I'm a junior and I have a question. 

I need to communicate to the devs this business rule: "The contract upload button should be disabled once the contract is approved by the administrator" 

There are many more rules similar to this that disable parts of the UI based on certain conditions. 

Now it's fine and dandy to just write this rule out, but what is the correct UML diagram to visually represent a complicated series of rules around the disabling and appearance of UI elements? 

Thanks for your time,