1、搭配view

<view wx:if="{{boolean==true}}">
<view class="bg_black"></view>
</view>
<view wx:elif="{{boolean==false}}">
<view class="bg_red"></view>
</view>
<view wx:elif>
<view class="bg_red"></view>
</view>

2、搭配block

<block  wx:if="{{order.kind===3}}">
<view class="bg_black"></view>
</block>
<block wx:else>
<view class="bg_red"></view>
</block>
<block wx:if="{{boolean==true}}">
<view class="bg_black"></view>
</block>
<block wx:elif="{{boolean==false}}">
<view class="bg_red"></view>
</block>
<block wx:else>
<view class="bg_red"></view>
</block>