Angular 2, Ionic. Can't resolve all parameter for HomePage

Question

What am I missing in the following? I'm trying to use cordova-camera-plugins and ionic native, with Ionic 2 but I receive the following Runtime Error after ionic serve: "Can't resolve all parameters for HomePage: ([object Object], [object Object], [object Object], [object Object], ?)."

Home.ts

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import { Component, Injectable } from '@angular/core';
import { NavController } from 'ionic-angular';
import { ToastController } from 'ionic-angular';
// import { File } from '@ionic-native/file';
import { Diagnostic } from '@ionic-native/diagnostic';
import { CameraPreview, CameraPreviewOptions, CameraPreviewDimensions} from '@ionic-native/camera-preview';
declare var cordova: any;

@Component({
  selector: 'page-home',
  templateUrl: 'home.html',

})

@Injectable()
export class HomePage {

  constructor(
    private navCtrl: NavController,
    private toastCtrl: ToastController,
    // public file:File,
    public diagnostic:Diagnostic,
    public cameraPreview: CameraPreview,
    public previewRect: CameraPreviewOptions
  ) {  this.checkPermissions(); }

app.module.ts

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import { NgModule, ErrorHandler } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { IonicApp, IonicModule, IonicErrorHandler } from 'ionic-angular';
import { MyApp } from './app.component';


import { HomePage } from '../pages/home/home';
import { Diagnostic } from '@ionic-native/diagnostic';


import { StatusBar } from '@ionic-native/status-bar';
import { SplashScreen } from '@ionic-native/splash-screen';

@NgModule({
  declarations: [
    MyApp,
    HomePage,
  ],
  imports: [
     BrowserModule,
     IonicModule.forRoot(MyApp)
  ],
  bootstrap: [IonicApp],
    entryComponents: [
     MyApp,
     HomePage,
     Diagnostic
  ],
  providers: [
    StatusBar,
    SplashScreen,
    Diagnostic,
    {provide: ErrorHandler, useClass: IonicErrorHandler},
    {provide: Diagnostic, useClass: Diagnostic}
   ]
})
export class AppModule {}

Answer 1

I used to get that same error and now it's fixed. "Can't resolve all parameters for HomePage: ([object Object], [object Object], [object Object], [object Object], ?).".

The "?" might mean not recognize or something, so try removing some parameters in the constructor and just declare them as normal data member( above the constructor). For example, "public previewRect: CameraPreviewOptions".