UI Change Source Image

Hi I'm new to unity and can't seem to find an answer to this question which works for me:

Basically, I have a button called No which has a source image called Button Not Over.

I want to make it so that when the mouse is hovered over this button, the source image changes to one called Button Over and when the mouse is no longer over the button, the source image reverts to Button Not Over.

Any help is greatly appreciated.

 

MouseOver image can be changed in button component in inspector.

 

Onmouseover doesn't seem to be being run when I attach the script to the button?

 

Is it because you're overriding onMouseOver in the attached script?

 

This is the script which I added to the button

 

Well, remove it. Use this:

 

I'm still getting nothing. I set the target graphic as the button which the component is on and I set the sprite as the highlighted sprite.