How to listen for a key being pressed in lua?

[Nalif]

I have a button that does something when it's clicked by the left mouse button. I was to listen for a keypress ( alt ) and have that button do something else when alt is being held down. How can I do this?

 

[Pinco]

it's all managed inside the client, there is a function but works only for hotbars and can't be modified.

 

[Nalif]

Pssh. That's lame. Atleast you saved me a lot of time Thanks!