java - getActionBar().setSelectedNavigationItem(position); -


i had nullpointerexception when used method above, instead of getsupportactionbar().setselectednavigationitem(position);

for future reference, how can android studio or intellijidea give me better tip on mistake. havent tried analyze -> inspect code

i received common mistake commonsguy sample demos.

it available in google's own effectivenavigation code sample as:

// set action bar. final actionbar actionbar = getactionbar();

here, actionbar stayed null , set 

if(actionbar != null)

statements , code managed run, until changed android support library method: getsupportactionbar()

this example google had managed run without showing me 3 "sections tabs"

your activity should extending appcompatactivity make possible use getsupportactionbar() method. please check if activity's theme not extending noactionbar.


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