Unable to set main fab Image dynamically

[ksaittis]

I would like to be able to change the main fab image dynamically according to what is currently selected from the menu. Currently the only methods provided by the FabSpeedDial type do not support to dynamically change the image of the main fab. The methods setBackground and setForeground do not meet the behaviour i expect from the main fab icon. I would like to be able to modify the main fab icon the same way the app:fabDrawable="@drawable/ic_list" attribute does. I was unable to do through the code thus i was unable to replicate the behaviour of .setImageResource method from the FloatingActionButton type