computeDistanceToActualBaseline method Null safety

  1. @protected
double? computeDistanceToActualBaseline(
  1. TextBaseline baseline

Returns the distance from the y-coordinate of the position of the box to the y-coordinate of the first given baseline in the box's contents, if any, or null otherwise.

Do not call this function directly. If you need to know the baseline of a child from an invocation of performLayout or paint, call getDistanceToBaseline.

Subclasses should override this method to supply the distances to their baselines. When implementing this method, there are generally three strategies:


double? computeDistanceToActualBaseline(TextBaseline baseline) {
  assert(_debugDoingBaseline, 'Please see the documentation for computeDistanceToActualBaseline for the required calling conventions of this method.');
  return null;