I want to add total 5 button at bottom of screen but only four will be visible at first time loading of nib.

and if user press first button it will be disappear with animation and second button will come at place of first . and now in screen one more button (button 5 ) at last.

to make it more clear i am adding image.

screen 1. when nib loaded first time.

screen 2. when button 1 pressed.

screen 3. when button 2 pressed.

![enter image description here](https://i.stack.imgur.com/yvtV5.png)