Using Event Delegate to pass an argument to a button.onClick function

[redmotion]

I can add a function via code to a series of instantiated prefabs with this:-

1. UIButton third = assignmentEntry.transform.GetChild(2).GetComponent<UIButton>(); // gets the button component
2.                        
3. EventDelegate.Set( third.onClick, onClickAssignmentListEntry );  // adds the onClickAssignmentListEntry function fine

However, I want the function to receive an argument so I can identify which button out of the prefabs was pressed ( each will be given an individual number).

I am aware that I need to use the EventDelegate.Parameter to add these arguments before setting the event delegate, however I can’t work out how this should be structured.

Ideally the function would be:-

1. public void onClickAssignmentListEntry ( int entry number ) {
2.         // each button will have it’s own entry number
3. }

How do I create an event delegate to enable the function onClickAssignmentListEntry to be passed an integer ( or a string that I can cast to an integer)?

Many thanks in advance.

[redmotion]

After watching this https://www.youtube.com/watch?v=K3lvXIvJFKc

I decided to cheat (e.g.: avoid the first approach using eventdelegate) and use:

1. UIButton third = assignmentEntry.transform.GetChild(2).GetComponent<UIButton>();
2. third.name =   i.ToString(); // setting each button name to a unique number (i) in the for loop
3. EventDelegate.Set( third.onClick, onClickAssignmentListEntry )

and changed the target function to:-

1. public void onClickAssignmentListEntry (  ) {
2. Debug.LogWarning ( UIButton.current.name +" button pressed" );
3.         }

Getting me the same result without the hoop jumping required with event delegate parameters.

Feel free to post a better solution!

[ArenMook]

You can currently pass literals via code in 3.7.0 like so:

1. using UnityEngine;
2.  
3. public class Test : MonoBehaviour
4. {
5.         void Start ()
6.         {
7.                 UIButton btn = GetComponent<UIButton>();
8.                 EventDelegate del = new EventDelegate(this, "MyClick");
9.                 del.parameters[0].value = 123;
10.                 EventDelegate.Set(btn.onClick, del);
11.         }
12.  
13.         void MyClick (int someValue)
14.         {
15.                 Debug.Log(someValue);
16.         }
17. }

In previous versions you have to use properties or anonymous delegates instead (which is technically shorter code anyway).

1. using UnityEngine;
2.  
3. public class Test : MonoBehaviour
4. {
5.         void Start ()
6.         {
7.                 UIButton btn = GetComponent<UIButton>();
8.                 EventDelegate.Set(btn.onClick, delegate() { MyClick(123); });
9.         }
10.  
11.         void MyClick (int someValue)
12.         {
13.                 Debug.Log(someValue);
14.         }
15. }

[redmotion]

Thanks Aren, that will make my code less of a hack job!