Add improved navigation control support for disabling zooming with the

mousewheel. Original from sbenthall (yay), example and more code from me, tests
from elem. r=elemoine.  (Closes #1339)


git-svn-id: http://svn.openlayers.org/trunk/openlayers@6462 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Control/Navigation.js

@@ -36,6 +36,12 @@ OpenLayers.Control.Navigation = OpenLayers.Class(OpenLayers.Control, {
      */
     zoomBox: null,
 
+    /**
+     * APIProperty: zoomWheelEnabled
+     * {Boolean} Whether the mousewheel should zoom the map
+     */
+    zoomWheelEnabled: true, 
+
     /**
      * Constructor: OpenLayers.Control.Navigation
      * Create a new navigation control
@@ -75,7 +81,9 @@ OpenLayers.Control.Navigation = OpenLayers.Class(OpenLayers.Control, {
      */
     activate: function() {
         this.dragPan.activate();
-        this.handlers.wheel.activate();
+        if (this.zoomWheelEnabled) {
+            this.handlers.wheel.activate();
+        }    
         this.handlers.click.activate();
         this.zoomBox.activate();
         return OpenLayers.Control.prototype.activate.apply(this,arguments);
@@ -168,6 +176,26 @@ OpenLayers.Control.Navigation = OpenLayers.Class(OpenLayers.Control, {
     wheelDown: function(evt) {
         this.wheelChange(evt, -1);
     },
+    
+    /**
+     * Method: disableZoomWheel
+     */
+    
+    disableZoomWheel : function() {
+        this.zoomWheelEnabled = false;
+        this.handlers.wheel.deactivate();       
+    },
+    
+    /**
+     * Method: enableZoomWheel
+     */
+    
+    enableZoomWheel : function() {
+        this.zoomWheelEnabled = true;
+        if (this.active) {
+            this.handlers.wheel.activate();
+        }    
+    },
 
     CLASS_NAME: "OpenLayers.Control.Navigation"
 });