how-to-view-1.js

//...
constructor() {
  // You have to call the super() method to initialize the base class.
  super();
  this.controller.subscribe('counts', this.onCounts.bind(this));
}

// for more info: https://docs.redsift.com/docs/client-code-siftview
presentView(value) {
  console.log('counter: presentView: ', value);
  this.onCounts(value.data);
};

willPresentView(value) {
  console.log('counter: willPresentView: ', value);
};

onCounts(data) {
  console.log('counter: onCounts: ', data);
  document.getElementById('number').textContent = data.value;
}
// ...