private Toolbar toolbar;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
toolbar = (Toolbar) findViewById(R.id.my_toolbar);
*// here is where you set it to show on the toolbar*
setSupportActionBar(toolbar);
}
Well, you need to set support action bar setSupportActionBar(); and pass your variable, like so: setSupportActionBar(toolbar);