Extending Angular 2 dynamic forms to hide fields for certain values if conditions are met - forms

Question

I was following the example given on Dynamic Forms from the Angular 2 documentation (https://angular.io/docs/ts/latest/cookbook/dynamic-form.html). In this example you are shown how to create forms dynamically, based on metadata that describes the business object model.
This roughly looks as follows:
I have a YesNoQuestion class that describes how my questions are formatted.
import { QuestionBase } from './question-base';
export class YesNoQuestion extends QuestionBase<string> {
controlType = 'radio';
options: {key: string, value: string}[] = [];
constructor(options: {} = {}) {
super(options);
this.options = [
{key: 'true', value: 'Yes'},
{key: 'false', value: 'No'}
];
}
}
Each form is generated in my dynamic-form.component:
<div>
<form (ngSubmit)="onSubmit()" [formGroup]="form">
<div *ngFor="let question of questions" class="form-group">
<df-question [question]="question" [form]="form"></df-question>
</div>
<div class="form-row">
<button type="submit" [disabled]="!form.valid">Save</button>
</div>
</form>
<div *ngIf="payLoad" class="form-row">
<strong>Saved the following values</strong><br>{{payLoad}}
</div>
</div>
The dynamic-form calls the dynamic-form-question for each single question dynamic-form-question.component:
<div [formGroup]="form">
<label [attr.for]="question.key">{{question.label}}</label>
<div [ngSwitch]="question.controlType">
<div class="form-group" *ngSwitchCase="'radio'">
<div *ngFor="let opt of question.options">
<input type="radio" [formControlName]="question.key" [value]="opt.key" /> {{opt.value}}
</div>
</div>
... Some extra form types ...
</div>
<div class="errorMessage" *ngIf="!isValid">{{question.label}} is required</div>
</div>
Now I can generate a form by simply inserting a questions object like the following:
let questions: QuestionBase<any>[] = [
new YesNoQuestion({
key: 'a',
label: 'Label A',
}),
new YesNoQuestion({
key: 'b',
label: 'Label B',
}),
new YesNoQuestion({
key: 'c',
label: 'Label C',
}),
new TextareaQuestion({
key: 'd',
label: 'Label D',
}),
Now I am looking for a way to let these question be dependent of each other. I for example only want to see question A, and if yes is answered for question A I want to show question B. If no is answered I want to show question C.
Would something like that be implementable in my current approach? I haven't found a good tactic yet, I tried to add an attribute hide but didn't know how to reference other field values.