【原创】东方耀reactnative 视频18之-Touchable组件

rn有三个组件有被点击能力（去包裹其他组件）
1 TouchableHighlight 高亮
onHideUnderlay, onShowUnderlay,underlayColor(点击时背景阴影效果的背景色)
2 TouchableOpacity 设置透明度
activeOpacity

3 TouchableWithoutFeedback//不建议用

/**
* Sample React Native App
* https://github.com/facebook/react-native
* @flow
*/

import React, { Component } from ‘react’;
import {
AppRegistry,
StyleSheet,
TouchableHighlight,
TouchableOpacity,
TouchableWithoutFeedback,

PixelRatio,
Text,
TextInput,
View
} from ‘react-native’;

var onePT = 1/PixelRatio.get();

class demo2 extends Component {

render() {
return (