Angular Material Autocomplete force selection

Question

In my angular 5 application I have some matAutocomplete, but I want to force the selection of oone of suggestions, so I am following this approach: stackblitz but for some reas

Answer 1

I found this helpful:

private subscribeToClosingActions(): void {
if (this.subscription && !this.subscription.closed) {
  this.subscription.unsubscribe();
}

this.subscription = this.autoCompleteTrigger.panelClosingActions
  .subscribe((e) => {
      if (!e || !e.source) {
        const selected = this.matAutocomplete.options
          .map(option => option.value)
          .find(option => option === this.formControl.value);

        if (selected == null) {
          this.formControl.setValue(null);
        }
      }
    },
    err => this.subscribeToClosingActions(),
    () => this.subscribeToClosingActions());
}