typedef struct{ Uint8 type; Uint8 which; Uint8 button; Uint8 state; } SDL_JoyButtonEvent;
SDL_JoyButtonEvent is a member of the SDL_Event union and is used when an event of type SDL_JOYBUTTONDOWN or SDL_JOYBUTTONUP is reported.
A SDL_JOYBUTTONDOWN or SDL_JOYBUTTONUP event occurs when ever a user presses or releases a button on a joystick. The field which is the index of the joystick that reported the event and button is the index of the button (for a more detailed explaination see the Joystick section). state is the current state or the button which is either SDL_PRESSED or SDL_RELEASED.