安卓中RecyclerView的使用

1.创建一个主布局文件，里面只有FrameLayout，用于放置所要托管的活动:activity_main.xml:

xml version="1.0" encoding="utf-8"?>
<FrameLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:id="@+id/fragmentContainer"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  />

2.File->Project Structure->app->Dependencies->点击"+"号->Library Dependency->输入com.android.support:recyclerview-v7:25.0.1->确定
3.创建一个布局文件，里面有RecyclerView，用于显示可以回收的布局:fragment_reclclerview.xml

<android.support.v7.widget.RecyclerView
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent" />

4.添加在RecyclerView里面显示的列表项目文件:list_item.xml:

xml version="1.0" encoding="utf-8"?>
<Button xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/button"
    android:layout_width="match_parent"
    android:layout_height="120dp"
    tools:text="Sound name"/>

5.添加用于保存用户信息的类User.java:

package com.example.wanglunhui.recycleview;

/*
*存储用户信息的类
 */
public class User {

    private String mAddress;
    private String mAge;
    private String mSex;
    private String mName;

    public String getAddress() {
        return mAddress;
    }

    public void setAddress(String address) {
        mAddress = address;
    }

    public String getAge() {
        return mAge;
    }

    public void setAge(String age) {
        mAge = age;
    }

    public String getSex() {
        return mSex;
    }

    public void setSex(String sex) {
        mSex = sex;
    }

    public String getName() {
        return mName;
    }

    public void setName(String name) {
        mName = name;
    }
}

6.主文件:MainActivity.java:

public class MainActivity extends AppCompatActivity {//AppCompatActivity是Fragment子类，所以继承AppCompatActivity也是继承Frgment

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);//设置布局问Fragment布局，R.id.fragmentContainer在R.layout.activity_main中，所以先设置布局为它
        FragmentManager manager = getFragmentManager();
        Fragment fragment = manager.findFragmentById(R.id.fragmentContainer);//Fragment布局的id，用于显示托管的Activity

        if (fragment == null) {
            fragment = new MainFragment();
            manager.beginTransaction()
                    .add(R.id.fragmentContainer, fragment)//Fragment布局的id
                    .commit();
        }
    }

}

7.托管活动的文件MainFragment.java:

public class MainFragment extends Fragment {
    private List mUserList;//存储用户信息

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mUserList=new ArrayList<>();
        for (int i = 0; i < 30; i++) {//随机添加30个用户信息
            User user = new User();
            user.setAddress("Address" + i);
            user.setAge("Age" + i);
            user.setName("Name" + i);
            user.setSex("Sex" + i);
            mUserList.add(user);
        }
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        //显示的布局就为RecyclerView
        View view = inflater.inflate(R.layout.fragment_recyclerview, container, false);

        RecyclerView recyclerView = (RecyclerView)view//获取RecyclerView实例
                .findViewById(R.id.recycler_view);
        recyclerView.setLayoutManager(new GridLayoutManager(getActivity(), 3));//你想要控制其显示的方式，请通过布局管理器LayoutManager，这路设置成网格显示
        //recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));//这里设置成线性的显示
        recyclerView.setAdapter(new UserAdapter());

        return view;
    }

    private class UserHolder extends RecyclerView.ViewHolder {//用于托管每一个用于显示的单个项目，注意它继承自RecyclerView.ViewHolder
        private Button mButton;
        private User mUser;//每一个项目有一个按钮和对应的用户信息，所以有这两个属性

        public UserHolder(LayoutInflater inflater, ViewGroup parent) {
            super(inflater.inflate(R.layout.list_item, parent, false));//每一个项目在显示的时候都只是显示R.layout.list_item里面的按钮但实际上每一个按钮既有按钮，又有用户信息

            mButton = (Button)itemView.findViewById(R.id.button);//Button这个按钮实例

            mButton.setOnClickListener(new View.OnClickListener() {//设置布局管理器也是在Holder这里面设置的
                @Override
                public void onClick(View view) {
                    //因为Adapter的BindViewHolder将每一个User都绑定了，所以这里可以直接使用
                    Toast.makeText(getActivity(), "姓名:"+mUser.getName()+"年龄:"+mUser.getAge()+"性别:"+mUser.getSex()+"住址"+mUser.getAddress(), Toast.LENGTH_SHORT).show();
                }
            });
        }
    }

    private class UserAdapter extends RecyclerView.Adapter {//适配器，注意继承自RecyclerView.Adapter且内容为UserHolder

        @Override
        public UserHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
            LayoutInflater inflater = LayoutInflater.from(getActivity());
            return new UserHolder(inflater, viewGroup);
        }

        @Override
        public void onBindViewHolder(UserHolder soundHolder, int i) {//为每一个项目绑定对应的信息，对应每一个项目，参数UserHolder即为用于显示的每一个项目
            User user = mUserList.get(i);
            soundHolder.mUser=user;
            soundHolder.mButton.setText(user.getName());
        }

        @Override
        public int getItemCount() {//在RecycleView中显示的个数
            return mUserList.size();
        }
    }
}