dispose method
- @mustCallSuper
Discards any resources used by the object. After this is called, the object is not in a usable state and should be discarded (calls to addListener will throw after the object is disposed).
This method should only be called by the object's owner.
Implementation
@mustCallSuper
void dispose() {
assert(_debugAssertNotDisposed());
assert(() {
_debugDisposed = true;
return true;
}());
_listeners = _emptyListeners;
_count = 0;
}