Update webloader.js

webloader.js

@@ -1,40 +1,42 @@
 /*
  * webloader.js
  */
-
 var FILE = require('lib/file');
 
-// https://stackoverflow.com/questions/597268/element-prototype-in-ie7
 if (!window.Element) {
     Element = function() {};
 
     var __createElement = document.createElement;
     document.createElement = function(tagName) {
         var element = __createElement(tagName);
-        for (var key in Element.prototype) {
-            element[key] = Element.prototype[key];
+        if (element == null) {
+            return null;
         }
+        for (var key in Element.prototype)
+            element[key] = Element.prototype[key];
         return element;
     }
 
     var __getElementById = document.getElementById;
     document.getElementById = function(id) {
         var element = __getElementById(id);
-        for (var key in Element.prototype) {
-            element[key] = Element.prototype[key];
+        if (element == null) {
+            return null;
         }
+        for (var key in Element.prototype)
+            element[key] = Element.prototype[key];
         return element;
     }
 }
 
-// https://gist.github.com/jonathantneal/3748027
 if (!window.addEventListener) {
     (function(WindowPrototype, DocumentPrototype, ElementPrototype, registry) {
         DocumentPrototype.head = (function() {
             return DocumentPrototype.getElementsByTagName("head")[0];
         })();
 
-		var addEventListener = function(type, listener) {
+        var inject = function(obj, registry) {
+            obj.addEventListener = function(type, listener) {
                 var target = this;
 
                 registry.unshift([target, type, listener, function(event) {
@@ -52,32 +54,26 @@ if (!window.addEventListener) {
 
                 this.attachEvent("on" + type, registry[0][3]);
             };
-        WindowPrototype.addEventListener = addEventListener;
-        DocumentPrototype.addEventListener = addEventListener;
-        ElementPrototype.ElementPrototype = addEventListener;
 
-        var removeEventListener = function(type, listener) {
+            obj.removeEventListener = function(type, listener) {
                 for (var index = 0, register; register = registry[index]; ++index) {
                     if (register[0] == this && register[1] == type && register[2] == listener) {
                         return this.detachEvent("on" + type, registry.splice(index, 1)[0][3]);
                     }
                 }
             };
-        WindowPrototype.removeEventListener = removeEventListener;
-        DocumentPrototype.removeEventListener = removeEventListener;
-        ElementPrototype.removeEventListener = removeEventListener;
 
-        var dispatchEvent = function(eventObject) {
+            obj.dispatchEvent = function(eventObject) {
                 return this.fireEvent("on" + eventObject.type, eventObject);
             };
-        WindowPrototype.dispatchEvent = dispatchEvent;
-        DocumentPrototype.dispatchEvent = dispatchEvent;
-        ElementPrototype.dispatchEvent = dispatchEvent;
+        };
+
+        inject(WindowPrototype, registry);
+        inject(DocumentPrototype, registry);
+        inject(ElementPrototype, registry);
     })(window, document, Element.prototype, []);
 }
 
-// https://stackoverflow.com/questions/10964966/detect-ie-version-prior-to-v9-in-javascript
-// https://stackoverflow.com/a/18249612
 var IEVersion = (function() {
     var undef,
         v = 3,
@@ -94,8 +90,6 @@ var IEVersion = (function() {
 
 return {
     setWindowDraggable: function() {
-        // https://stackoverflow.com/questions/21493777/how-to-make-a-tab-to-move-the-window-of-an-hta-application-in-vbscript
-        // https://stackoverflow.com/a/21497175
         var grip = document.getElementById('app'),
             oX, oY,
             mouseDown = function(e) {
@@ -117,20 +111,25 @@ return {
                 window.removeEventListener('mousemove', mouseMove);
                 window.removeEventListener('mouseup', mouseUp);
             };
+
         grip.addEventListener('mousedown', mouseDown);
         grip.addEventListener('mousemove', gripMouseMove);
     },
     getIEVersion: function() {
         return IEVersion;
     },
-    addScript: function(url, callback, test) {
-		var _callback = function(el) {
+    addScript: function(url, callback, test, ttl) {
+        var _callback = function(el, ttl) {
             setTimeout(function() {
                 var result = test(el);
                 if (typeof(result) !== "undefined") {
                     callback(el);
                 } else {
-					_callback(el);
+                    if (ttl > 0) {
+                        _callback(el, ttl - 50);
+                    } else {
+                        console.log("failed load " + url);
+                    }
                 }
             }, 50);
         };
@@ -142,37 +141,24 @@ return {
         document.head.appendChild(el);
 
         if (typeof(test) === "function") {
-			_callback();
+            // Time-To-Live: default value is 30 seconds
+            ttl = (typeof(ttl) == "number" ? ttl : 30000);
+            _callback(el, ttl);
         } else if (typeof(callback) === "function") {
             el.onload = callback(el);
         }
 
         return el;
     },
-    addStylesheet: function(url, callback, test) {
-		var _callback = function(el) {
-			setTimeout(function() {
-				var result = test(el);
-				if(typeof(result) !== "undefined") {
-					callback(el);
-				} else {
-					_callback(el);
-				}
-			}, 50);
-		};
-		
+    addStylesheet: function(url, callback) {
         var el = document.createElement("link");
         el.href = url;
         el.rel = "stylesheet";
         el.type = "text/css";
         document.head.appendChild(el);
-
-		if(typeof(test) === "function") {
-			_callback();
-		} else if(typeof(callback) === "function") {
+        if (typeof(callback) === "function") {
             el.onload = callback(el);
         }
-
         return el;
     },
     main: function() {