is to be placed
* - *lon* Longitude of the point where a marker is to be placed
* - *icon* or *image* URL of marker icon to use.
* - *iconSize* Size of Icon to use.
* - *iconOffset* Where the top-left corner of the icon is to be placed
* relative to the latitude and longitude of the point.
* - *title* The text of the 'title' is placed inside an 'h2' marker
* inside a popup, which opens when the marker is clicked.
* - *description* The text of the 'description' is placed below the h2
* in the popup. this can be plain text or HTML.
*
* Example text file:
* (code)
* lat lon title description iconSize iconOffset icon
* 10 20 title description 21,25 -10,-25 http://www.openlayers.org/dev/img/marker.png
* (end)
*
* Inherits from:
* - <OpenLayers.Layer.Markers>
*/
OpenLayers.Layer.Text = OpenLayers.Class(OpenLayers.Layer.Markers, {
/**
* APIProperty: location
* {String} URL of text file. Must be specified in the "options" argument
* of the constructor. Can not be changed once passed in.
*/
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,
/**
* Constructor: OpenLayers.Layer.Text
* Create a text layer.
*
* Parameters:
* name - {String}
* options - {Object} Object with properties to be set on the layer.
* Must include <location> property.
*/
initialize: function(name, options) {
OpenLayers.Layer.Markers.prototype.initialize.apply(this, arguments);
this.features = new Array();
},
/**
* APIMethod: 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: loadText
* Start the load of the Text 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.
*/
loadText: function() {
if (!this.loaded) {
if (this.location != null) {
var onFail = function(e) {
this.events.triggerEvent("loadend");
};
this.events.triggerEvent("loadstart");
OpenLayers.Request.GET({
url: this.location,
success: this.parseData,
failure: onFail,
scope: this
});
this.loaded = true;
}
}
},
/**
* Method: moveTo
* If layer is visible and Text has not been loaded, load Text.
*
* 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.loadText();
}
},
/**
* Method: parseData
*
* Parameters:
* ajaxRequest - {<OpenLayers.Request.XMLHttpRequest>}
*/
parseData: function(ajaxRequest) {
var text = ajaxRequest.responseText;
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 parser = new OpenLayers.Format.Text(options);
var features = parser.read(text);
for (var i=0, len=features.length; i<len; i++) {
var data = {};
var feature = features[i];
var location;
var iconSize, iconOffset;
location = new OpenLayers.LonLat(feature.geometry.x,
feature.geometry.y);
if (feature.style.graphicWidth
&& feature.style.graphicHeight) {
iconSize = new OpenLayers.Size(
feature.style.graphicWidth,
feature.style.graphicHeight);
}
// FIXME: At the moment, we only use this if we have an
// externalGraphic, because icon has no setOffset API Method.
/**
* FIXME FIRST!!
* The Text format does all sorts of parseFloating
* The result of a parseFloat for a bogus string is NaN. That
* means the three possible values here are undefined, NaN, or a
* number. The previous check was an identity check for null. This
* means it was failing for all undefined or NaN. A slightly better
* check is for undefined. An even better check is to see if the
* value is a number (see #1441).
*/
if (feature.style.graphicXOffset !== undefined
&& feature.style.graphicYOffset !== undefined) {
iconOffset = new OpenLayers.Pixel(
feature.style.graphicXOffset,
feature.style.graphicYOffset);
}
if (feature.style.externalGraphic != null) {
data.icon = new OpenLayers.Icon(feature.style.externalGraphic,
iconSize,
iconOffset);
} else {
data.icon = OpenLayers.Marker.defaultIcon();
//allows for the case where the image url is not
// specified but the size is. use a default icon
// but change the size
if (iconSize != null) {
data.icon.setSize(iconSize);
}
}
if ((feature.attributes.title != null)
&& (feature.attributes.description != null)) {
data['popupContentHTML'] =
'<h2>'+feature.attributes.title+'</h2>' +
'<p>'+feature.attributes.description+'</p>';
}
data['overflow'] = feature.attributes.overflow || "auto";
var markerFeature = new OpenLayers.Feature(this, location, data);
this.features.push(markerFeature);
var marker = markerFeature.createMarker();
if ((feature.attributes.title != null)
&& (feature.attributes.description != null)) {
marker.events.register('click', markerFeature, this.markerClick);
}
this.addMarker(marker);
}
this.events.triggerEvent("loadend");
},
/**
* Property: 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) {
this.layer.map.addPopup(this.createPopup());
}
OpenLayers.Event.stop(evt);
},
/**
* Method: clearFeatures
*/
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.Text"
});