diabook-theme: add "population density 2010"-layer to EarthLayers-box

view/theme/diabook/js/jquery.mapquery.legend.js

@@ -0,0 +1,87 @@
+/* Copyright (c) 2011 by MapQuery Contributors (see AUTHORS for
+ * full list of contributors). Published under the MIT license.
+ * See https://github.com/mapquery/mapquery/blob/master/LICENSE for the
+ * full text of the license. */
+
+/**
+#jquery.mapquery.legend.js
+A plugin on mapquery.core to add a legend to a layer. It will check if the layer
+is within a valid extent and zoom range. And if not will return an error message.
+*/
+
+(function($, MQ) {
+$.extend( $.fn.mapQuery.defaults.layer.all, {
+    legend: {
+        url: '',
+        msg: ''
+        }
+});
+//possible error messages to display in the legend
+LEGEND_ERRORS= ['E_ZOOMOUT', 'E_ZOOMIN', 'E_OUTSIDEBOX'];
+$.extend(MQ.Layer.prototype, {
+/**
+###**layer**.`legend([options])`
+_version added 0.1_
+####**Description**: get/set the legend of a layer
+
+**options** url:url the url to the legend image
+
+>Returns: {url:url, msg:'E\_ZOOMOUT' | 'E\_ZOOMIN' | 'E\_OUTSIDEBOX' | ''}
+
+
+The `.legend()` function allows us to attach a legend image to a layer. It will
+also check if the layer is not visible due to wrong extent or zoom level.
+It will return an error message which can be used to notify the user.
+
+
+     var legend = layer.legend();  //get the current legend
+     //set the legend url to legendimage.png
+     layer.legend({url:'legendimage.png'})
+
+ */
+    //get/set the legend object
+    legend: function(options) {
+        //get the legend object
+        var center = this.map.center();
+        if (arguments.length===0) {
+            this._checkZoom(center);
+            //if zoom = ok, check box
+            if(this.options.legend.msg==''){
+                this._checkBox(center);
+            }
+            return this.options.legend;
+        }
+        //set the legend url
+        if (options.url!==undefined) {
+            this.options.legend.url = options.url;
+            return this.options.legend;
+        }
+    },
+    //Check if the layer has a maximum box set and if the current box
+    //is outside these settings, set the legend.msg accordingly
+    _checkBox: function(center){
+        var maxExtent = this.options.maxExtent;
+        if(maxExtent!==undefined) {
+            var mapBounds = new OpenLayers.Bounds(
+        center.box[0],center.box[1],center.box[2],center.box[3]);
+            var layerBounds = new OpenLayers.Bounds(
+        maxExtent[0],maxExtent[1],maxExtent[2],maxExtent[3]);
+            var inside = layerBounds.containsBounds(mapBounds, true);
+            this.options.legend.msg = inside?'':LEGEND_ERRORS[2];
+        }
+    },
+    //Check if the layer has a minimum or maximum zoom set and if the
+    //current zoom is outside these settings, set the legend.msg accordingly
+    _checkZoom: function(center){
+        var zoom = center.zoom;
+        var maxZoom = this.options.maxZoom;
+        var minZoom = this.options.minZoom;
+        this.options.legend.msg=(
+        maxZoom!==undefined&&maxZoom<zoom)? LEGEND_ERRORS[0]:'';
+        this.options.legend.msg=(
+        minZoom!==undefined&&minZoom>zoom)? LEGEND_ERRORS[1]:'';
+    }
+
+});
+
+})(jQuery, $.MapQuery);