Ionic 2. Checking permissions

Following with what was discussed in the last entry in Android since Marshmallow is necessary to check at run time the permissions cataloged how to dangerous and read or write in the external storage is one of them. In the case at hand, for restore the backup, as the app writes in the sandbox it isn't necessary to check the permissions. 

For check the permissions, we use the diagnostic plugin and we will use the same plugin for check permissions for access to location, sensors, phone, contacts, etc... but in this entry I only will write over the access to the external storage.

Well, first we install the plugin

   ionic plugin add cordova.plugins.diagnostic

And

   npm install --save @ionic-native/diagnostic

And we create a service to manage all the permissions

   ionic g provider PermissionsService

And we edit ../providers/permissions-service.ts and write

import { Injectable } from '@angular/core'; import { Platform } from 'ionic-angular'; import 'rxjs/add/operator/map'; import { Diagnostic } from '@ionic-native/diagnostic'; /* Generated class for the PermissionsService provider. See https://angular.io/docs/ts/latest/guide/dependency-injection.html for more info on providers and Angular 2 DI. */ @Injectable() export class PermissionsService { constructor(public platform: Platform, public diagnostic: Diagnostic) { }
isAndroid() { return this.platform.is('android'); }
checkWritePermission(): Promise<boolean> return new Promise (resolve => if (this.isAndroid) { this.diagnostic.isExternalStorageAuthorized() .then(authorized => { if(authorized) { resolve(true); } else { this.diagnostic.requestExternalStorageAuthorization() .then(authorization => { resolve (authorization == this.diagnostic.permissionStatus.GRANTED); }); } }); } }); } }

And we use it

createBackup () { if (this.permissions.isAndroid()) {< this.permissions.checkWritePermission().then(permission => { this.backup(); }, error => { console.log(error); }); } }

And the result looks like this