Merge pull request #179 from lukemurray/destroy

Add a destroy function on the viewer to clean up and remove elements

src/eventhandler.js

@@ -91,15 +91,21 @@ $.EventHandler.prototype = {
 
 
     /**
-     * Remove all event handler for a given event type.
+     * Remove all event handlers for a given event type. If no type is given all
+     * event handlers for every event type are removed.
      * @function
      * @param {String} eventName - Name of event for which all handlers are to be removed.
      */
-    removeAllHandlers: function( eventName ){
-        this.events[ eventName ] = [];
+    removeAllHandlers: function( eventName ) {
+        if (eventName){
+            this.events[ eventName ] = [];
+        } else{
+            for (var eventType in this.events) {
+                this.events[eventType] = [];
+            }
+        }
     },
 
-
     /**
      * Retrive the list of all handlers registered for a given event.
      * @function

src/mousetracker.js

@@ -171,6 +171,15 @@
 
     $.MouseTracker.prototype = {
 
+        /**
+         * Clean up any events or objects created by the mouse tracker.
+         * @function
+         */
+        destroy: function() {
+            stopTracking( this );
+            this.element = null;
+        },
+
         /**
          * Are we currently tracking events on this element.
          * @deprecated Just use this.tracking

src/overlay.js

@@ -157,6 +157,9 @@
                 }
             }
 
+            // clear the onDraw callback
+            this.onDraw = null;
+
             style.top = "";
             style.left = "";
             style.position = "";

src/viewer.js

@@ -499,7 +499,9 @@ $.extend( $.Viewer.prototype, $.EventHandler.prototype, $.ControlDock.prototype,
 
         this.viewport   = this.preserveViewport ? this.viewport : null;
         //this.profiler   = null;
-        this.canvas.innerHTML = "";
+        if (this.canvas){
+            this.canvas.innerHTML = "";
+        }
 
         VIEWERS[ this.hash ] = null;
         delete VIEWERS[ this.hash ];
@@ -509,6 +511,47 @@ $.extend( $.Viewer.prototype, $.EventHandler.prototype, $.ControlDock.prototype,
         return this;
     },
 
+    
+    /**
+     * Function to destroy the viewer and clean up everything created by
+     * OpenSeadragon.
+     * @function
+     * @name OpenSeadragon.Viewer.prototype.destroy
+     */
+    destroy: function( ) {
+        this.close();
+
+        this.removeAllHandlers();
+
+        // Go through top element (passed to us) and remove all children
+        // Use removeChild to make sure it handles SVG or any non-html
+        // also it performs better - http://jsperf.com/innerhtml-vs-removechild/15
+        if (this.element){
+            while (this.element.firstChild) {
+                this.element.removeChild(this.element.firstChild);
+            }
+        }
+
+        // destroy the mouse trackers
+        if (this.keyboardCommandArea){
+            this.keyboardCommandArea.innerTracker.destroy();
+        }
+        if (this.innerTracker){
+            this.innerTracker.destroy();
+        }
+        if (this.outerTracker){
+            this.outerTracker.destroy();
+        }
+
+        // clear all our references to dom objects
+        this.canvas = null;
+        this.keyboardCommandArea = null;
+        this.container = null;
+
+        // clear our reference to the main element - they will need to pass it in again, creating a new viewer
+        this.element = null;
+    },
+
 
     /**
      * @function

test/basic.js

@@ -208,4 +208,31 @@
         viewer.open('/test/data/testpattern.dzi');
     });
 
+    // ----------
+    asyncTest('Destroy', function() {
+        viewer.addHandler("open", function () {
+            // Check that the DOM has been modified
+            notEqual(0, $('#example').children().length);
+
+            var closeCalled = false;
+            var closeHandler = function() {
+                viewer.removeHandler('close', closeHandler);
+                closeCalled = true;
+            };
+
+            viewer.addHandler('close', closeHandler);
+            viewer.destroy();
+
+            // Check that the DOM has been cleaned up
+            equal(0, $('#example').children().length);
+            equal(null, viewer.canvas);
+            equal(null, viewer.keyboardCommandArea);
+            equal(null, viewer.container);
+            equal(null, viewer.element);
+            equal(true, closeCalled);
+            start();
+        });
+        viewer.open('/test/data/testpattern.dzi');
+    });
+
 })();