mp-uploader组件为啥不能显示?开发工具中预览是正常的

<view class="page">
    <view class="page__hd">
        <view class="page__title">Uploader</view>
        <view class="page__desc">上传组件</view>
    </view>
    <view class="page__bd">
        <mp-cells>
            <mp-cell>
                <mp-uploader bindfail="uploadError" bindsuccess="uploadSuccess" select="{{selectFile}}" upload="{{uplaodFile}}" files="{{files}}" max-count="5" title="图片上传" tips="图片上传提示"></mp-uploader>
            </mp-cell>
        </mp-cells>
    </view>
</view>
这段代码是从教程文档里面拷贝的,然而真机并不能用,安卓苹果都测试了