text_block library Null safety

TODO: Remove this file in the next breaking release, because implementation files should be located in the src folder, https://bit.ly/3fA23Yz.

Classes

EditableTextBlock
RenderEditableTextBlock

Constants

arabianRomanNumbers → const List<int>
[1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1]
romanNumbers → const List<String>
['M', 'CM', 'D', 'CD', 'C', 'XC', 'L', 'XL', 'X', 'IX', 'V', 'IV', 'I']