如何实现动画转场效果

页面A 
import router from '@ohos.router'; 
 
@Entry 
@Component 
struct Index { 
  @State message: string = 'Hello World'; 
 
  build() { 
    Row() { 
      Column() { 
        Button('点我吧') 
          .onClick(()=>{ 
            router.pushUrl({ 
              url:'pages/Page1' 
            }) 
          }) 
      } 
      .width('100%') 
    } 
    .height('100%') 
  } 
}
页面B 
@Entry 
@Component 
struct ComponentTransition { 
  @State flag: boolean = true; 
  @State value: AnimateParam = { 
    duration: 0, curve: Curve.Linear 
  } 
 
  pageTransition() { 
    PageTransitionExit({ type: RouteType.None, duration: 0 }) 
    PageTransitionEnter({ type: RouteType.None, duration: 0 }) 
  } 
 
  build() { 
    Stack({ alignContent: Alignment.Bottom }) { 
      if (this.flag) { 
        ComponentChild1({ flag: $flag, value: $value }) 
          .transition(TransitionEffect.move(TransitionEdge.END) 
            .animation(this.value)) 
      } 
      if (!this.flag) { 
        ComponentChild2({ flag: $flag }) 
          .transition(TransitionEffect.move(TransitionEdge.END) 
            .animation({ duration: 500, curve: Curve.Linear })) 
      } 
    }.height('100%').width('100%') 
  } 
} 
 
@Component 
struct ComponentChild1 { 
  @Link flag: boolean 
  @Link value: AnimateParam 
 
  build() { 
    Column() { 
      Text('aaa').fontSize('50') 
        .onTouch(() => { 
          this.value = { 
            duration: 1000, curve: Curve.Linear 
          } 
        }) 
        .onClick(() => { 
          animateTo({ duration: 1000 }, () => { 
            this.flag = !this.flag; 
          }) 
        }) 
    }.width('100%').height(('100%')).backgroundColor(Color.White) 
  } 
} 
 
@Component 
struct ComponentChild2 { 
  @Link flag: boolean 
 
  build() { 
    Column() { 
      Image($r('app.media.icon')) 
        .width('100%') 
        .height(200) 
        .onClick(() => { 
          animateTo({ duration: 1000 }, () => { 
            this.flag = !this.flag; 
          }) 
        }) 
    }.width('100%').height(('100%')).backgroundColor(Color.White) 
  } 
}