I'm playing on the Windows 10 Edition.
When I placed several Barrels on the wall in creative mode, the keg texture was like an open Barrel, but nobody opened it.

I have placed the Barrels next to each other, I have "left click"
(I changed my build button from right-click to left-click) and held it down. Minecraft placed the barrel right next to the other barrel, but opened the previous barrel at the same time. The barrel storage menu did not open, but the barrel texture.

After that I could repeat this process as often as I wanted and now I had lots of open barrels on my world.

You can "close" the barrel / texture again by clicking on the barrel to "open" it (open the menu, the barrel was already open) and then close the menu again to restore the barrel texture " normal "to do.