asset-selector.html

<mat-form-field>
    <mat-label>
        Select Asset
    </mat-label>

    <mat-select (selectionChange)="assetSelected.next($event.value)">
        <mat-option *ngFor="let asset of (assets$ | async)" [value]="asset.id">
            {{ asset.name }}
        </mat-option>
    </mat-select>
</mat-form-field>