For cycle always give same output

Question

1. Summarize the problem

The following for cycle keeps on running as i want, but always give me the same clicked button that is "0". It does not give me an error. But by playing the game i can see that it's always the same number.

2. Describe what you've tried

I've tried searching around the internet for people like me. but sadly i couldn't find anything.

3. Show some code

Code that i'm talking about.

    int ButtonNum;

public void Start()
{
    for (int i = 0; i < ButtonsPage.Length; i++)
    {
        ButtonsPage[i].GetComponent<Button>().onClick.AddListener(delegate { ButtonClicked(ButtonNum); });
    }
}

public void ButtonClicked(int i)
{
    Debug.Log("Clicked" + i);
    if (WhichType == "Nose")
    {
        NoseColor.sprite = NosesColor[i];
        NoseOutline.sprite = NosesOutline[i];
    }
    //ButtonNum will be used to say which one is clicked. Still haven't add it though cause i wanted to fix this problem before
}

TBH I don't see any code producing any output. Also what is `ButtonNum`? — Guru Stron, Oct 22 '22 at 20:03
by output i meant the "add listener". ButtonNum should send with the listener the number of the clicked button — Karma idk, Oct 22 '22 at 20:51
How is it supposed to send it? Can you please add the relevant code (i.e. for `ButtonClicked` and `ButtonNum` declaration) — Guru Stron, Oct 22 '22 at 20:54
Does this answer your question? [Captured variable in a loop in C#](/q/271440/90527) — outis, Oct 23 '22 at 10:45

score 3 · Accepted Answer · answered Oct 22 '22 at 21:10

You are not modifying ButtonNum in any way, I assume the goal is to use i as button number, try changing your code to:

public void Start()
{
    for (int i = 0; i < ButtonsPage.Length; i++)
    {
        var temp = i;
        ButtonsPage[i].GetComponent<Button>().onClick.AddListener(delegate { ButtonClicked(temp); });
    }
}

Temporary variable is required due to how closures work in C#.

For cycle always give same output

1 Answers1