【OpenHarmony】 鸿蒙视图缩放组件subsampling-scale-image-view

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简介

深度缩放视图,图像显示,手势平移缩放双击等

效果图(旋转、缩放、平移)

下载安装

ohpm install @ohos/subsampling-scale-image-view 

使用说明

生成SubsamplingScaleImageView

import {SubsamplingScaleImageView} from '@ohos/subsampling-scale-image-view';
...
//创建model对象
@State model: SubsamplingScaleImageView.Model  = new SubsamplingScaleImageView.Model()
...
build() {
  Stack({ alignContent: Alignment.Bottom }) {
   //使用SubsamplingScaleImageView组件
   SubsamplingScaleImageView({ model: this.model })
   Column({ space: 5 }) {
     Swiper(this.swiperController) {
       Row({ space: 5 }) {
         Text('This image is 7,800 x 6,240 pixels. On most devices it will be subsampled, and higher quality tiles are loaded as you zoom in.')
           .width('100%')
           .height(60)
           .layoutWeight(1)
           .fontColor(0xffffff)
           .textAlign(TextAlign.Center)
           .fontSize(16)
         Image($r('app.media.next'))
           .width(30)
           .height(30)
           .margin({ top: 6, left: 10 })
           .onClick((event: ClickEvent) => {
             this.index = 1;

           })
       }.width('100%').height(60).backgroundColor(0x3d3d3d)

       Row({ space: 5 }) {
         Image($r('app.media.previous')).width(30).height(30).margin({ top: 6 }).onClick((event: ClickEvent) => {
           this.index = 0;
         })
         Text('This image has been rotated 90 degrees. Tap the button to rotate it. EXIF rotation is supported for external files.')
           .width('100%')
           .height(60)
           .layoutWeight(1)
           .fontColor(0xffffff)
           .textAlign(TextAlign.Center)
           .fontSize(16)
         Image($r('app.media.rotate'))
           .width(30)
           .height(30)
           .margin({ top: 6, left: 10, right: 20 })
           .onClick((event: ClickEvent) => {
             this.mRotate += 90;
             this.model.setOrientation(this.mRotate)
           })
       }.width('100%').height(60).backgroundColor(0x3d3d3d)

     }
     .index(this.index)
     .autoPlay(false)
     .indicator(false) // 默认开启指示点
     .loop(false) // 默认开启循环播放
     .duration(50)
     .vertical(false) // 默认横向切换
     .itemSpace(0)
     .onChange((index: number) => {
       if (index == 1) {

         this.model.setImage($r('app.media.swissroad'));
       }
     })
   }.height(60).backgroundColor(0x3d3d3d).align(Alignment.Bottom)
 }
}
//设置图片源
aboutToAppear() {
 this.model.setImage($r('app.media.card'));
}
...

接口说明

  1. 设置图片资源
    public setImage(src: string | PixelMap | Resource)
    public setImage(src: string | PixelMap | Resource, previewSource: string | Resource)
    public setImage(src: string | PixelMap | Resource, state: ImageViewState)

2. 设置图片是否可缩放

    setZoomEnabled(zoomEnabled: boolean)

DD一下:欢迎大家关注工粽号<程序猿百晓生>,可以了解到以下知识点。

`欢迎大家关注工粽号<程序猿百晓生>,可以了解到以下知识点。`
1.OpenHarmony开发基础
2.OpenHarmony北向开发环境搭建
3.鸿蒙南向开发环境的搭建
4.鸿蒙生态应用开发白皮书V2.0 & V3.0
5.鸿蒙开发面试真题(含参考答案) 
6.TypeScript入门学习手册
7.OpenHarmony 经典面试题(含参考答案)
8.OpenHarmony设备开发入门【最新版】
9.沉浸式剖析OpenHarmony源代码
10.系统定制指南
11.【OpenHarmony】Uboot 驱动加载流程
12.OpenHarmony构建系统--GN与子系统、部件、模块详解
13.ohos开机init启动流程
14.鸿蒙版性能优化指南
.......
  1. 设置图片是否可平移
    public setPanEnabled(panEnabled: boolean)

4. 设置图片最大缩放比例

    public setMaxScale(maxScale: number)

5. 设置图片旋转角度

    public setOrientation(degrees: number)

6. 获取图片高宽

    public getSWidth()  
    public getSHeight()

7. 单击监听器

    public setSingleTapListener(listener: OnSingleTapListener)

8. 长按监听器

    public setLongPressListener(listener: OnLongPressListener)

9. 双击监听器

    public setDoubleTapListener(listener: OnDoubleTapListener)

约束与限制

在下述版本验证通过:

  • DevEco Studio: NEXT Beta1-5.0.3.806,SDK:API12 Release(5.0.0.66)
  • DevEco Studio NEXT Developer Beta3: 5.0(5.0.3.530)
  • SDK: API12 (5.0.0.35(SP3))

目录结构

|---- subsampling-scale-image-view 
    |---- entry # 示例代码文件夹      
    |---- library  
    |     |---- src
    |          |---- main
    |                |---- ets          
    |                      |---- components  # 库文件夹               
    |                           |---- SubsamplingScaleImageView.ets  # 自定义组件
    |                           |---- ImageViewState.ets  # 组件状态数据封装类  
    |     |---- index.ets  # 对外接口              
    |     |---- README_zh.md  # 安装使用方法