main.ts

const Contact = {
  props: ["id"],
  template: "<div>Contact view</div>",
  mounted: function() {
    console.log("Welcome to the Contact view");
    const userId = this.id;

    if (userId) {
      console.log("You are viewing the user", userId);
    }
  },
  destroyed: function() {
    console.log("Thanks for visiting to the Contact view");
  }
};