如何给primeng自动完成占位符一个浮动标签函数？Angular 9+ PrimeNg

<input pAutoComplete [(ngModel)]="selectedValue" />

isFloatingLabel: boolean = false;

onInputFocus() {
  this.isFloatingLabel = true;
}

onInputBlur() {
  if (!this.selectedValue) {
    this.isFloatingLabel = false;
  }
}

<div class="input-wrapper" [ngClass]="{ 'float-label': isFloatingLabel }">
  <label *ngIf="isFloatingLabel">浮动标签</label>
  <input pAutoComplete [(ngModel)]="selectedValue" (focus)="onInputFocus()" (blur)="onInputBlur()" />
</div>

.float-label label {
  position: absolute;
  top: -20px;
  left: 10px;
  background-color: white;
  padding: 0 5px;
  font-size: 12px;
  color: gray;
}