recyclerView Ex2

// ItemData.java
import java.util.HashMap;
import java.util.Map;

public class ItemData {
    private String image; //int to String
    private String title;
    private String contents;

    public ItemData() { } // 기본생성자

    public ItemData(String image, String title, String contents) {
        this.image = image; //int to String
        this.title = title;
        this.contents = contents;
    }

    public String getImage() {
        return image;
    }

    public void setImage(String image) {
        this.image = image;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getContents() {
        return contents;
    }
    public void setContents(String contents) {
        this.contents = contents;
    }

    // 새로추가됨
    public Map<String, Object> toMap(){
        HashMap<String, Object> result = new HashMap<>();
        result.put("image", image);
        result.put("title", title);
        result.put("contents", contents);
        return result;
    }
    //새로추가됨 끝
}

 

build.gradle 에 추가

    implementation 'com.github.bumptech.glide:glide:4.10.0'
    annotationProcessor 'com.github.bumptech.glide:compiler:4.10.0'

MyRecyclerAdapter.java

public class MyRecyclerAdapter  extends  RecyclerView.Adapter<MyRecyclerAdapter.ViewHolder>{

    private ArrayList<ItemData> itemData;

    //생성자
    public MyRecyclerAdapter(ArrayList<ItemData> itemData) {
        this.itemData = itemData;
    }

    // 이벤트 처리 인터페이스 생성
    public interface MyRecyclerViewClickListener{
        void onItemClicked(int position);
        void onItemLongClicked(int position);
        void onTitleClicked(int position);
        void onContentsClicked(int position);
        void onImageViewClicked(int position);
    }
    private MyRecyclerViewClickListener mListener;
    public void setOnClickListener(MyRecyclerViewClickListener listener){
        this.mListener = listener;
    }


    public class ViewHolder extends RecyclerView.ViewHolder {
        TextView title;
        TextView contents;
        ImageView imageView;
        public ViewHolder(@NonNull View itemView) {
            super(itemView);
            title = itemView.findViewById(R.id.title_text);
            contents = itemView.findViewById(R.id.contents_text);
            imageView = itemView.findViewById(R.id.imageView);
            imageView.setBackground(new ShapeDrawable(new OvalShape()));
            imageView.setClipToOutline(true);

        }
    }

    @NonNull
    @Override
    public MyRecyclerAdapter.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext())
                .inflate(R.layout.list_item, parent, false);
        ViewHolder holder = new ViewHolder(view);
        return holder;
    }

    @Override
    public void onBindViewHolder(@NonNull final MyRecyclerAdapter.ViewHolder holder, int position) {
        ItemData item = itemData.get(position);
        holder.title.setText(item.getTitle());
        holder.contents.setText(item.getContents());
        //holder.imageView.setImageResource(item.getImage());
        Glide.with(holder.itemView)
                .load(item.getImage())
                .into(holder.imageView);

        // 이벤트 처리 관련 리스너 처리
        if(mListener != null){
            final  int pos = position;
            holder.itemView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    mListener.onItemClicked(pos);
                }
            });
            holder.itemView.setOnLongClickListener(new View.OnLongClickListener() {
                @Override
                public boolean onLongClick(View v) {
                    mListener.onItemLongClicked(holder.getAdapterPosition());
//                    remove(holder.getAdapterPosition());
                    return true;
                }
            });
            holder.title.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    mListener.onTitleClicked(holder.getAdapterPosition());
                }
            });
            holder.contents.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    mListener.onContentsClicked(holder.getAdapterPosition());
                }
            });
            holder.imageView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    mListener.onImageViewClicked(pos);
                }
            });
        }
    }

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

    public void remove(int position){
        try {
            itemData.remove(position);
            notifyDataSetChanged();
        } catch (IndexOutOfBoundsException e){
            e.printStackTrace();
        }
    }
}

MainActivity.java

 

import android.app.Dialog;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Toast;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;

import com.google.firebase.database.DataSnapshot;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.Query;
import com.google.firebase.database.ValueEventListener;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;


public class MainActivity extends AppCompatActivity implements MyRecyclerAdapter.MyRecyclerViewClickListener {

    private RecyclerView recyclerView;
    private RecyclerView.LayoutManager layoutManager;
    private ArrayList<ItemData> dataList;
    private FirebaseDatabase database;
    private DatabaseReference databaseReference;
    private MyRecyclerAdapter adapter;

    String IMAGE_URL="https://firebasestorage.googleapis.com/v0/b/recyclerviewex-b819d.appspot.com/o/pic_013.jpg?alt=media&token=611fca00-4b2d-497f-86df-7d9ce2a8a2be";
    static int i=0;

