HarmonyOS 自定义控件的aboutToAppear生命周期里执行animateTo动画没有效果

@Component  
export struct Block {  
  @Prop blockWidth: Length = 40  
  @Prop blockHeight: Length = 40  
  @Prop needDynamics: boolean = true  
  @Prop blockRadius: Resource | number = $r('app.float.radiusS')  
  @State opacityValue: number = this.needDynamics ? 0.4: 1  
  
  startAnimation () {  
    if (!this.needDynamics) return  
    animateTo({  
      playMode: PlayMode.Alternate,  
      iterations: -1,  
      duration: 1000,  
    }, () => {  
      this.opacityValue = 1  
    })  
  }  
  
  aboutToAppear(): void {  
    // 不加setTimeout动画无效，setTimeout感觉无法完全保证将动画执行放到build后  
    setTimeout(() => {  
      this.startAnimation()  
    }, 0)  
  }  
  
  build() {  
    Column()  
      .width(this.blockWidth)  
      .height(this.blockHeight)  
      .borderRadius(this.blockRadius)  
      .backgroundColor($r('app.color.fill2'))  
      .opacity(this.opacityValue)  
  }  
}