The best part about components is that you can re-use them. This also applies to the timelines that you created for a component. When creating a transition component that contains another transition component you can add the subTimeline to your main timeline. There are three different ways of getting a child timeline

Method 1:

The first method is by using the components componentId to find it.

protected setupTransitionInTimeline(): void {
  this.transitionInTimeline.add(this.getSubTimeline('DummyComponent'));
}

Method 2:

The second method is by using the instance of the component to find it.

const component = <AbstractTransitionComponent>this.viewModel.$refs.dummyComponent;

protected setupTransitionInTimeline(): void {
  this.transitionInTimeline.add(this.getSubTimeline(component));
}

Method 3:

The third method is by using the components element

const component = <HTMLElement>this.viewModel.$el.querySelector('.dummy-component');

protected setupTransitionInTimeline(): void {
  this.transitionInTimeline.add(this.getSubTimeline(component));
}