package Ġcom . example . bit co int icker app . view Ċ Ċ import Ġandroidx . appcompat . app . AppCompatActivity Ċ import Ġandroid . os . Bundle Ċ import Ġandroid . view . Menu Ċ import Ġandroidx . appcompat . widget . Search View Ċ import Ġandroidx . databinding . Data Binding Util Ċ import Ġandroidx . navigation . fragment . Nav Host Fragment Ċ import Ġcom . example . bit co int icker app . R Ċ import Ġcom . example . bit co int icker app . databinding . Activity Main Binding Ċ Ċ class ĠMainActivity Ġ: ĠAppCompatActivity () Ġ{ ĊĊĠĠĠ Ġprivate Ġlateinit Ġvar Ġbinding Ġ: ĠActivity Main Binding ĊĊĠĠĠ Ġoverride Ġfun ĠonCreate ( savedInstanceState : ĠBundle ?) Ġ{ ĊĠĠĠĠĠĠĠ Ġsuper . onCreate ( savedInstanceState ) ĊĠĠĠĠĠĠĠ Ġbinding Ġ= ĠData Binding Util . set ContentView ( this , R . layout . activity _ main ) ĊĊĠĠĠĠĠĠĠ Ġval Ġnav Host Fragment Ġ= ĊĠĠĠĠĠĠĠĠĠĠĠ Ġsupport FragmentManager . find Fragment ById ( R . id . fragment ) Ġas ĠNav Host Fragment ĊĠĠĠĠĠĠĠ Ġval Ġnav Controller Ġ= Ġnav Host Fragment . nav Controller ĊĊĊĠĠĠĠĠĠĠ Ġ// Firebase ĠLogin ĠScreen , ĠMain ĠScreen , ĠDetail ĠScreen , ĠF avorite ĠScreen ĊĊĊĊ ĊĊĠĠĠ Ġ} ĊĊĊ Ċ }