There are several reasons why someone would like to hide the user interface (UI) or so-called HUD in Battlefield 4. Maybe you simply want to take beautiful screenshots of BF4, but without the interface. Storyteller and video editors often want to have the editing material without the user interface or HUD. So, if you are one of those who would like to know how to disable the HUD. Here is the solution…
You need to type a command into the game console. You can open the console in Battlefield 4 with the tilde key (~). Once you opened the console, you need to type in:
UI.drawEnable 0
And if you want to bring back the UI, you need to type in:
UI.drawEnable 1
I think you could also write the word “false” instead of 0 and the word true instead of 1.
You could even put the command into a config file to have these settings on start-up but in this case here it does not make sense, as you would also remove the game menu and when you start the game, it would be harder to go into the battle. I do not suggest to use a config file in this case here, but it is still worth to mention as the config file is a nice help for other commands. If you really want to take awesome screenshots, I suggest you to read my guide about advanced techniques to create beautiful Battlefield 4 screenshots.
You might want to learn about some other useful BF4 console commands. I did put a list together with some useful commands. It might be that I will add some more console commands to the list in the future, if I did write an article about the other commands. Check the list out, it might be that there are other commands, you didn´t know.
Diary of Dennis 
Thanks for the commands! How would a person bind this to an extra mouse button as a toggled macro? For example, on Logitech mice you can program the buttons, but how would a person bind the ’tilde + UI.drawEnable 0′?
Hey. Sorry for the late reply. My videocard is damaged since yesterday and I had to get and install another one today. About your question… sorry I can´t help you at this point since I do not own a mouse with macro functions. But I like you idea as this would indeed simplify the way to show and hide the UI if you do video editing or something else. Hope you found the answer already on another place, so that you can go on with your intention.