HarmonyOS 鸿蒙Next怎么在图片上添加二维码

HarmonyOS 鸿蒙Next怎么在图片上添加二维码 做分享，想在分享的图片上添加二维码。

做法： 在Canvas的context上drwaImage 先后把本地图片和二维码画上去。

1. 然后 context.getImageData 拿到图片数据。但是这个imageData 转成Uint8Array之后 添加到分享图片里面不生效。

2. 换一种尝试，把imageData 用buffer的方式存到沙盒路径。然后用uri的方式分享图片 出现的是一个占位图（也就是图片还是不生效）。

哪位大佬帮我解答一下是思路就错了吗？

附上我的代码：

export class Share {

  private static instance:Share
  private static imageData:ImageData

  constructor() {
  }

  static getInstance(){
    if (!Share.instance) {
      Share.instance = new Share()
    }
    return Share.instance
  }

  shareImage(){
    this.writeFile()
    Log.debug('begin share')
    let resultData = new Uint8Array(Share.imageData.data.buffer)
    let that = new util.types()
    let result = that.isUint8Array(resultData)
    Log.debug('看看是不是uint8Arr：'+result)
    const context = getContext(this) as common.UIAbilityContext
    //换成下面这个resultData就可以正常拉起分享
    // resultData = context.resourceManager.getMediaContentSync($r('app.media.sharetest')) as Uint8Array

    const contextFaker: Context = getContext(this);
    let filePath = contextFaker.filesDir + '/sharetest.jpg';

    let result2 = that.isUint8Array(resultData)
    Log.debug('2看看是不是uint8Arr：'+result2)

    Log.debug('filePath:'+filePath)
    Log.debug('查看沙箱路径:'+fileUri.getUriFromPath(filePath))
    let shareData: systemShare.SharedData = new systemShare.SharedData({
      utd: utd.UniformDataType.IMAGE,
      uri:fileUri.getUriFromPath(filePath),
      title: '图片标题', // 不传title字段时,显示图片文件名
      description: '图片描述' // 不传description字段时,显示图片大小
    });

    Log.debug('shareData:'+JSON.stringify(shareData))

    let controllerx: systemShare.ShareController = new systemShare.ShareController(shareData);
    let contextx = getContext(this) as common.UIAbilityContext;
    controllerx.show(contextx, {
      previewMode: systemShare.SharePreviewMode.DETAIL
    });
  }

  writeFile(){

    const context = getContext(this) as common.UIAbilityContext
    const fileDir = context.filesDir;
    [
      [context.resourceManager.getMediaContentSync($r('app.media.sharetest')),'/sharetest.jpg']
    ].forEach(item=>{
      let file = fs.openSync(fileDir + item[1], fs.OpenMode.READ_WRITE | fs.OpenMode.CREATE)

      let resultUint = new Uint8Array(Share.imageData.data.buffer)

      // let writeLen = fs.writeSync(file.fd,(item[0] as Uint8Array).buffer)
      let writeLen = fs.writeSync(file.fd,resultUint.buffer)

      Log.debug('write data to file Suc and size is:'+writeLen)
      fs.closeSync(file)
    })
  }

  async getImageData(context:CanvasRenderingContext2D){
    let imagePath = 'image/sharetest.jpg'
    let imageData = await this.generateShareImage(imagePath,context)
    Share.imageData = imageData
    Log.debug('image data 赋值成功')
  }

  async generateShareImage(imagePath:string,context:CanvasRenderingContext2D){
    let img:ImageBitmap = new ImageBitmap(imagePath)
    const settings: RenderingContextSettings = new RenderingContextSettings(true)
    Log.debug('开始生成二维码')
    const piexMap = await this.generateQRcode()
    Log.debug('生成二维码结束')
    context.drawImage(img,0,0,300,300)
    context.drawImage(piexMap,0,0,100,100)
    let imageData = context.getImageData(0,0,300,300)
    return imageData
  }

  generateQRcode():Promise<image.PixelMap> {
    return new Promise((resolve,reject)=>{
      let content: string = 'https://www.baidu.com';
      let options: generateBarcode.CreateOptions = {
        scanType: scanCore.ScanType.QR_CODE,
        height: 200,
        width: 200
      }
      let img:ImageBitmap = new ImageBitmap("image/testbg.png")
      try {
        // 码图生成接口，成功返回PixelMap格式图片
        generateBarcode.createBarcode(content, options).then((result: image.PixelMap) => {
          hilog.info(0x0001, 'hgh_logs', 'Promise createBarCode result: %{public}s', typeof result);
          resolve(result)
        }).catch((error: BusinessError) => {
          hilog.error(0x0001, 'hgh_logs', 'Promise Error: %{public}s', JSON.stringify(error));
          reject(error)
        })
      } catch (error) {
        hilog.error(0x0001, 'hgh_logs', 'Failed createBarCode Error: %{public}s', JSON.stringify(error));
        reject(error)
      }
    })
  }
}