属性动画 (animation)或者显式动画 (animateTo)设置无限次播放之后如何进行关闭和动画切换？

@Entry  
@Component  
struct Page {  
  @State message: string = 'Hello World';  
  @State opacityValue: number = 1  
  build() {  
    Row() {  
      Column() {  
        Text(this.message)  
          .fontSize(50)  
          .fontWeight(FontWeight.Bold)  
          .opacity(this.opacityValue)  
        Button('开始动画').onClick(() => { animateTo({ duration: 5000, iterations: -1, playMode: PlayMode.AlternateReverse }, () => { this.opacityValue = 0 }) })  
        Button('结束动画').onClick(() => { animateTo({ duration: 0, iterations: 1, onFinish: () => { this.opacityValue = 1 } }, () => { this.opacityValue = 0.9 }) }) } .width('100%') } .height('100%') } }