SignInScreenVM constructor Null safety

1. farmershands
2. signin_screen_vm
3. SignInScreenVM
4. SignInScreenVM constructor

SignInScreenVM class

1. Constructors
2. SignInScreenVM
3. Properties
4. hashCode
5. isChecked
6. passController
7. runtimeType
8. usernameController
9. Methods
10. findIDAction
11. noSuchMethod
12. onTapFindPassword
13. onTapSignIn
14. toString
15. Operators
16. operator ==