/* 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/Control.js
*/
/**
* Class: OpenLayers.Control.ArgParser
* The ArgParser control adds location bar querystring parsing functionality
* to an OpenLayers Map.
* When added to a Map control, on a page load/refresh, the Map will
* automatically take the href string and parse it for lon, lat, zoom, and
* layers information.
*
* Inherits from:
* - <OpenLayers.Control>
*/
OpenLayers.Control.ArgParser = OpenLayers.Class(OpenLayers.Control, {
/**
* Parameter: center
* {<OpenLayers.LonLat>}
*/
center: null,
/**
* Parameter: zoom
* {int}
*/
zoom: null,
/**
* Parameter: layers
* {Array(<OpenLayers.Layer>)}
*/
layers: null,
/**
* APIProperty: displayProjection
* {<OpenLayers.Projection>} Requires proj4js support.
* Projection used when reading the coordinates from the URL. This will
*
* reproject the map coordinates from the URL into the map's
* projection.
*
* If you are using this functionality, be aware that any permalink
* which is added to the map will determine the coordinate type which
* is read from the URL, which means you should not add permalinks with
* different displayProjections to the same map.
*/
displayProjection: null,
/**
* Constructor: OpenLayers.Control.ArgParser
*
* Parameters:
* options - {Object}
*/
initialize: function(options) {
OpenLayers.Control.prototype.initialize.apply(this, arguments);
},
/**
* Method: setMap
* Set the map property for the control.
*
* Parameters:
* map - {<OpenLayers.Map>}
*/
setMap: function(map) {
OpenLayers.Control.prototype.setMap.apply(this, arguments);
//make sure we dont already have an arg parser attached
for(var i=0, len=this.map.controls.length; i<len; i++) {
var control = this.map.controls[i];
if ( (control != this) &&
(control.CLASS_NAME == "OpenLayers.Control.ArgParser") ) {
// If a second argparser is added to the map, then we
// override the displayProjection to be the one added to the
// map.
if (control.displayProjection != this.displayProjection) {
this.displayProjection = control.displayProjection;
}
break;
}
}
if (i == this.map.controls.length) {
var args = OpenLayers.Util.getParameters();
// Be careful to set layer first, to not trigger unnecessary layer loads
if (args.layers) {
this.layers = args.layers;
// when we add a new layer, set its visibility
this.map.events.register('addlayer', this,
this.configureLayers);
this.configureLayers();
}
if (args.lat && args.lon) {
this.center = new OpenLayers.LonLat(parseFloat(args.lon),
parseFloat(args.lat));
if (args.zoom) {
this.zoom = parseInt(args.zoom);
}
// when we add a new baselayer to see when we can set the center
this.map.events.register('changebaselayer', this,
this.setCenter);
this.setCenter();
}
}
},
/**
* Method: setCenter
* As soon as a baseLayer has been loaded, we center and zoom
* ...and remove the handler.
*/
setCenter: function() {
if (this.map.baseLayer) {
//dont need to listen for this one anymore
this.map.events.unregister('changebaselayer', this,
this.setCenter);
if (this.displayProjection) {
this.center.transform(this.displayProjection,
this.map.getProjectionObject());
}
this.map.setCenter(this.center, this.zoom);
}
},
/**
* Method: configureLayers
* As soon as all the layers are loaded, cycle through them and
* hide or show them.
*/
configureLayers: function() {
if (this.layers.length == this.map.layers.length) {
this.map.events.unregister('addlayer', this, this.configureLayers);
for(var i=0, len=this.layers.length; i<len; i++) {
var layer = this.map.layers[i];
var c = this.layers.charAt(i);
if (c == "B") {
this.map.setBaseLayer(layer);
} else if ( (c == "T") || (c == "F") ) {
layer.setVisibility(c == "T");
}
}
}
},
CLASS_NAME: "OpenLayers.Control.ArgParser"
});