unregister abstract method

void unregister(CallbackWithReturn<CallbackInputType, CallbackReturnType> callback)

Removes a previously registered callback.

After unregistering, the callback will no longer be invoked. If the callback was not registered, this operation is a no-op.

Example:

final callback = (int n) => n * 2;
handler.register(callback);
handler.unregister(callback); // Removes the callback

Implementation

void unregister(
    CallbackWithReturn<CallbackInputType, CallbackReturnType> callback);