* ng如果Firestore具有查询集合/ angularfire2

Question

I am working with Firestore and I need to filter my data by publicado and sort them by fechaCreacion . Then I tried this: this.afs.collection ('avisos', ref => ref.where ('publicado', '==', true) .orderBy ('fechaCreacion', 'desc')).valueChanges()

But it is not allowed by Firestore, according to the documentation. Then I was left alone with the order: this.afs.collection ('avisos', ref => ref.orderBy('fechaCreacion', 'desc')). valueChanges() this.afs.collection ('avisos', ref => ref.orderBy('fechaCreacion', 'desc')). valueChanges() and I'm trying to use *ngIf to show only those where publicado = true

<div *ngFor="let aviso of avisos | async as aviso" class="col-xl-2 col-lg-3 col-md-4 col-sm-6 col-6 my-1 px-1">
  <div *ngIf="aviso.publicado">
    <h6>{{ aviso.titulo }}</h6>
    <p>{{ aviso.descripcion }}</p>
  </div>
</div>

In part, I solve the problem but I have these gaps left. How can I solve that?

Answer 1

Filter your data inside of your typescript like this:

this.avisos = this.afs
    .collection('avisos', ref => ref.orderBy('fechaCreacion', 'desc'))
    .valueChanges()
    .map(data => data.filter(d => d.publicado));

Or filter via Firestore in your query (prefered way):

this.avisos = this.afs
    .collection('avisos', ref => ref
       .orderBy('fechaCreacion', 'desc'))
       .where('publicado', '==', true)
    .valueChanges();

It's important to order first, and then filter.