Animate 3 lines into arrow in iOS for a uibutton

Does anyone know how to animate 3 parallel lines to a right arrow as happens in navigation menu bar to open up a side menu by applying CGAfflineRotation to 3 views .

I really need help on these as so that at-least I can get an idea to start it.

This is what it will be look like some how tried to draw it:-

_______                  
_______                        \
_______         to   ___________\
                                /
                               /

Any idea or suggestion will be helpful.