MacosTabController constructor
Coordinates tab selection for MacosSegmentedControl and MacosTabView.
The index property is the index of the selected tab.
A stateful widget that builds a MacosSegmentedControl and a MacosTabView can create a MacosTabController and share it between them.
Implementation
MacosTabController({
int initialIndex = 0,
required this.length,
}) : assert(length >= 0),
assert(initialIndex >= 0 && (length == 0 || initialIndex < length)),
_index = initialIndex,
_previousIndex = initialIndex;