- 当前 Bug 的表现（可附上截图）

- 预期表现

- 复现路径

- 提供一个最简复现 Demo

<view class="page-body" style='position: fixed;overflow-y: scroll;width: 100%;height: 100%;'>

<view class="page-section">

<view class="page-section-title">输入区域高度自适应，不会出现滚动条</view>

<view class="textarea-wrp">

<textarea  fixed='true' value='输入区域高度自适应，不会出现滚动条' bindblur="bindTextAreaBlur" auto-height />

</view>

</view>

<view class="page-section">

<view class="page-section-title">这是一个可以自动聚焦的textarea</view>

<view class="textarea-wrp">

<textarea auto-focus="true" style="height: 3em" />

</view>

</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

<view>1111</view>

</view>

直接创建一个空白的小程序页面，然后在wxml文件中粘贴这段代码，手机预览就可看到效果