鸿蒙 next 基于 @xwf/image_preview(V1.0.1) 开发自己的功能

import { CommonConstants } from '../constants/CommonConstants';import { ImagePreviewOption, ImageType } from '../model/ImagePreviewOption';import { MyImageItemView } from './MyImageItemView';
@Componentexport struct MyImagePreview {  //图片数据  option: ImagePreviewOption = { images: [], index: 0 }  //指示器样式  indicator: DotIndicator | DigitIndicator | boolean = new DotIndicator().color(Color.Gray).selectedColor(Color.Blue)  //页标改变监听  onChange: (index: number) => void = () => {  }  onSingleClickBg?: () => void  private DISPLAY_COUNT: number = 1  private MIN_SCALE: number = 0.75  @State private opacityList: number[] = []  @State private scaleList: number[] = []  @State private translateList: number[] = []  @State private zIndexList: number[] = []  @State private bgc: Color = Color.Black;
  aboutToAppear(): void {

    for (let i = 0; i < this.option.images.length; i++) {      this.opacityList.push(1.0)      this.scaleList.push(1.0)      this.translateList.push(0.0)      this.zIndexList.push(0)    }  }
  build() {    Stack() {      Swiper() {        ForEach(this.option.images, (image: ImageType, index: number) => {          MyImageItemView({ url: image, onSingleClickBg: this.onSingleClickBg })            .width(CommonConstants.THOUSANDTH_1000)            .height(CommonConstants.THOUSANDTH_1000)            .opacity(this.opacityList[index])            .scale({ x: this.scaleList[index], y: this.scaleList[index] })            .translate({ x: this.translateList[index] })            .zIndex(this.zIndexList[index])        })      }      .expandSafeArea([SafeAreaType.SYSTEM], [SafeAreaEdge.TOP, SafeAreaEdge.BOTTOM])      .width(CommonConstants.THOUSANDTH_1000)      .height(CommonConstants.THOUSANDTH_1000)      .loop(false)      .indicator(this.option.images.length > 1 ? this.indicator : false)      .displayCount(this.DISPLAY_COUNT, true)      .index(this.option.index)      .customContentTransition({        // 页面移除视窗时超时1000ms下渲染树        timeout: 1000,        // 对视窗内所有页面逐帧回调transition，在回调中修改opacity、scale、translate、zIndex等属性值，实现自定义动画        transition: (proxy: SwiperContentTransitionProxy) => {          if (proxy.position <= proxy.index % this.DISPLAY_COUNT ||            proxy.position >= this.DISPLAY_COUNT + proxy.index % this.DISPLAY_COUNT) {            // 同组页面往左滑或往右完全滑出视窗外时，重置属性值            this.opacityList[proxy.index] = 1.0            this.scaleList[proxy.index] = 1.0            this.translateList[proxy.index] = 0.0            this.zIndexList[proxy.index] = 0          } else {            // 同组页面往右滑且未滑出视窗外时，对同组中左右两个页面，逐帧根据position修改属性值，实现两个页面往Swiper中间靠拢并透明缩放的自定义切换动画            if (proxy.index % this.DISPLAY_COUNT === 0) {              this.opacityList[proxy.index] = 1 - proxy.position / this.DISPLAY_COUNT              this.scaleList[proxy.index] =                this.MIN_SCALE + (1 - this.MIN_SCALE) * (1 - proxy.position / this.DISPLAY_COUNT)              this.translateList[proxy.index] =                -proxy.position * proxy.mainAxisLength + (1 - this.scaleList[proxy.index]) * proxy.mainAxisLength / 2.0            } else {              this.opacityList[proxy.index] = 1 - (proxy.position - 1) / this.DISPLAY_COUNT              this.scaleList[proxy.index] =                this.MIN_SCALE + (1 - this.MIN_SCALE) * (1 - (proxy.position - 1) / this.DISPLAY_COUNT)              this.translateList[proxy.index] = -(proxy.position - 1) * proxy.mainAxisLength -                (1 - this.scaleList[proxy.index]) * proxy.mainAxisLength / 2.0            }            this.zIndexList[proxy.index] = -1          }        }      })      .onChange((index) => {        //this.option.index = index        this.onChange(index)      })
      // .onContentDidScroll((selectedIndex: number, index: number, position: number, mainAxisLength: number) => {      //   // 监听Swiper页面滑动事件，在该回调中可以实现自定义导航点切换动画等      //   //Logger.info("onContentDidScroll selectedIndex: " , selectedIndex + ", index: " + index + ", position: " + position + ", mainAxisLength: " + mainAxisLength)      // })    }    .expandSafeArea([SafeAreaType.SYSTEM], [SafeAreaEdge.TOP, SafeAreaEdge.BOTTOM])    .backgroundColor(this.bgc)    .width(CommonConstants.THOUSANDTH_1000)    .height(CommonConstants.THOUSANDTH_1000)  }}