replacing the select handler with a feature handler - with support for up, down, over, out, and move callbacks associated with mouse events on a feature - the select-feature.html example shows the use of a control that activates the feature handler - see #544

git-svn-id: http://svn.openlayers.org/trunk/openlayers@2843 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Handler/Feature.js

@@ -4,14 +4,15 @@
 
 
 /**
- * Handler to draw a path on the map.  Polygon is displayed on mouse down,
- * moves on mouse move, and is finished on mouse up.
+ * Handler to respond to mouse events related to a drawn feature.
+ * Callbacks will be called for over, move, out, up, and down (corresponding
+ * to the equivalent mouse events).
  * 
  * @class
  * @requires OpenLayers/Handler.js
  */
-OpenLayers.Handler.Select = OpenLayers.Class.create();
-OpenLayers.Handler.Select.prototype =
+OpenLayers.Handler.Feature = OpenLayers.Class.create();
+OpenLayers.Handler.Feature.prototype =
   OpenLayers.Class.inherit(OpenLayers.Handler, {
     
     /**
@@ -19,6 +20,11 @@ OpenLayers.Handler.Select.prototype =
      */
     layerIndex: null,
     
+    /**
+     * @type {OpenLayers.Geometry}
+     */
+    geometry: null,
+    
     /**
      * @constructor
      *
@@ -36,16 +42,19 @@ OpenLayers.Handler.Select.prototype =
     },
 
     /**
-     * Handle mouse down.  Call the "up" callback if down on a feature.
+     * Handle mouse down.  Call the "down" callback if down on a feature.
      * 
      * @param {Event} evt
      */
     mousedown: function(evt) {
-        return this.select('down', evt);
+        var selected = this.select('down', evt);
+        return !selected;  // stop event propagation if selected
     },
     
     /**
-     * Handle mouse moves.  Call the "over" callback if over a feature.
+     * Handle mouse moves.  Call the "move" callback if moving over a feature.
+     * Call the "over" callback if moving over a feature for the first time.
+     * Call the "out" callback if moving off of a feature.
      * 
      * @param {Event} evt
      */
@@ -55,37 +64,57 @@ OpenLayers.Handler.Select.prototype =
     },
 
     /**
-     * Handle mouse moves.  Call the "down" callback if up on a feature.
+     * Handle mouse moves.  Call the "up" callback if up on a feature.
      * 
      * @param {Event} evt
      */
     mouseup: function(evt) {
-        return this.select('up', evt);
+        var selected = this.select('up', evt);
+        return !selected;  // stop event propagation if selected        
     },
     
     /**
-     * Capture double-clicks.
+     * Capture double-clicks.  Let the event continue propagating if the 
+     * double-click doesn't hit a geometry.  Otherwise call the dblclick
+     * callback.
      *
+     * @param {Event} evt
      */
     dblclick: function(evt) {
-        return false;
+        var selected = this.select('dblclick', evt);
+        return !selected;  // stop event propagation if selected        
     },
 
     /**
      * Trigger the appropriate callback if a feature is under the mouse.
      *
      * @param {String} type Callback key
+     * @type {Boolean} A feature was selected
      */
     select: function(type, evt) {    
         var geometry = this.layer.renderer.getGeometryFromEvent(evt);
         if(geometry) {
-            if (geometry.parent) {
-                geometry = geometry.parent;
-            }    
+            // three cases:
+            // over a new, out of the last and over a new, or still on the last
+            if(!this.geometry) {
+                // over a new geometry
+                this.callback('over', [geometry]);
+            } else if(this.geometry != geometry) {
+                // out of the last and over a new
+                this.callback('out', [this.geometry]);
+                this.callback('over', [geometry]);
+            }
+            this.geometry = geometry;
             this.callback(type, [geometry]);
-            return false; // stop event propagation
+            return true;
+        } else {
+            if(this.geometry) {
+                // out of the last
+                this.callback('out', [this.geometry]);
+                this.geometry = null;
+            }
+            return false;
         }
-        return true;
     },
 
     /**
@@ -118,5 +147,5 @@ OpenLayers.Handler.Select.prototype =
     },
 
     /** @final @type String */
-    CLASS_NAME: "OpenLayers.Handler.Select"
+    CLASS_NAME: "OpenLayers.Handler.Feature"
 });