[OnMemberInvisible]

Attribute used for specifying a callback method to invoke when the member stops being visible in the inspector.

Examples

[ToggleLeft]
public bool showDetails;

[ShowIf(nameof(showDetails))]
[OnMemberInvisible(nameof(OnDetailsHidden))]
public string details = "Secret Details";

private void OnDetailsHidden()
{
    Debug.Log("Details field became hidden");
}