ReactNative 监听Android的物理返回事件！

import { Platform, BackHandler } from "react-native";

 componentWillMount() {
    if (Platform.OS === "android") {
      BackHandler.addEventListener("back", this.addListtenRequues);
    }
  }

  componentWillUnmount() {
    if (Platform.OS === "android") {
      BackHandler.removeEventListener("back");
    }
  }