HarmonyOS 鸿蒙Next弹窗大小根据展示内容动态变化，但设置最大高度，超过该高度呈现滚动效果

可以在你的弹窗UI不设置高度，最外层包裹Scroll，设置最大高度.constraintSize({ maxHeight: 100 })，超过就会有滚动效果，参考demo

import { PromptAction } from '@kit.ArkUI';

@Entry
@Component
struct Index {
  promptAction: PromptAction = this.getUIContext().getPromptAction()
  private customDialogComponentId: number = 0
  scroller: Scroller = new Scroller()

  @Builder
  customDialogComponent() {
    Scroll(this.scroller) {
      Column {
        Text('弹窗').fontSize(30)
        Column().backgroundColor(Color.Red).width(50).height(150)
        Row({ space: 50 }) {
          Button("确认").onClick(() => {
            this.promptAction.closeCustomDialog(this.customDialogComponentId)
          })
          Button("取消").onClick(() => {
            this.promptAction.closeCustomDialog(this.customDialogComponentId)
          })
        }
      }
    }.scrollable(ScrollDirection.Vertical) // 滚动方向纵向
    .scrollBar(BarState.On) // 滚动条常驻显示
    .scrollBarColor(Color.Gray) // 滚动条颜色
    .scrollBarWidth(1) // 滚动条宽度
    .friction(0.6)
    .edgeEffect(EdgeEffect.None)
    .constraintSize({ maxHeight: 100 })
    .onScrollStop(() => {
      console.info('Scroll Stop')
    })
  }

  build() {
    Row() {
      Column() {
        Button("click me")
          .onClick(() => {
            this.promptAction.openCustomDialog({
              builder: () => {
                this.customDialogComponent()
              },
              onWillDismiss: (dismissDialogAction: DismissDialogAction) => {
                console.info("reason" + JSON.stringify(dismissDialogAction.reason))
                console.log("dialog onWillDismiss")
                if (dismissDialogAction.reason == DismissReason.PRESS_BACK) {
                  dismissDialogAction.dismiss()
                }
                if (dismissDialogAction.reason == DismissReason.TOUCH_OUTSIDE) {
                  dismissDialogAction.dismiss()
                }
              }
            }).then((dialogId: number) => {
              this.customDialogComponentId = dialogId
            })
          })
      }
      .width('100%')
      .height('100%')
    }
    .height('100%')
  }
}