add ajax code to WFS

git-svn-id: http://svn.openlayers.org/trunk/openlayers@174 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Tile/WFS.js

@@ -5,6 +5,13 @@ OpenLayers.Tile.WFS = Class.create();
 OpenLayers.Tile.WFS.prototype = 
   Object.extend( new OpenLayers.Tile(), {
 
+    /** @type Array of Function */
+    handlers: null,
+    
+    /** @type Array of */ 
+    features: null,
+
+
     /** 
     * @constructor
     *
@@ -14,12 +21,18 @@ OpenLayers.Tile.WFS.prototype =
     */
     initialize: function(bounds, url, size) {
         OpenLayers.Tile.prototype.initialize.apply(this, arguments);
+        
+        this.features = new Array();
+
+        this.handlers = new Array();
+        this.handlers["requestSuccess"] = this._requestSuccess;
     },
 
     /**
     */
     draw:function() {
         OpenLayers.Tile.prototype.draw.apply(this, arguments);
+        this.loadFeaturesForRegion("requestSuccess");        
     },
 
     /**
@@ -29,6 +42,73 @@ OpenLayers.Tile.WFS.prototype =
         this.position = pixel;
     },
     
+    /** get the full request string from the ds and the tile params 
+    *     and call the AJAX loadURL(). 
+    *
+    *     input are function pointers for what to do on success and failure.
+    * 
+    * @param {function} success
+    * @param {function} failure
+    */
+    loadFeaturesForRegion:function(success, failure) {
+
+        if (!this.loaded) {
+        
+            var server = this.ds.serverPath;
+            
+            if (server != "") {
+        
+                var queryString = this.getFullRequestString();
+                // TODO: Hmmm, this stops multiple loads of the data when a 
+                //       result isn't immediately retrieved, but it's hacky. 
+                //       Do it better.
+                this.loaded = true; 
+                ol.Log.info("request string: " + queryString);
+                ol.Application.loadURL(queryString, null, this, 
+                                       success, failure);
+            }
+        }
+    },
+    
+    /** Return from AJAX request
+    *
+    * @param {} request
+    */
+    requestSuccess:function(request) {
+    
+        var doc = request.responseXML;
+        
+        if (!doc || request.fileType!="XML") {
+            doc = ol.Application.parseXMLString(request.responseText);
+        }
+        
+        var resultFeatures = ol.Application.getNodes(doc, "gml:featureMember");
+        ol.Log.info(this.CLASS_NAME + " found " +
+                     resultFeatures.length + " features");
+            
+        //clear old featureList
+        this.features = new Array();
+
+        for (var i=0; i < resultFeatures.length; i++) {
+        
+            //create new Feature and add it 
+            var newFeature = new ol.Feature(resultFeatures[i]);
+
+            //add new marker
+            var newMarker = this._createMarker(newFeature);
+            this._addMarker(newMarker);
+
+            //save reference to the feature and marker
+            this.featureList[i] = new ol.Tile.WFS.FeatureItem(
+                                        newFeature, newMarker);
+    	}
+        
+        if (this.ds.markers != null) {
+            this.ds.markers.redraw();
+        }
+    },
+
+
     /** @final @type String */
     CLASS_NAME: "OpenLayers.Tile.WFS"
   }