Use case

Currently, the DataTable column widths aren't flexible unless you only have one column that contains only text:

if (dataColumnIndex == _onlyTextColumn) {
    tableColumns[displayColumnIndex] = const IntrinsicColumnWidth(flex: 1.0);
} else {
    tableColumns[displayColumnIndex] = const IntrinsicColumnWidth();
}

It would be nice to be able to specify a column of your choice to have flexible width.

Proposal

Add a field like flexibleColumnIndex to DataTable that can be used to set the IntrinsicColumnWidth flex to 1.0 if the field is non-null.

I can put in a PR for this if this makes sense.