platform-ready.ts

const noop = () => { };
const DEVICEREADYEVENT = window['cordova'] ? "deviceready" : "DOMContentLoaded"
export function platformReady() {
  return function decorator(proto, method, descriptor) {
    const {
      ngOnInit = noop,
      ngOnDestroy = noop
    } = proto;
    const symbolHandler = Symbol(method);
    function addListener() {
      const handler = this[symbolHandler] = (...args) => {
        descriptor.value.apply(this, args);
      };
      document.addEventListener(DEVICEREADYEVENT, handler);
    }
    function removeListener() {
      document.addEventListener(DEVICEREADYEVENT, this[symbolHandler]);
    }
    proto.ngOnInit = function onInitWrapper() {
      ngOnInit.call(this);
      addListener.call(this);
    };
    proto.ngOnDestroy = function onDestroyWrapper() {
      ngOnDestroy.call(this)
      removeListener.call(this);
    }
  }
}