HarmonyOS 如何实现滑动监听？

@Entry  
@Component  
struct ScrollFontSizePage {  
  @State fontSize: number = 10  
  private msg: string = 'Scroll to Resize'  
  scroller: Scroller = new Scroller;  
  private arr: number[] = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15]  
  build() {  
    Column() {  
      Text(this.msg)  
        .fontSize(this.fontSize)  
        .fontWeight(FontWeight.Bold)  
      Scroll(this.scroller) {  
        Column() {  
          ForEach(this.arr, (item: number) => {  
            Text(item.toString())  
              .width('90%')  
              .height(200)  
              .backgroundColor(0xFFFFFF)  
              .borderWidth(1)  
              .borderColor(Color.Black)  
              .borderRadius(15)  
              .fontSize(16)  
              .textAlign(TextAlign.Center)  
          }, (item: string) => item)  
        }.width('100%').backgroundColor(0xDCDCDC)  
      }  
      .backgroundColor(Color.Yellow)  
      .height(600)  
      .edgeEffect(EdgeEffect.Spring)  
      .onScrollStop(() => {  
        let offset = this.scroller.currentOffset(); //返回当前的滚动偏移量  
        //xOffset:水平方向偏移量，yOffset：垂直方向偏移量  
        console.log(`scroll cur ${offset.xOffset}, ${offset.yOffset}`)  
        this.fontSize = 26 - (2600 - offset.yOffset) / 100  
      })  
  
      Row() {  
        Button('Top').fontSize(20).fontWeight(FontWeight.Bold).onClick(() => {  
          this.scroller.scrollTo({ xOffset: 0, yOffset: 0, animation: { duration: 1000, curve: Curve.Ease } })  
        }  
        )  
        Button('Mid').fontSize(20).fontWeight(FontWeight.Bold).onClick(() => {  
          this.scroller.scrollTo({ xOffset: 0, yOffset: 400, animation: { duration: 1000, curve: Curve.Ease } })  
        }  
        )  
        Button('Bottom').fontSize(20).fontWeight(FontWeight.Bold).onClick(() => {  
          this.scroller.scrollTo({ xOffset: 0, yOffset: 1800, animation: { duration: 1000, curve: Curve.Ease } })  
        }  
        )  
      }  
    }  
  }  
}
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.
49.
50.
51.
52.
53.
54.