public bool interactable ;



using UnityEngine;
using System.Collections;
using UnityEngine.UI; // required when using UI elements in scripts

public class Example : MonoBehaviour { public Button startButton; public bool playersReady;

void Update() { // checks if the players are ready and if the start button is useable if (playersReady == true && startButton.interactable == false) { //allows the start button to be used startButton.interactable = true; } } }