fix: 如果导览为空 则不做就近检测

scene/public/static/data/data.json

@@ -6,7 +6,7 @@
       {
         "name": "西雁翅楼",
         "label": "茶世界",
-        "num": "KJ-t-tHpdpKvb0ew",
+        "num": "KJ-CmveHNimLmQ",
         "content": {
           "title": "前言",
           "descs": [

scene/public/static/js/main_2020_show.js

@@ -5240,7 +5240,7 @@ window.Modernizr = function(n, e, t) {
             
             n.prototype.atEndOfTour = function(currentItem=this.currentItem) { 
                                                             
-                var end = currentItem && currentItem[0] >= this.nItems - 1; 
+                var end = this.model.heroLocations.length > 0 && currentItem && currentItem[0] >= this.nItems - 1; 
                 if(end){
                     var heroLocations = this.model.heroLocations[this.nItems-1].heroLocations
                     if(heroLocations){