press button on canvas with gamepadkey?

hello everyone,

im working in a unity project with the oculus rift.
i have a canvas in my game with a button on it (to launch the game.)

im also using a xbox controller.
how can i press the button on my canvas with the A key on my game pad??
i cant use the mouse because of the controller. and i added a On click () action to the button

here is my setup:


some good links in there by the looks of it