Best way to handle multiple buttons?

Sorry for not providing complete example code, but this is how I would solve the problem:

1. Create a prefab (http://docs.unity3d.com/Manual/Prefabs.html) as a template for the button.

2. In GUI, create horizontal layout group (http://docs.unity3d.com/460/Documentation/Manual/script-HorizontalLayoutGroup.html) as a parent for all these buttons.

3. Implement the manager (http://blog.codinghorror.com/i-shall-call-it-somethingmanager/) which contains references (http://docs.unity3d.com/ScriptReference/SerializeField.html) for the prefab of the button and parent for button instance (the manager component can be put on the parent itself).

4. In Awake (https://unity3d.com/learn/tutorials/modules/beginner/scripting/awake-and-start) method I would instantiate the prefab for each button (http://docs.unity3d.com/Manual/InstantiatingPrefabs.html) and change their parents to the parent with layout (http://docs.unity3d.com/ScriptReference/Transform.SetParent.html)

5. For each instance, you can find the button script ( Button button = instance.GetComponent<Button>() ) and add listener to it's onClick method (http://docs.unity3d.com/460/Documentation/ScriptReference/UI.Button-onClick.html).

Notes:

• If you want to change content of the button, there are multiple ways:

  • Find the item (for example Text (http://docs.unity3d.com/ScriptReference/UI.Text.html) with GetComponentInChildren (http://docs.unity3d.com/ScriptReference/Component.GetComponentInChildren.html)) and change it

  • Implement special component for the button which is put on root and have instances for components which needs to change (that's how I would do it)

• For adding listener for the button, you can use C#'s anonymous function (https://msdn.microsoft.com/cs-cz/library/Bb882516%28v=VS.120%29.aspx) for example:

       public void CreateInstances()
       {
         for(int i = 0; i < 10; ++i)
         {
           GameObject prefabInstance = Object.Instantiate(buttonPrefab);
           Button button = prefabInstance.GetComponent<Button>();
           button.onClick.AddListener(() => { OnButtonClicked(i); });
         }
       }
       
       public void OnButtonClicked(int buttonIndex)
       {
         // ...
       }
  
  

 for (int i = 0; i <= 20; i++)
         {
             GameObject button = Instantiate(buttonTemplate);
 
             image = Resources.Load<Sprite>("iconsCPL/"+i.ToString());
             texturelist.Add(Resources.Load<Texture>("iconsCPL/" + i.ToString()));
             var prefabsimage = button.gameObject.transform.GetChild(0);
             prefabsimage.GetComponent<Image>().sprite = image;
 
 
             button.SetActive(true);
             button.GetComponent<ButtonListButt>().SetIndex(i);
             button.transform.SetParent(buttonTemplate.transform.parent,false);
             button.gameObject.GetComponent<Button>().onClick.AddListener(delegate () { PrintText(button); });
 
         }
 
     }
 
     public void PrintText(GameObject g) 
     {
         float i = g.GetComponent<ButtonListButt>().GetIndex();
         int index = g.GetComponent<ButtonListButt>().GetIndex();
         i = i / 25;