Cancels the timer. If the timer is not active, this does nothing.
Returns whether the timer is currently active (i.e., has been started and not yet fired or canceled).
True if the timer is active, false otherwise.
Restarts the timer. If the timer is not active, this starts it.
Starts the timer. If the timer is already active, this does nothing.
A simple timer that calls a callback after a specified delay.