onUnmount method

void onUnmount()

Called before removal from tree.

Implementation

void onUnmount() {
  for (final dispose in _disposeCallbacks) {
    dispose();
  }
  _disposeCallbacks.clear();
  _mounted = false;
  _onNeedRebuild = null;
  _manageStyles(false);
  ComponentRegistry.instance.unregister(this);
}