bug fixes

learnOnline/pages/learnSystem/courseContent/publishDiscuss/publishDiscuss.wxml

 <!--pages/learnSystem/courseContent/publishDiscuss/publishDiscuss.wxml-->
-<view class='publish'>
+<main-page>
+  <view class='publish'>
   <view class='title'>
     <input type='text' placeholder='问题' bindinput="inputTitle" bindblur="inputTitle" value="{{publish.title}}"/>
   </view>
@@ -8,3 +9,4 @@
   </view>
   <view class='btn' bindtap='submitPublish'>发布问题</view>
 </view>
+</main-page>