android - Open fragment from another fragment -

i´m building android application , trying default navigation android studio generates scratch.

how should open new fragment inside fragment?

replace fragment b fragment a:

fragmentmanager fragmentmanager = getactivity().getfragmentmanager(); fragmenttransaction fragmenttransaction = fragmentmanager.begintransaction(); fragmenttransaction.replace(r.id.frame_layout_container, new fragmentb()); fragmenttransaction.addtobackstack(null); fragmenttransaction.commit(); 

done