Files
openlayers/src/ol/featureloader.js
2015-04-27 09:56:01 +02:00

104 lines
3.5 KiB
JavaScript

goog.provide('ol.FeatureLoader');
goog.provide('ol.featureloader');
goog.require('goog.asserts');
goog.require('goog.events');
goog.require('goog.net.EventType');
goog.require('goog.net.XhrIo');
goog.require('goog.net.XhrIo.ResponseType');
goog.require('ol.format.FormatType');
goog.require('ol.xml');
/**
* @api
* @typedef {function(this:ol.source.Vector, ol.Extent, number,
* ol.proj.Projection)}
*/
ol.FeatureLoader;
/**
* @param {string} url Feature URL service.
* @param {ol.format.Feature} format Feature format.
* @param {function(this:ol.source.Vector, Array.<ol.Feature>)} success
* Function called with the loaded features. Called with the vector
* source as `this`.
* @return {ol.FeatureLoader} The feature loader.
*/
ol.featureloader.loadFeaturesXhr = function(url, format, success) {
return (
/**
* @param {ol.Extent} extent Extent.
* @param {number} resolution Resolution.
* @param {ol.proj.Projection} projection Projection.
* @this {ol.source.Vector}
*/
function(extent, resolution, projection) {
var xhrIo = new goog.net.XhrIo();
xhrIo.setResponseType(goog.net.XhrIo.ResponseType.TEXT);
goog.events.listen(xhrIo, goog.net.EventType.COMPLETE,
/**
* @param {Event} event Event.
* @private
* @this {ol.source.Vector}
*/
function(event) {
var xhrIo = event.target;
goog.asserts.assertInstanceof(xhrIo, goog.net.XhrIo,
'event.target/xhrIo is an instance of goog.net.XhrIo');
if (xhrIo.isSuccess()) {
var type = format.getType();
/** @type {Document|Node|Object|string|undefined} */
var source;
if (type == ol.format.FormatType.JSON) {
source = xhrIo.getResponseText();
} else if (type == ol.format.FormatType.TEXT) {
source = xhrIo.getResponseText();
} else if (type == ol.format.FormatType.XML) {
if (!goog.userAgent.IE) {
source = xhrIo.getResponseXml();
}
if (!goog.isDefAndNotNull(source)) {
source = ol.xml.parse(xhrIo.getResponseText());
}
} else {
goog.asserts.fail('unexpected format type');
}
if (goog.isDefAndNotNull(source)) {
var features = format.readFeatures(source,
{featureProjection: projection});
success.call(this, features);
} else {
goog.asserts.fail('undefined or null source');
}
} else {
// FIXME
}
goog.dispose(xhrIo);
}, false, this);
xhrIo.send(url);
});
};
/**
* Create an XHR feature loader for a `url` and `format`. The feature loader
* loads features (with XHR), parses the features, and adds them to the
* vector source.
* @param {string} url Feature URL service.
* @param {ol.format.Feature} format Feature format.
* @return {ol.FeatureLoader} The feature loader.
* @api
*/
ol.featureloader.xhr = function(url, format) {
return ol.featureloader.loadFeaturesXhr(url, format,
/**
* @param {Array.<ol.Feature>} features The loaded features.
* @this {ol.source.Vector}
*/
function(features) {
this.addFeatures(features);
});
};