Ionic2 Error: “No provider for Storage”

问题:

After reading everything I could find, and failing, I must ask here:

I am trying to use ionic2's Storage, just like the doc tells me to,

doc: https://ionicframework.com/docs/storage/

here is my Code:

app-module.ts

    import { BrowserModule } from '@angular/platform-browser';
    import { ErrorHandler, NgModule } from '@angular/core';
    import { IonicApp, IonicErrorHandler, IonicModule } from 'ionic-angular';
    import { SplashScreen } from '@ionic-native/splash-screen';
    import { StatusBar } from '@ionic-native/status-bar';

    import { MyApp } from './app.component';
    import { HomePage } from '../pages/home/home';
    import { Intro } from '../pages/intro/intro';
    import { Checklist } from '../pages/checklist/checklist';
    // import { Http } from '@angular/http';
    import {IonicStorageModule} from '@ionic/Storage';
    import { Data } from '../providers/data';
    import {HttpModule} from '@angular/http';
    // import {Storage} from '@ionic/storage';


    @NgModule({
      declarations: [
        MyApp,
        HomePage,
        Intro,
        Checklist
      ],
      imports: [
        HttpModule,
        BrowserModule,
        IonicModule.forRoot(MyApp),
        IonicStorageModule.forRoot()
      ],
      bootstrap: [IonicApp],
      entryComponents: [
        MyApp,
        HomePage,
        Intro,
        Checklist
      ],
      providers: [
        StatusBar,
        SplashScreen,
        {provide: ErrorHandler, useClass: IonicErrorHandler},
        // Storage,
        //Http,
        Data
      ],
    })
    export class AppModule {}


data.ts

import { Injectable } from '@angular/core';
// import { Http } from '@angular/http';
import 'rxjs/add/operator/map';
// import { HttpModule } from '@angular/http';

import { Storage } from '@ionic/storage';


@Injectable()
export class Data {
  constructor(public storage: Storage) {
  }
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  getData(): Promise<any> {
    return this.storage.get('checklists');
  }
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  save(data): void {
    let saveData = [];
    //Remove observables
    data.forEach((checklist) => {
      saveData.push({
        title: checklist.title,
        items: checklist.items
      });
    });
    let newData = JSON.stringify(saveData);
    this.storage.set('checklists', newData);
  }
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
}

home.ts

// import { Component } from '@angular/core';
// import { NavController } from 'ionic-angular';

// @Component({
//   selector: 'page-home',
//   templateUrl: 'home.html'
// })
// export class HomePage {

//   constructor(public navCtrl: NavController) {

//   }

// }


import { Component } from '@angular/core';
import { NavController, AlertController, Platform } from 'ionic-angular';
import { Checklist } from '../checklist/checklist';
import { ChecklistModel } from '../../models/checklist-model';
import { Data } from '../../providers/data';
import { Keyboard } from 'ionic-native';
@Component({
  selector: 'page-home',
  templateUrl: 'home.html',
})
export class HomePage {
  checklists: ChecklistModel[] = [];

  constructor(public navCtrl: NavController, public dataService: Data,
    public alertCtrl: AlertController, public platform: Platform) {
  }

  // constructor(public navCtrl: NavController, public alertCtrl: AlertController, public platform: Platform) {
  //   // this.checklists.push(new ChecklistModel("Noam", [1,2,3]));
  // }
  ///////////////////////////////////////////////////////////////////////////////////////////////////////////
  ionViewDidLoad() {
  }
  ///////////////////////////////////////////////////////////////////////////////////////////////////////////
  addChecklist(): void {
    let prompt = this.alertCtrl.create({
      title: 'New Checklist',
      message: 'Enter the name of your new checklist below:',
      inputs: [
        {
          name: 'name'
        }
      ],
      buttons: [
        {
          text: 'Cancel'
        },
        {
          text: 'Save',
          handler: data => {
            let newChecklist = new ChecklistModel(data.name, []);
            this.checklists.push(newChecklist);
            newChecklist.checklistUpdates().subscribe(update => {
              this.save();
            });
            this.save();
          }
        }
      ]
    });
    prompt.present();
  }
  ///////////////////////////////////////////////////////////////////////////////////////////////////////////
  renameChecklist(checklist): void {
    let prompt = this.alertCtrl.create({
      title: 'Rename Checklist',

      message: 'Enter the new name of this checklist below:',
      inputs: [
        {
          name: 'name'
        }
      ],
      buttons: [
        {
          text: 'Cancel'
        },
        {
          text: 'Save',
          handler: data => {
            let index = this.checklists.indexOf(checklist);
            if (index > -1) {
              this.checklists[index].setTitle(data.name);
              this.save();
            }
          }
        }
      ]
    });
    prompt.present();
  }
  ///////////////////////////////////////////////////////////////////////////////////////////////////////////
  viewChecklist(checklist): void {
    this.navCtrl.push(Checklist, {
      checklist: checklist
    });
  }
  ///////////////////////////////////////////////////////////////////////////////////////////////////////////
  removeChecklist(checklist): void {
    let index = this.checklists.indexOf(checklist);
    if (index > -1) {
      this.checklists.splice(index, 1);
      this.save();
    }
  }
  ///////////////////////////////////////////////////////////////////////////////////////////////////////////
  save(): void {
    Keyboard.close();
    this.dataService.save(this.checklists);
  }
  ///////////////////////////////////////////////////////////////////////////////////////////////////////////
}

The method that is supposed to get called and use the Storage is HomePage's save().

