wrapTextDirection property
Determines the order to lay children out horizontally and how to interpret
start and end in the horizontal direction.
Defaults to the ambient Directionality.
If the wrapDirection is Axis.horizontal, this controls order in which the children are positioned (left-to-right or right-to-left), and the meaning of the wrapAlignment property's WrapAlignment.start and WrapAlignment.end values.
If the wrapDirection is Axis.horizontal, and either the wrapAlignment is either WrapAlignment.start or WrapAlignment.end, or there's more than one child, then the wrapTextDirection (or the ambient Directionality) must not be null.
If the wrapDirection is Axis.vertical, this controls the order in which runs are positioned, the meaning of the wrapRunAlignment property's WrapAlignment.start and WrapAlignment.end values, as well as the wrapCrossAxisAlignment property's WrapCrossAlignment.start and WrapCrossAlignment.end values.
If the wrapDirection is Axis.vertical, and either the wrapRunAlignment is either WrapAlignment.start or WrapAlignment.end, the wrapCrossAxisAlignment is either WrapCrossAlignment.start or WrapCrossAlignment.end, or there's more than one child, then the wrapTextDirection (or the ambient Directionality) must not be null.
Implementation
final TextDirection? wrapTextDirection;