fix

subpages/addMattresses/addMattresses.js

@@ -180,10 +180,12 @@ Page({
     });
 
     var oldDeviceList = wx.getStorageSync('deviceList');
-    self.setData({
-      deviceList: oldDeviceList,
-      showBluetoothList: true
-    });
+    if (oldDeviceList && oldDeviceList.length) {
+      self.setData({
+        deviceList: oldDeviceList,
+        showBluetoothList: true
+      });
+    }
     //第二步关闭适配器，重新来搜索
     wx.openBluetoothAdapter({
       success: function (res) {

subpages/addMattresses/addMattresses.wxml

@@ -10,9 +10,9 @@
 
     <view class="w-card">
         <van-field model:value="{{ placeOfUse }}" center title-width="150rpx" label="使用地点：" placeholder="可填写卧室等地点"
-            clearable border="{{ true }}" maxlength="10" />
+            clearable border="{{ true }}" maxlength="5" />
         <van-field model:value="{{ usingHuman }}" center title-width="150rpx" label="使用人：" placeholder="可填写本人或者其他人名称"
-            clearable border="{{ true }}" maxlength="8" />
+            clearable border="{{ true }}" maxlength="5" />
         <van-field model:value="{{ sn }}" center title-width="150rpx" clearable label="SN：" placeholder=""
             border="{{ true }}" readonly="{{ true }}" use-button-slot>
             <!-- <view slot="button" class="lysb-btn" bindtap="bindViewBlue">