运行Android时，ionic v3相机预览插件错误

如何解决运行Android时，ionic v3相机预览插件错误

我想安装ionic v3相机预览插件https://ionicframework.com/docs/v3/native/camera-preview/，但没有成功，并向我显示错误， 我想在用户扫描QR码后自动拍照，这是我的代码：

app module.ts

import { CameraPreview,CameraPreviewPictureOptions,CameraPreviewOptions} from '@ionic-native/camera-preview';

providers: CameraPreview,scan.ts

import { CameraPreview,CameraPreviewOptions,CameraPreviewDimensions } from '@ionic-native/camera-preview';

here my function

  preview()

  {

    const cameraPreviewOpts: CameraPreviewOptions = {
      x: 0,y: 0,width: window.screen.width,height: window.screen.height,camera: 'rear',tapPhoto: true,previewDrag: true,toBack: true,alpha: 1
    };
    this.cameraPreview.startCamera(cameraPreviewOpts).then(
      (res) => {
        const pictureOpts: CameraPreviewPictureOptions = {
          width: 1280,height: 1280,quality: 85
        };
        this.cameraPreview.takePicture(pictureOpts).then((imageData) => {
          this.base64Image = 'data:image/jpeg;base64,' + imageData;
        },(err) => {
          console.log(err);
          // this.base64Image = 'assets/img/test.jpg';
        });
      },(err) => {
        console.log(err)
      });

  }

scan.html

ion-content style="background: none transparent"

    <img [src]="base64Image"/>


/ion-content

这里我得到错误：