How to change the icon when clicking the menu

[jkimkor]

In the normal state, an icon of "open" shape I hope that it will change to the "close" icon the moment you open it by clicking. What should I do?

PS. I would like to show the gray background behind the click, Is there a function independently?

[null1099]

see my working snippet for changing the icon here: https://github.com/Clans/FloatingActionButton/issues/430#issuecomment-374522726