Android E/RecyclerView：未连接适配器；跳过布局（MainActivity到HomeFragment）

如何将这些活动从MainActivity移动到HomeFragment？ 我可以通过在主片段中创建新类来移动吗

我试图通过创建新类

HomeFragment2

移动，如下所示

package com.domachita.jsdict.ui.home;

import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.RecyclerView;
import android.text.Editable;
import android.text.TextWatcher;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import android.support.annotation.Nullable;
import android.support.annotation.NonNull;
import android.support.v4.app.Fragment;
import android.arch.lifecycle.Observer;
import android.arch.lifecycle.ViewModelProviders;

import com.domachita.jsdict.Adapter.SearchAdapter;
import com.domachita.jsdict.Database.Database;
import com.domachita.jsdict.R;
import com.mancj.materialsearchbar.MaterialSearchBar;

import java.util.ArrayList;
import java.util.List;

public class HomeFragment extends Fragment{

    private HomeViewModel homeViewModel;

    @Override
    public View onCreateView(LayoutInflater inflater,
                             ViewGroup container, Bundle savedInstanceState) {
        homeViewModel =
                ViewModelProviders.of(this).get(HomeViewModel.class);
        View root = inflater.inflate(R.layout.fragment_home, container, false);
        final TextView textView = root.findViewById(R.id.text_home);
        homeViewModel.getText().observe(this, new Observer<String>() {
            @Override
            public void onChanged(@Nullable String s) {
                textView.setText(s);
            }
        });
        return root;
    }
}

class HomeFragment2 extends AppCompatActivity {


    RecyclerView recyclerView;
    RecyclerView.LayoutManager layoutManager;
    SearchAdapter adapter;

    MaterialSearchBar materialSearchBar;
    List<String> suggestList = new ArrayList<>();

    Database database;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        //init view
        recyclerView = (RecyclerView)findViewById(R.id.recycler_search);
        layoutManager = new LinearLayoutManager(this);
        recyclerView.setLayoutManager(layoutManager);
        recyclerView.setHasFixedSize(true);

        materialSearchBar = (MaterialSearchBar)findViewById(R.id.search_bar);

        //init DB
        database = new Database(this);

        //Setup search bar
        materialSearchBar.setHint("検索したい語句を入力");

        materialSearchBar.addTextChangeListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {

            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {

                List<String> suggest = new ArrayList<>();
                for (String search:suggestList)
                {
                    if (search.toLowerCase().contains(materialSearchBar.getText().toLowerCase()))
                        suggest.add(search);
                }
                materialSearchBar.setLastSuggestions(suggest);

            }

            @Override
            public void afterTextChanged(Editable s) {

            }
        });
        materialSearchBar.setOnSearchActionListener(new MaterialSearchBar.OnSearchActionListener() {
            @Override
            public void onSearchStateChanged(boolean enabled) {
                if (enabled)
                    recyclerView.setAdapter(adapter);
            }

            @Override
            public void onSearchConfirmed(CharSequence text) {
                startSearch(text.toString());
            }

            @Override
            public void onButtonClicked(int buttonCode) {

            }
        });


        //Init Adapter default set all result
        adapter = new SearchAdapter(this,database.getDicts());
        recyclerView.setAdapter(adapter);

    }

    private void startSearch(String text) {

        adapter = new SearchAdapter(this,database.getDictByJapanese(text));
        recyclerView.setAdapter(adapter);
    }


}

我修改了很多，但无法解决这个问题

---

提前谢谢

在oncreate（）中或方法上方添加此行：

   adapter = new SearchAdapter(this,database.getDicts());
    recyclerView.setAdapter(adapter)

---

我认为发生的事情是，您正在主线程上运行

数据库.getDicts（）

，一旦得到结果，您就可以设置适配器。尝试检查

数据库.getDicts（）

占用的时间

---

从DB获取数据的最佳方法是异步执行。

什么数据库

database.getDicts（）

return？你能加上这个吗？我已经用数据库代码更新了我的问题。谢谢你的回答，但仍然没有显示列表。

   adapter = new SearchAdapter(this,database.getDicts());
    recyclerView.setAdapter(adapter)