Taro: [taro-v3.0.0.beta.0]Taro.pxTransform中的taro.config拿不到值

Created on 19 Mar 2020 · 6Comments · Source: NervJS/taro

问题描述

复现步骤

在组件中使用的Taro

/**
 * 这段注释后可以贴代码
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 * 
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 */
// 这是taro核心代码
const pxTransform = function (size) {
  const { designWidth } = taro.config
  return Math.ceil((((parseInt(size, 10) / 40) * 640) / designWidth) * 10000) / 10000 + 'rem'
}

// 这是我用到的地方，源码：https://raw.githubusercontent.com/shenghanqin/quickly-mask/feature/next-react-20200213/taro/src/components/taro-cropper/index.tsx
const finishStyle: CSSProperties = {
        position: 'absolute',
        display: 'inline-block',
        color: themeColor,
        textAlign: "right",
        fontSize: Taro.pxTransform(32),
        bottom: Taro.pxTransform(30),
        right: Taro.pxTransform(30),
      };

期望行为

期望能正常使用这个转换

报错信息

Uncaught TypeError: Cannot read property 'designWidth' of undefined
    at Object.pxTransform (index.js?c00c:54)
    at TaroCropperComponent.render (index.tsx?8f0a:530)
    at finishClassComponent (react-dom.development.js?61bb:17176)
    at updateClassComponent (react-dom.development.js?61bb:17129)
    at beginWork (react-dom.development.js?61bb:18624)
    at HTMLUnknownElement.callCallback (react-dom.development.js?61bb:184)
    at Object.invokeGuardedCallbackDev (react-dom.development.js?61bb:236)
    at invokeGuardedCallback (react-dom.development.js?61bb:289)
    at beginWork$1 (react-dom.development.js?61bb:23234)
    at performUnitOfWork (react-dom.development.js?61bb:22178)