index property Null safety

1. baguette
2. TabsScreenWidget
3. TabsScreenWidget
4. index property

TabsScreenWidget class

1. Constructors
2. TabsScreenWidget
3. Properties
4. data
5. hashCode
6. index
7. key
8. runtimeType
9. Methods
10. createElement
11. createState
12. debugDescribeChildren
13. debugFillProperties
14. getName
15. noSuchMethod
16. toDiagnosticsNode
17. toString
18. toStringDeep
19. toStringShallow
20. toStringShort
21. Operators
22. operator ==