Hi,
does destructor unbind events ???
Here the description in the doc :
void destructor (); //removes a Grid instance and releases occupied resources
Destructor removes any html event handlers which was added by component.
The custom event handlers are not removed directly, but due to their nature they will be removed by the garbage collector after component destruction.
Basically anything which can contains references outside of the component is nullified/deleted during destructor call to allow correct memory releasing.