====== サイズ取得 ======

===== 画面サイズ取得 =====

<code>
const Dimensions = require('Dimensions')
const { width, height, scale } = Dimensions.get('window')


[18:09:44] 411.42857142857144 //width
[18:09:44] 683.4285714285714 //height
[18:09:44] 2.625 //scale
</code>

===== ヘッダーやステータスバー =====
<code>
import { Header } from 'react-navigation'
import { StatusBar } from 'react-native'

・・・
console.log("Header.HEIGHT:" + Header.HEIGHT)
console.log("StatusBar .HEIGHT:" + StatusBar .HEIGHT)
</code>