CowSettingsScreenVM constructor Null safety

1. farmershands
2. cow_settings_screen_vm
3. CowSettingsScreenVM
4. CowSettingsScreenVM constructor

CowSettingsScreenVM class

1. Constructors
2. CowSettingsScreenVM
3. Properties
4. cowRows
5. cows
6. groupNameTextControllers
7. groupRows
8. groupSelectedRows
9. hashCode
10. hasListeners
11. refreshController
12. runtimeType
13. selectedCows
14. selectedTabIndex
15. tabController
16. Methods
17. addListener
18. dispose
19. fetchCows
20. init
21. noSuchMethod
22. notifyListeners
23. onLoading
24. onRefresh
25. onReorderGroups
26. removeListener
27. toString
28. updateDataTableRows
29. Operators
30. operator ==