adding OnClick with a parameter to a button at runtime not working

i have the following code

Code (CSharp):

1.  
2.     public void OnClickMaterialChooserDir(int idx)
3.     {
4.         Debug.Log("OnClickMaterialChooserDir "+idx);
5.     }
6.  
7.     public void PopulateMaterialChooserPanel()
8.     {
9.         //Debug.Log("PopulateMaterialChooserPanel");
10.  
11.         string myPath = "Assets/Resources/Materials/";
12.         DirectoryInfo matdir = new DirectoryInfo(myPath);
13.  
14.         DirectoryInfo[] dirInfo = matdir.GetDirectories();
15.  
16.         //FileInfo[] info = dir.GetFiles("*.*");
17.         int i = 0;
18.         foreach (DirectoryInfo dir in dirInfo)
19.         {
20.             //ItemGameObject is my prefab pointer that i previous made a public property
21.             //and  assigned a prefab to it
22.             DefaultControls.Resources TempResource = new DefaultControls.Resources();
23.             GameObject buttonGO = DefaultControls.CreateButton(TempResource);
24.             buttonGO.AddComponent<LayoutElement>();
25.             Button dirButton = buttonGO.GetComponent<Button>();
26.             dirButton.onClick.AddListener(() => { OnClickMaterialChooserDir(i); }); //AddListener(delegate { OnClickMaterialChooserDir(i); });
27. Debug.Log("PopulateMaterialChooserPanel "+i);
28.             i++;
29.             Text text = dirButton.transform.GetChild(0).GetComponent<Text>();
30.             text.text = dir.Name;
31.             text.fontStyle = FontStyle.Bold;
32.             text.fontSize = 16;
33.  
34.             dirButton.transform.SetParent(_MaterialChooserScrollViewContent, false);
35.         }
36.     }

It creates buttons in a scrollview based on the directories in a resources folder, and it works, the buttons are created, the correct label text is set and i can click.
but when i get the callback to OnClickMaterialChooserDir idx is always 3 (the number of directories in this case)
i got the idea for the code from here
https://answers.unity.com/questions/1288510/buttononclickaddlistener-how-to-pass-parameter-or.html
i tried both the delegate method and the one you see here and both give the same result
does anyone know what's wrong?
thx
PS, PopulateMaterialChooserPanel() is only called from Start

i suspect the problem is the buttons are created at run time, not sure

 

ok i found it, i think if i had done a 'new Int()' instead of 'i' it would have worked, anyhow this is want i really wanted and it works

Code (CSharp):

1.     public void OnClickMaterialChooserDir(string dir)
2.     {
3.         Debug.Log("OnClickMaterialChooserDir "+dir);
4.         //PopulateMaterialChooserPanel(dir);
5.     }
6.  
7.     public void PopulateMaterialChooserPanel(string baseDir)
8.     {
9.         //Debug.Log("PopulateMaterialChooserPanel");
10.  
11.         string myPath = "Assets/Resources/Materials/"+ baseDir;
12.         DirectoryInfo matdir = new DirectoryInfo(myPath);
13.  
14.         DirectoryInfo[] dirInfo = matdir.GetDirectories();
15.  
16.         FileInfo[] fileInfo = matdir.GetFiles("*.mat");
17.  
18.         foreach (DirectoryInfo dir in dirInfo)
19.         {
20.             //ItemGameObject is my prefab pointer that i previous made a public property
21.             //and  assigned a prefab to it
22.             DefaultControls.Resources TempResource = new DefaultControls.Resources();
23.             GameObject buttonGO = DefaultControls.CreateButton(TempResource);
24.             buttonGO.AddComponent<LayoutElement>();
25.             Button dirButton = buttonGO.GetComponent<Button>();
26.             dirButton.onClick.AddListener(() => { OnClickMaterialChooserDir(dir.Name); }); //AddListener(delegate { OnClickMaterialChooserDir(i); });
27.             Text text = dirButton.transform.GetChild(0).GetComponent<Text>();
28.             text.text = dir.Name;
29.             text.fontStyle = FontStyle.Bold;
30.             text.fontSize = 16;
31.  
32.             dirButton.transform.SetParent(_MaterialChooserScrollViewContent, false);
33.         }
34.     }

 

@steveh2112

I didn't read your code properly but:

Code (CSharp):

1. // AddListener(delegate { OnClickMaterialChooserDir(i);

If you want to use this, that "i" must be a local variable in that loop for it to work... it is called C# closure I think.