performLayout method

@override Size performLayout(BoxConstraints constraints)

Hook for subclasses to perform layout within the given constraints.

Implementation

@override
Size performLayout(BoxConstraints constraints) {
  final tabBar = widget as TabBar;
  var w = 0;
  for (var i = 0; i < tabBar.labels.length; i++) {
    final label = tabBar.labels[i];
    final text = ' [ $label ] ';
    w += text.characters.length;
  }
  return constraints.constrain(Size(w, 1));
}