public void Views_created_from_an_observable_can_be_updated_by_the_observable() { var observable = new TestObservable(); var view = ContentView.FromObservable(observable); var isViewUpdated = false; view.Updated += (s, e) => { isViewUpdated = true; }; var initialSize = view.Measure(_renderer, new Size(10, 10)); initialSize.Height.Should().Be(0); initialSize.Width.Should().Be(0); observable.UpdateViews("Four"); isViewUpdated.Should().BeTrue(); var updatedSize = view.Measure(_renderer, new Size(10, 10)); updatedSize.Height.Should().Be(1); updatedSize.Width.Should().Be(4); }