add method

ChartController add(
  1. ChartController ctrl
)

Add a controller to the group and wire it up for synchronization.

Implementation

ChartController add(ChartController ctrl) {
  if (_disposed || ctrl.isDisposed) return ctrl;
  _detachDisposedControllers();
  if (!_controllers.contains(ctrl)) {
    _controllers.add(ctrl);
    void listener() => _propagateChanges(ctrl);
    _listeners[ctrl] = listener;
    ctrl.addListener(listener);
  }
  return ctrl;
}