twNavBarName = (TextView) findViewById(R.id.nav_header_tw_name);
twNavBarEmail = (TextView) findViewById(R.id.nav_header_tw_email);
twNavBarName.setText("fdfs");
NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
...
View navHeader = navigationView.getHeaderView(0);
TextView twNavBarName = (TextView) navHeader.findViewById(R.id.nav_header_tw_name);
twNavBarName.setText("automatik");