var Dimensions = require('Dimensions');
在react-native -v0.61中这样调用Dimensions报错
image.png
undefined unable to resolve module就是未定义的模块，要改为以下的方式去调用
var react = require('react-native');
var {Dimensions} = react;
var {width, height} = Dimensions.get('window');
reactnative指定模拟器
react-native run-ios --simulator "iPhone 11 Pro”
