horizontalMargin property
The horizontal margin between the edges of the table and the content in the first and last cells of each row.
When a checkbox is displayed, it is also the margin between the checkbox the content in the first data column.
This value defaults to 24.0 to adhere to the Material Design specifications.
If checkboxHorizontalMargin is null, then horizontalMargin is also 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.
Implementation
final double horizontalMargin;