TooltipState constructor Null safety

1. Flutter
2. material
3. TooltipState
4. TooltipState constructor

TooltipState class

1. Constructors
2. TooltipState
3. Properties
4. context
5. hashCode
6. mounted
7. runtimeType
8. widget
9. Methods
10. activate
11. build
12. createTicker
13. deactivate
14. debugFillProperties
15. didChangeDependencies
16. didUpdateWidget
17. dispose
18. ensureTooltipVisible
19. initState
20. noSuchMethod
21. reassemble
22. setState
23. toDiagnosticsNode
24. toString
25. toStringShort
26. Operators
27. operator ==