dropdownDecoration property Null safety

1. dropdown_button2 package
2. documentation
3. dropdown_button2
4. DropdownButton2<T>
5. dropdownDecoration property

DropdownButton2 class

1. Constructors
2. DropdownButton2
3. Properties
4. alignment
5. autofocus
6. barrierColor
7. barrierDismissible
8. barrierLabel
9. buttonDecoration
10. buttonElevation
11. buttonHeight
12. buttonPadding
13. buttonWidth
14. customButton
15. customItemsHeight
16. customItemsIndexes
17. disabledHint
18. dropdownDecoration
19. dropdownElevation
20. dropdownFullScreen
21. dropdownMaxHeight
22. dropdownOverButton
23. dropdownPadding
24. dropdownWidth
25. enableFeedback
26. focusColor
27. focusNode
28. formFieldCallBack
29. hashCode
30. hint
31. icon
32. iconDisabledColor
33. iconEnabledColor
34. iconOnClick
35. iconSize
36. isDense
37. isExpanded
38. itemHeight
39. itemPadding
40. items
41. key
42. offset
43. onChanged
44. onMenuStateChange
45. openWithLongPress
46. runtimeType
47. scrollbarAlwaysShow
48. scrollbarRadius
49. scrollbarThickness
50. searchController
51. searchInnerWidget
52. searchMatchFn
53. selectedItemBuilder
54. selectedItemHighlightColor
55. style
56. underline
57. value
58. Methods
59. createElement
60. createState
61. debugDescribeChildren
62. debugFillProperties
63. noSuchMethod
64. toDiagnosticsNode
65. toString
66. toStringDeep
67. toStringShallow
68. toStringShort
69. Operators
70. operator ==