Hi I want to add a Horizontally scrollable menu just like in clash of clans,

I am actually building a game currently, I have added limited number of objects to the screen,when I tap on the specified objects it gets added to the screen and I am free to place it anywhere by dragging it,
but when I add more objects I want them to be accesible by scrolling them horizontally just like in clash of clans village editor mode this is how my game looks presently.
https://drive.google.com/open?id=1kye2H-ghMFWz9fwDg22KzeMc7WqfPlBD
heres a short video of layout of my game
I have actually added images to screen at the bottom when I tap on a particular image, it gets added to screen in the form of a physics object.I am free to move it anywhere on the screen