How to detect web browser is loaded on inappbrowser

below is the code that I want to implement.
the problem is that when app is opened, I want to show loading icon and
when web browser is opened, want to dismiss it.
to do so, I should know when web browser is opened or not.

how can I detect that point?

export class HomePage {

  constructor(public inapp:InAppBrowser, public navCtrl: NavController) {

    const options : InAppBrowserOptions={
      zoom : 'no'
    }

    const browser = this.inapp.create("http://www.naver.com/" , '_self', options).on("message");
  }

}

InAppBrowser gets events by the browser inside. You should be able to handle those and dismiss any loading indicators.