checkboxHorizontalMargin property
final
Horizontal margin around the checkbox, if it is displayed.
If null, DataTableThemeData.checkboxHorizontalMargin is used. If that is also null, then horizontalMargin is used as the margin between the edge of the table and the checkbox, as well as the margin between the checkbox and the content in the first data column. This value defaults to 24.0.
Implementation
final double? checkboxHorizontalMargin;