MouseClickHandler returns an instance of the struct.

MouseCursorHandler returns an instance of the struct.

ScreenChangeHandler returns an instance of the struct.

TestHandler returns an instance of the struct.

MouseClickHandlerStruct is the handler for mouse clicks.

MouseCursorHandlerStruct is the handler for mouse cursor movements.

ScreenChangeHandlerStruct is the handler for screen changes.

TestHandlerStruct is a test handler.

Instance is the main interface for a handler for the tracker.