Favorites list

HTML

<ul data-bind="foreach: favoriten">
  <li> <span data-bind="text: projectName, click: $parent.makeFavourite"></span>
    <img
    data-bind="visible: isFavourite" src="https://png.icons8.com/metro/1600/checkmark.png"
    width="16px" />
  </li>
</ul>

JavaScript

function Project(name, favorite) {
  var self = this;

  self.projectName = ko.observable(name);
  self.isFavourite = ko.observable(favorite);
}

function ViewModel() {
  var self = this;

  self.favoriten = ko.observableArray([
  new Project("Favorit1", false),
  new Project("Favorit2", true),
  new Project("Favorit3", false)]);

  self.makeFavourite = function (data, event) {
    data.isFavourite(!data.isFavourite());
  };
}

ko.applyBindings(new ViewModel());