select-field-line.component.html

<div class="row">
    <!-- titre -->
    <div class="col-12 col-sm-3">
        {{_select.label}}
    </div>

    <!-- liste déroulante -->
    <div class="btn-group col-12 col-sm-9" dropdown (click)="onSelect($event)">
        <button dropdownToggle class="btn btn-primary dropdown-toggle waves-light my-1" type="button" mdbRippleRadius>
            {{currentLabel}}
        </button>
        <div class="dropdown-menu">
            <a class="dropdown-item" *ngFor="let e of entries" [value]=e>{{entryLabel(e)}}</a>
        </div>
    </div>
</div>