OnClick on button from code

I can't find how to detect clicks on a button from code, like mouse down, mouse up after mouse down?

Thanks

 

Don't use Button, use EventTrigger instead.

 

This seems counter-intuitive as the first time i hear about it. Is there any example?

Thanks!

 

Like this?

Code (CSharp):

1. void Start()
2.     {
3.         Button b = gameObject.GetComponent<Button>();
4.         b.onClick.AddListener(delegate() { StartGame("Level1"); });
5.     }
6.    
7.     public void StartGame(string level)
8.     {
9.         Application.LoadLevel(level);
10.     }

 

Not working here =(

Code (csharp):

1.  
2. public void SetupButton () {
3.      var button = transform.GetComponent<Button>();
4.      button.onClick.AddListener(delegate () { this.ButtonClicked(); });
5. }
6.  
7. public void ButtonClicked () {
8.      _buildStructureGUI.SelectedPool = _structurePool;
9. }
10.  

 

Do you need to set it up from code? e.g. Do you have procedurally generated buttons?

Setting it up in the Editor is much easier (and the 'expected' use).

 

Its procedurally =/

 

Have you tried referring directly to the function as a delegate, as opposed to creating an in-line delegate that calls the function?
(I haven't, but I feel like this should work)

Code (csharp):

1.  
2. public void SetupButton () {
3.      var button = transform.GetComponent<Button>();
4.      button.onClick.AddListener(this.ButtonClicked);
5. }
6.  
7. public void ButtonClicked () {
8.      _buildStructureGUI.SelectedPool = _structurePool;
9. }
10.  

I'm not sure how one would add parameters to this. I would've expected that AddListener would have a second parameter that could become the callback's parameter (equivalent to that third 'box' in the Inspector).

 

I've tried too, but without success ... I have the impression that it is necessary to mark the delegate as persistence ... But I do not know how ...

 

Same thing, still trying to figure out how to have the handler function receive the actual button, or anything else as a parameter.

I think it can be done using the new UnityAction, but I can't manage to get it right.

 

You just need to remove the parentheses from where you are setting delegate...

This is working fine for me...

Code (csharp):

1.  
2.     public void setupBtn()
3.     {
4.         string param = "bar";
5.         btn.GetComponent<Button>().onClick.AddListener(delegate { btnClicked(param); });
6.     }
7.        
8.     public void btnClicked(string param)
9.     {
10.         Debug.Log("foo " + param);
11.     }
12.  
13.  

Outputs "foo bar", as one would expect.

 

Thank you ldb: it works.

For curiosity, in the Editor Inspector, the OnClick listener of the button does not appear. Is it normal?

 

I noticed the same problem. Listener does not appear, but it works. Looks like the list isn't being refreshed. I reported this as a bug.

 

thanks Amaranth

 

That reminds me! Found an easier way to do what we all seem to be trying to do. It turns out that Unity 4.6 has a built-in feature for this. This is how I used it:

1. In the Project Tab, create a new script called MyEventListener.
2. Paste this code into the script:

Code (CSharp):

1. using UnityEngine;
2. using UnityEngine.EventSystems;
3.  
4. public class MyEventListener : MonoBehaviour, IPointerClickHandler
5. {
6.     private float clickTime;            // time of last click
7.     private int clickCount=0;         // current click count
8.     public bool onClick = true;            // is click allowed on button?
9.     public bool onDoubleClick = false;    // is double-click allowed on button?
10.    
11.     public void OnPointerClick(PointerEventData data)
12.     {        
13.         // get interval between this click and the previous one (check for double click)
14.         float interval = data.clickTime - clickTime;
15.  
16.         // if this is double click, change click count
17.         if (interval < 0.5 && interval > 0 && clickCount != 2)
18.             clickCount = 2;
19.         else
20.             clickCount = 1;
21.  
22.         // reset click time
23.         clickTime = data.clickTime;
24.            
25.         // single click
26.         if (onClick && clickCount == 1)
27.         {
28.             // enter code here
29.         }
30.    
31.         // double click
32.         if (onDoubleClick && clickCount == 2)
33.         {
34.             // enter code here
35.         }
36.    
37. }

3. Drag this script on to your button game object (or attach it via code).
4. Set the onClick and onDoubleClick bools (you may want one click on some objects, double-click on others, etc)

(updated with small changes)

 

@amaranth Will this script work for Touch Input. if not what changes i should make ?

 

But how the click is associated with touch ? im bit confused here . well atleast i should try it out first hehe

 

Thanks for the awesome code amaranth! I know it's a year later and big changes have come about, but in Unity 5.1 I got the following error. My hack(see attached script) was to hit the button and have it play an Animator trigger animation. Scripting is not my forte as you can tell. I have an 'Idle' animation that is transitioned to a 'Throw' animation. The 'Throw' animation has a trigger parameter. Every time the button is hit, the 3D player throws a ball. It would be a milestone to get this part working. Thanks in anticipation

 

This approach is the closest I've found to the intended goal: pass a parameter in the onClick method. Very nice!

 

I know thread is old but I'm trying to assign click handlers to UI buttons that are in a prefab and loaded at runtime. But it's not working. I use the same way as described by ldb above.

Is there anything else I need to take care of? An EventSystem exists in the scene (although I'm not sure it's really needed for this).

My code looks like this:

Code (CSharp):

1. GameObject uiObj = ResourceUtil.InstantiatePrefab("Prefabs/UI/Main Menu UI", "UI");
2. uiObj.transform.SetParent(gameObject.transform, false);
3. Button[] buttons = uiObj.GetComponentsInChildren<Button>();
4. foreach (Button button in buttons)
5. {
6.     button.onClick.AddListener(() => OnUIButtonClick(button));
7. }
8.  
9. private void OnUIButtonClick(Button button)
10. {
11.     Log.Debug("OnUIButtonClick: " + button);
12. }

 

Nevermind! I had to add a GraphicRaycaster to the Canvas object that is used as a parent for my menu object. Now it works.

 

//first we have using the UI, so...
Using UnityEngine.UI;
//and before ..in Start void....
public Button yourButton;//yourButton is namebutton
public Button yoursecondButton ;
void Start ()
{
yourButton .onClick .AddListener (() => { // yourButton must be like first part

print ("hello people");//print hello people or anything in massagebar
//or
Application .LoadLevel ("urSence");//load a sense after on click and ursence is name sence
//or
yoursecondButton .enabled = false or true;//yoursecondButton is on or off

});



}

 

Code (CSharp):

1.  public Transform DebugPanel;
2.     public GameObject DebugText;
3.  
4.  
5.     void Start()
6.     {
7.         var db = new DataService();
8.         foreach (var ss in db.DBUsers)
9.         {
10.             GameObject Local = Instantiate(DebugText);
11.  
12.             Local.GetComponentInChildren<Text>().text = "User: " + ss.idUsers + " " + ss.Login;
13.             Local.GetComponentInChildren<Button>().onClick.AddListener(delegate () { ShowWhatWasCliked(ss); });
14.             Local.transform.SetParent(DebugPanel);
15.         }
16.     }
17.  
18.     private void ShowWhatWasCliked(DBUsers ss)
19.     {
20.         Debug.Log(ss.Login);
21.     }

 

Here is a simple video demonstration of how to add onclick event to button

 

does this work for a 2D game?

 

Yes, this has to do with the UI, nothing specifically to do with 2D or 3D.

 

if i have 100 btn and i need one function onclick for to 100 btn what is the solution for that

 

why?