Scripting a menu [Noob Problems]

Well, I have a button "menu" on the UI and i want press it to show a canvas. I have this code:

Code (CSharp):

1.  
2. using UnityEngine;
3. using System.Collections;
4.  
5. public class menuScript : MonoBehaviour {
6.  
7.     public GameObject PauseUI;
8.     public GameObject menu;
9.     private bool paused = false;
10.  
11.     void Start () {
12.         PauseUI.SetActive(false);
13.     }
14.  
15.     void Update () {
16.         if (Input.GetButtonDown("menu")) {
17.             paused = ! paused;
18.         }
19.         if (paused)
20.         {
21.             PauseUI.SetActive(true);
22.             Time.timeScale = 0;
23.         }
24.         if (!paused)
25.         {
26.             PauseUI.SetActive(false);
27.             Time.timeScale = 1;
28.         }
29.     }
30. }
31.  

When I asociated the "menu" button with my public gameobject menu, but when i press it canvas still hiden

 

Code (csharp):

1.  
2. (Input.GetButtonDown("menu"))
3.  

this refers to a keyboard button press...

how to setup UI buttons: https://unity3d.com/learn/tutorials/modules/beginner/ui/ui-button?playlist=17111

 

Many many thanks

 

Sooo the code will be:

Code (CSharp):

1. using UnityEngine;
2. using System.Collections;
3.  
4. public class menuScript : MonoBehaviour {
5.  
6.     public GameObject PauseUI;
7.     private bool paused = false;
8.     void Start () {
9.         PauseUI.SetActive(false);
10.     }
11.  
12.   public void onClick()
13.     {
14.         paused = !paused;
15.         if (paused)
16.         {
17.             PauseUI.SetActive(true);
18.             Time.timeScale = 0;
19.         }
20.         if (!paused)
21.         {
22.             PauseUI.SetActive(false);
23.             Time.timeScale = 1;
24.         }
25.     }
26. }