ionic run android gives Property … does not exist on type ‘{ [key: string]: AbstractControl; }’

https://forum.ionicframework.com/t/property-does-not-exist-on-type-key-string-abstractcontrol/65783

http://stackoverflow.com/questions/39881367/property-does-not-exist-on-type-key-string-abstractcontrol/39886710

I Test Finish:

1、In ts files, still use   loginForm: FormGroup;

2、loginForm.controls.password.valid   -> loginForm.get(‘password’).valid