如何在我的 android 工作室项目中找到根视图？

Question

我正在使用 android 工作室提供的导航菜单模板，我注意到主 activity 将内容视图设置为根视图，但我不确定哪个 XML 文件是什么？我假设它可能是 XML 视图，当我运行应用程序（将是 fragment_home.xml）时首先加载，但我不确定是否放置了任何特定代码在根视图的 xml 或 java 文件中？

这是主要代码 activity.java:

public class MainActivity extends AppCompatActivity {

    private AppBarConfiguration mAppBarConfiguration;
    private ActivityMainBinding binding;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        /*
        1. ON CREATE, SET MAIN SCREEN TO

        here instead of setting the main screen with findViewById, we are using BINDING!
        this is part of android jetpack!
         */
        binding = ActivityMainBinding.inflate(getLayoutInflater());  // inflate method creates an instance of the binding class for this activity to use
        setContentView(binding.getRoot());   // getRoot: a reference to the root view and passing it to setcontentview to make it the active view on the screen
                                             // when running the app, fragment_home shows up first. hence, this is the root view

        setSupportActionBar(binding.appBarMain.toolbar);
        binding.appBarMain.fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show();
            }
        });
        DrawerLayout drawer = binding.drawerLayout;
        NavigationView navigationView = binding.navView;

        // Passing each menu ID as a set of Ids because each menu should be considered as top level destinations.
        mAppBarConfiguration = new AppBarConfiguration.Builder(R.id.nav_home, R.id.nav_gallery, R.id.nav_slideshow)
                .setOpenableLayout(drawer)
                .build();
        NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment_content_main);
        NavigationUI.setupActionBarWithNavController(this, navController, mAppBarConfiguration);
        NavigationUI.setupWithNavController(navigationView, navController);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onSupportNavigateUp() {
        NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment_content_main);
        return NavigationUI.navigateUp(navController, mAppBarConfiguration)
                || super.onSupportNavigateUp();
    }
}

和项目结构的图片：

Answer 1

activity_main.xml

ActivityMainBinding 由 viewbinding/databinding 生成，如果您 cmd/ctrl 单击它，它将带您到 activity_main.xml

如何在我的 android 工作室项目中找到根视图？

how do i find the root view in my android studio project?

android

rootview

android-studio

navigation-drawer

setcontentview