setRoot does not work after using SDK - ionic2

Question

Ionic version:
[ ] 3.X
Current behavior:
In my Application I have three options for login AWS Cognito Identity Provider , Google , facebook.
After successful login authentication when user moves to the Drivesetup Page, I set the Drivesetup Page as a root page (setRoot) but I'm facing a problem that user can easily go back again on login screen using mobile back button.
Expected behavior:
I am expecting that user can't go back to the login page by pressing mobile back button when I'm using setRoot to navigate the screen from login to dashboard.
Steps to reproduce:
Code Included.
GitHub Repo:-
https://github.com/saurabhschauhan/demoApp
Related code:
constructor(
public nav: Nav,
public app: App,
public navCtrl: NavController,) {
}
this.awsCredentialsService.login(data)
.then((awsCredentialsServiceResponse) => {
if (awsCredentialsServiceResponse['status'] == 'success') {
//navigate page
this.navCtrl.setRoot('DrivesetupPage');
//OR
//this.app.getRootNav().setRoot('DrivesetupPage');
//or
//this.nav.setRoot('DrivesetupPage');
this.toasterService.showToaster(email + `Logged in successfully`);
} else {
console.log('any other error');
}
})
Other information:
I had tried two more options this.app.getRootNav().setRoot('DrivesetupPage') and this.nav.setRoot('DrivesetupPage'); but both are not working for me.
Ionic info:
#ionic/cli-utils : 1.13.0
ionic (Ionic CLI) : 3.13.0
global packages:
cordova (Cordova CLI) : 7.1.0
local packages:
#ionic/app-scripts : 3.0.0
Cordova Platforms : android 6.3.0
Ionic Framework : ionic-angular 3.7.1
System:
Android SDK Tools : 26.1.1
Node : v6.9.1
npm : 3.10.8
OS : Linux 3.16
Misc:
backend : pro
Thank you.