MAPG-123 [WIP] use MutationObserver

public/static/js/game.js

@@ -336,23 +336,34 @@
         },
 
         rewriteGoogleLink: function () {
-            if (!Game.googleLink) {
-                var anchors = document.getElementById('panorama').getElementsByTagName('a');
-                for (var i = 0; i < anchors.length; i++) {
-                    var a = anchors[i];
-                    if (a.href.indexOf('maps.google.com/maps') !== -1) {
-                        Game.googleLink = a;
-                        break;
-                    }
+            if (Game.googleLink) {
+                return;
+            }
+
+            var anchors = document.getElementById('panorama').getElementsByTagName('a');
+            for (var i = 0; i < anchors.length; i++) {
+                var a = anchors[i];
+                if (a.href.indexOf('maps.google.com/maps') !== -1) {
+                    Game.googleLink = a;
+                    break;
                 }
             }
 
-            setTimeout(function () {
-                if (Game.googleLink) {
-                    Game.googleLink.title = 'Google Maps';
-                    Game.googleLink.href = 'https://maps.google.com/maps';
+            if (!Game.googleLink) {
+                return;
+            }
+
+            var observer = new MutationObserver(function(mutationsList, observer) {
+                for (let mutation of mutationsList) {
+                    if (mutation.attributeName === 'href' && Game.googleLink.href !== 'https://maps.google.com/maps') {
+                        console.log(Game.googleLink.href + ' is changed.')
+                        Game.googleLink.title = 'Google Maps';
+                        Game.googleLink.href = 'https://maps.google.com/maps';
+                    }
                 }
-            }, 1);
+            });
+
+            observer.observe(Game.googleLink, { attributes: true });
         }
     };
 
@@ -425,10 +436,6 @@
         Game.rewriteGoogleLink();
     });
 
-    Game.panorama.addListener('pov_changed', function () {
-        Game.rewriteGoogleLink();
-    });
-
     Game.initialize();
 
     document.getElementById('showGuessButton').onclick = function () {