Here i want to explain to you how you would create a button with the default color gray, and as long as the user is clicking on the button it will change its color to black (the default frame-background is lightGray).
To make this possible the button needs 1 onClick event, 1 onClickUp event and 1 onLoseFocus event.
Very interesting sidetip: events can hold multiple functions!
Example snippet:
This means you can create a function wich handles only the coloring side of your button, and if your button also needs some logic you just create your own unique function for that and add it to your button.
With this knowledge we create now a function where we pass a button-object as parameter and this will setup the coloring of our button:
Example snippet:
Now you've got a function which sets your buttons up.