Unregister button callbacks

Unity Engine
1

I’m setting up a window with a bunch of buttons nested in a listView.

WWhen binding items to the listView I do the following :

arg1.Q<Button>("PrefabButton").clickable.clicked += () => OpenPrefab(prefab);

The issue is, as items in the list gets recycled and binded again, the clicked event is never cleaned, so it keeps on adding callbacks to the list.

Is there a way to remove callbacks from this event? I’ve tried using -= but it doesn’t seem to work, probably because the “prefab” variable is different on each bind.

2

How about using .userData for event handling?

  1. Register click event in makeItems using the userData of button itself.
var button = your button
button.clickable.clicked += () => OpenPrefab(button.userData);
  1. Change userData in bindItems.
1 Like
3

Hello,

when subscribing to a delegate with a Temporary function (...+= () =>...), you can not unsubscribe that temp function.

Typically you pass in a stardard function:

//subscribe
arg1.Q<Button>("PrefabButton").clickable.clicked +=OpenPrefab;

...
void OpenPrefab()
{
//Get the correct prefab
}
...

//unsubscribe
arg1.Q<Button>("PrefabButton").clickable.clicked -=OpenPrefab;

typically when you run into issues, like yours above, it means you should re-structure your code.

1 Like
4

okay that’s what I thought, thanks for the confirmation.

@Kichang-Kim : I didn’t thought of that, but that seems like a good way to adress my issues, thanks.