ReactNative短信验证码倒计时控件的实现代码

import React, {Component } from 'react';
import {
  StyleSheet,
  Text,
  View,
  Image,
  TextInput,
  TouchableHighlight,
  StatusBar,
  Alert,
  AppRegistry
} from 'react-native';
import LinkRow from '../components/LinkRow';
import cStyles from '../styles/CommonStyle';

import axios from 'axios';

class MyCountTime extends Component {
  constructor(props) {
    super(props);
    let timeLeft = this.props.timeLeft > 0 ? this.props.timeLeft : 5;
    let width = this.props.width || 100;
    let height = this.props.height || 50;
    let color = this.props.color || '#42A5F5';
    let fontSize = this.props.fontSize || 30;
    let fontWeight = this.props.fontWeight || '600';
    let borderColor = this.props.borderColor || '#42A5F5';
    let borderWidth = this.props.borderWidth || 1;
    let borderRadius = this.props.borderRadius || 4;
    let backgroundColor = this.props.backgroundColor || '#42A5F5';
    let begin = 0;
    let press = this.props.press;

    this.afterEnd = this.props.afterEnd || this._afterEnd;
    this.style = this.props.style;

    this.state = {
      timeLeft: timeLeft,
      begin: begin
    };
    this.countTextStyle = {
      textAlign: 'center',
      color: '#42A5F5',
      fontSize: fontSize,
      fontWeight: fontWeight

    };
    this.countViewStyle = {
      backgroundColor: backgroundColor,
      alignItems: 'center',
      borderColor: borderColor,
      borderWidth: borderWidth,
      borderRadius: borderRadius,
      width: width,
      height: height
    }
  }

  countdownfn(timeLeft, callback, begin) {
    if (timeLeft > 0) {
      this.state.begin = 1;
      console.log("===lin===>");

      let that = this;
      let interval = setInterval(function () {
        if (that.state.timeLeft < 1) {
          clearInterval(interval);
          callback(that)
        } else {
          let totalTime = that.state.timeLeft;
          that.setState({
            timeLeft: totalTime - 1
          })
        }
      }, 1000)
    }
  }

  _beginCountDown() {
    if (this.state.begin === 1){
      return;
    }
    let time = this.state.timeLeft;
    console.log("===lin===> time " + time);
    let afterEnd = this.afterEnd;
    let begin = this.state.begin;
    console.log("===lin===> start " + begin);
    this.countdownfn(time, afterEnd, begin)
  }

  _afterEnd(that) {
    console.log('------------time over');
    that.setState({
      begin : 0,
      timeLeft : 5,
    })
  }

  componentDidMount() {

  }

  render() {
    return (
      
         { this.state.begin === 0 ? '点击获取验证码' : this.state.timeLeft} 

      
    )
  }
}