为什么我要继续出现错误:e/recyclerview:没有附加适配器;跳过布局

Question

我正在为我的A-levels处理app，而app加载良好时，我的数据都没有出现。当我检查调试代码时，我会收到此错误：

e/recyclerview：无适配器；跳过布局

我是Android Studio的新手，所以我不知道该放在哪里适配器。

public class Home extends AppCompatActivity
    implements NavigationView.OnNavigationItemSelectedListener {
FirebaseDatabase database;
DatabaseReference Category;
TextView txtFullName;
RecyclerView recycler_menu;
RecyclerView.LayoutManager layoutManager;
FirebaseRecyclerAdapter<Category, MakeupViewHolder> adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_home);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    toolbar.setTitle("Makeup");
    setSupportActionBar(toolbar);
    //Init Firebase
    database = FirebaseDatabase.getInstance();
    Category = database.getReference("Category");
    FloatingActionButton fab = (FloatingActionButton)findViewById(R.id.fab);
    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 = (DrawerLayout) findViewById(R.id.drawer_layout);
    ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
            this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
    drawer.setDrawerListener(toggle);
    toggle.syncState();
    NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
    navigationView.setNavigationItemSelectedListener(this);
    //Set Name for user
    View headerView = navigationView.getHeaderView(0);
    txtFullName = (TextView)headerView.findViewById(R.id.txtFullName);
    txtFullName.setText(Common.currentUser.getName());
    //Load menu
    recycler_menu = (RecyclerView)findViewById(R.id.recycler_menu);
    recycler_menu.setHasFixedSize(true);
    layoutManager = new LinearLayoutManager(this);
    recycler_menu.setLayoutManager(layoutManager);
    recycler_menu.setAdapter(adapter);
    loadMenu();
}

Answer 1

我不认为这是您需要处理的错误。我不知道为什么Android团队选择将该日志标记为"错误"。

一种称为dispatchlayout的方法作为布局阶段的一部分，如果 LayoutManager或 Adapter是 null，则该方法基本上不做任何事情。这是有道理的，并且在这些情况下打印了该日志。

当您将LayoutManager和Adapter同时设置为RecyclerView