RecyclerView 구현

RecyclerView

 

1. RecyclerViewItem.java

public class RecyclerViewItem {
    private String mImgName;
    private String mMainText;
    private String mSubText;

    public String getImgName() {
        return mImgName;
    }

    public void setImgName(String imgName) {
        this.mImgName = imgName;
    }

    public String getMainText() {
        return mMainText;
    }

    public void setMainText(String mainText) {
        this.mMainText = mainText;
    }

    public String getSubText() {
        return mSubText;
    }

    public void setSubText(String subText) {
        this.mSubText = subText;
    }
}

리스트 뷰에 나타낼 아이템 모델을 생성한다.

 

 

2. recycler_view_item.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginStart="15dp"
    android:layout_marginEnd="15dp">

    <ImageView
        android:id="@+id/imgView_item"
        android:layout_width="100dp"
        android:layout_height="100dp"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:id="@+id/txt_main"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="20sp"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toBottomOf="@id/imgView_item" />

    <TextView
        android:id="@+id/txt_sub"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="15sp"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toBottomOf="@id/txt_main" />

</androidx.constraintlayout.widget.ConstraintLayout>

item 레이아웃을 꾸며준다.

 

3. MyRecyclerViewAdapter.java

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;

import com.taek.test.R;
import com.taek.test.databinding.RecyclerViewItemBinding;

import java.util.List;

public class MyRecyclerViewAdapter extends RecyclerView.Adapter<MyRecyclerViewAdapter.MyViewHolder> {

    private List<RecyclerViewItem> list;
    private Context context;

    public MyRecyclerViewAdapter(List<RecyclerViewItem> list, Context context) {
        this.list = list;
        this.context = context;
    }

    @NonNull
    @Override
    public MyViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View itemView = LayoutInflater.from(context).inflate(R.layout.recycler_view_item, parent, false);
        return new MyViewHolder(itemView);
    }

    @Override
    public void onBindViewHolder(@NonNull MyViewHolder holder, int position) {
        holder.bindItem(list.get(position));
    }

    @Override
    public int getItemCount() {
        return list.size();
    }

    class MyViewHolder extends RecyclerView.ViewHolder {
        RecyclerViewItemBinding binding;

        public MyViewHolder(@NonNull View itemView) {
            super(itemView);
            binding = RecyclerViewItemBinding.bind(itemView);
        }

        void bindItem(RecyclerViewItem item) {
            binding.imgViewItem.setImageResource(R.drawable.ic_launcher_background);
            binding.txtMain.setText(item.getMainText());
            binding.txtSub.setText(item.getSubText());
        }
    }
}

Adapter 생성

 

 

4. activity_recycler_view.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".list.RecyclerViewActivity">

    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/recyclerView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_margin="20dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</androidx.constraintlayout.widget.ConstraintLayout>

recyclerView 액티비티 레이아웃

 

5. RecyclerViewActivity.java

import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.LinearLayoutManager;

import android.os.Bundle;

import com.taek.test.databinding.ActivityRecyclerViewBinding;

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

public class RecyclerViewActivity extends AppCompatActivity {

    private ActivityRecyclerViewBinding binding;
    private List<RecyclerViewItem> list;
    private MyRecyclerViewAdapter adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        binding = ActivityRecyclerViewBinding.inflate(getLayoutInflater());
        setContentView(binding.getRoot());

        list = new ArrayList<>();

        for (int i = 0; i < 10; i++) {
            addItem("iconName", "Taek" + i, "taek2.tistory.com");
        }

        adapter = new MyRecyclerViewAdapter(list, this);

        binding.recyclerView.setAdapter(adapter);
        binding.recyclerView.setLayoutManager(new LinearLayoutManager(this));
    }

    private void addItem(String imgName, String mainText, String subText) {
        RecyclerViewItem item = new RecyclerViewItem();

        item.setImgName(imgName);
        item.setMainText(mainText);
        item.setSubText(subText);

        list.add(item);
    }
}

 

 

 

 

LifeCycle 신경 안쓰고 onCreate 메서드에 다 넣었다.

개발할 때는 LifeCycle 고려해서 하도록 합시다.