I can't get that far, however, because before the page even loads, I get

Runtime Error Uncaught (in promise): Error: No provider for Storage! Error at g (http://localhost:8100/build/polyfills.js:3:7133) at injectionError (http://localhost:8100/build/main.js:1585:86) at noProviderError (http://localhost:8100/build/main.js:1623:12) at ReflectiveInjector_.throwOrNull (http://localhost:8100/build/main.js:3125:19) at ReflectiveInjector.getByKeyDefault (http://localhost:8100/build/main.js:3164:25) at ReflectiveInjector.getByKey (http://localhost:8100/build/main.js:3096:25) at ReflectiveInjector.get (http://localhost:8100/build/main.js:2965:21) at AppModuleInjector.get (ng:///AppModule/module.ngfactory.js:254:82) at AppModuleInjector.getInternal (ng:///AppModule/module.ngfactory.js:481:44) at AppModuleInjector.NgModuleInjector.get (http://localhost:8100/build/main.js:3929:44) at resolveDep (http://localhost:8100/build/main.js:11334:45) at createClass (http://localhost:8100/build/main.js:11202:32) at createDirectiveInstance (http://localhost:8100/build/main.js:11028:37) at createViewNodes (http://localhost:8100/build/main.js:12377:49) at createRootView (http://localhost:8100/build/main.js:12282:5)

Package.json:

{
  "name": "ionic-hello-world",
  "author": "Ionic Framework",
  "homepage": "http://ionicframework.com/",
  "private": true,
  "config": {
    "ionic_source_map": "source-map"
  },
  "scripts": {
    "clean": "ionic-app-scripts clean",
    "build": "ionic-app-scripts build",
    "ionic:build": "ionic-app-scripts build",
    "ionic:serve": "ionic-app-scripts serve"
  },
  "dependencies": {
    "@angular/common": "4.0.0",
    "@angular/compiler": "4.0.0",
    "@angular/compiler-cli": "4.0.0",
    "@angular/core": "4.0.0",
    "@angular/forms": "4.0.0",
    "@angular/http": "4.0.0",
    "@angular/platform-browser": "4.0.0",
    "@angular/platform-browser-dynamic": "4.0.0",
    "@ionic-native/core": "3.4.2",
    "@ionic-native/splash-screen": "3.4.2",
    "@ionic-native/status-bar": "3.4.2",
    "@ionic/storage": "^2.0.1",
    "ionic-angular": "3.0.1",
    "ionic-native": "^2.9.0",
    "ionicons": "3.0.0",
    "rxjs": "5.1.1",
    "sw-toolbox": "3.4.0",
    "zone.js": "^0.8.4"
  },
  "devDependencies": {
    "@ionic/app-scripts": "1.3.0",
    "typescript": "~2.2.1",
    "webpack": "^2.4.1"
  },
  "cordovaPlugins": [
    "cordova-plugin-whitelist",
    "cordova-plugin-console",
    "cordova-plugin-statusbar",
    "cordova-plugin-device",
    "cordova-plugin-splashscreen",
    "ionic-plugin-keyboard"
  ],
  "cordovaPlatforms": [],
  "description": "quicklists: An Ionic project"
}

Since I did everything the doc said, please enlighten me - What is still missing that would cause the Storage not to be found

Thanks

回答1:

Firstly you need to install: npm install --save @ionic/storage

The problem was in app.ts:

import {IonicStorageModule} from '@ionic/Storage';

Capital 'S' instead of non capital 's':

from '@ionic/Storage'

instead of:

from '@ionic/storage'

No idea why the compiler wouldn't catch that if it's a problem, but it didn't.

Thanks to @chairmanmow

回答2:

In my case, I forgot to add the following in app.module.ts

import { IonicStorageModule } from '@ionic/storage';

@NgModul({ 
  ..., 
  Imports: [
  ...
    IonicStorageModule.forRoot()
],

回答3:

first do this npm install --save @ionic/storage

I managed to get this working using this ..

Inside app.module.ts

import { Storage } from '@ionic/storage';

And then ...

providers: [{provide: ErrorHandler, useClass: IonicErrorHandler}, Storage]

And then in my page.ts

import { Storage } from '@ionic/storage';

In the constructor ...

public storage: Storage

And then within the guts of my code ..

this.storage.get('date').then((value) => {
  // blah
});

回答4:

I had the same issue. I added this to app.module.ts:

import { IonicStorageModule } from '@ionic/storage';

And, this to imports parts of the app.module.ts:

IonicStorageModule.forRoot(),