angular/material

Hi ~ I have form in my code, when user complete the form and click "Add" button, the data inserted to the array I created in controller. then I use ng-repeat to show the items in the list below the form. This action happened in the same time and in the same page. When items added to the array (and also to the list), each item has two option, delete and edit. When user click on the edit button, the data shown up in the form and user can edit it. Now, I have two problem. 1. I want to add class for (for example) 3 seconds to the latest entered item. I used $last but it has a problem, which when I delete the last one, It give the class to the last item before deleted one and I don't want this. 2. I want to add class to the item which user click on its edit button. How can I do these things?? Thanks