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

        recyclerView = findViewById(R.id.recyclerView);
        recyclerView.setHasFixedSize(true); //리사이클러뷰 성능강화
        layoutManager = new LinearLayoutManager(this);
        recyclerView.setLayoutManager(layoutManager);
        dataList = new ArrayList<>();

        database = FirebaseDatabase.getInstance(); // 파이어베이스 데이터베이스 연동
        databaseReference = database.getReference("CAT"); //DB 테이블 연결

        databaseReference.addListenerForSingleValueEvent(new ValueEventListener() {
            @Override
            public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
                //파이어 베이스 데이터베이스에 데이터를 받아오는곳
                dataList.clear(); //기존 배열 리스트가 존재하지 않게 초기화
                for(DataSnapshot snapshot : dataSnapshot.getChildren()){ //반복문으로 데이터List 추출
                    ItemData itemData = snapshot.getValue(ItemData.class); // 만들어둔 ItemData 객체에 데이터를 담는다.
                    dataList.add(itemData); // 담은 데이터를 배열리스트에 넣고 리사이클러 뷰로 보냄
                }
                adapter.notifyDataSetChanged(); //리스트 저장 및 새로 고침
            }

            @Override
            public void onCancelled(@NonNull DatabaseError databaseError) {
                Log.e("MainActivity", String.valueOf(databaseError.toException()));
            }
        });
        adapter = new MyRecyclerAdapter(dataList);
        recyclerView.setAdapter(adapter);

        Button button_add = findViewById(R.id.button_add);
        button_add.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String title = "CAT"+Integer.toString(i);
                String contents = "예쁨";
                if(!IsExistTITLE(title)){
                    postItemData(true, title, contents);
                    getFirebaseDatabase();
                }else{
                    Toast.makeText(getApplicationContext(), "이미 존재하는 ID 입니다. 다른 ID로 설정해주세요.",
                            Toast.LENGTH_LONG).show();
                }



            }
        });
        adapter.setOnClickListener(this);

    }

    @Override
    public void onItemClicked(int position) {
        Toast.makeText(getApplicationContext(),""+position, Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onTitleClicked(int position) {
        Toast.makeText(getApplicationContext(),""+dataList.get(position).getTitle(), Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onContentsClicked(int position) {
        Toast.makeText(getApplicationContext(),""+dataList.get(position).getContents(), Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onImageViewClicked(int position) {
        Toast.makeText(getApplicationContext(),""+dataList.get(position).getImage(),Toast.LENGTH_SHORT).show();
   }

    @Override
    public void onItemLongClicked(int position) {
        adapter.remove(position);
        Toast.makeText(getApplicationContext(),
                dataList.get(position).getTitle()+" is removed",Toast.LENGTH_SHORT).show();
    }

    public void onMenuInsert(View view) {
//        final View innerView = getLayoutInflater().inflate(R.layout.list_insert,null);
        final Dialog mDialog = new Dialog(this);
        mDialog.setTitle("Title");
        mDialog.setContentView(R.layout.list_insert);
        mDialog.setCancelable(true);

//        //DialogSize조절
        WindowManager.LayoutParams params = mDialog.getWindow().getAttributes();
        params.width = WindowManager.LayoutParams.MATCH_PARENT;
//        params.height = WindowManager.LayoutParams.MATCH_PARENT;
        mDialog.getWindow().setAttributes((android.view.WindowManager.LayoutParams) params);


        final EditText contents_edittext = mDialog.findViewById(R.id.contents_edittext);
        final EditText title_edittext = mDialog.findViewById(R.id.title_edittext);
        ImageView imageView_insert = mDialog.findViewById(R.id.imageView_insert);
        Button button_go = mDialog.findViewById(R.id.button_go);
        Button button_cancel = mDialog.findViewById(R.id.button_cancel);

        button_go.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String mMenuTitle = title_edittext.getText().toString();
                String mMenuContents = contents_edittext.getText().toString();
//                dataList.add(new ItemData(IMAGE_URL, mMenuTitle, mMenuContents));

                postItemData(true, "CAT"+mMenuTitle, mMenuContents);
                getFirebaseDatabase();

                mDialog.dismiss();
            }
        });
        button_cancel.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                mDialog.dismiss();
            }
        });
        i = (i+1)%35;
        mDialog.show();
        adapter.notifyDataSetChanged();
    }

    public void postItemData(boolean add, String title, String content){
        databaseReference = FirebaseDatabase.getInstance().getReference();
        Map<String, Object> childUpdates = new HashMap<>();
        Map<String, Object> postValues = null;
        IMAGE_URL = "https://firebasestorage.googleapis.com/v0/b/recyclerviewex-b819d.appspot.com/o/pic_013.jpg?alt=media&token=611fca00-4b2d-497f-86df-7d9ce2a8a2be";
//        TITLE = "CAT"+Integer.toString(i);
//        CONTENTS = "예쁨";
        if(add){
            ItemData itemData = new ItemData(IMAGE_URL, title, content);
            postValues = itemData.toMap();
        }
        childUpdates.put("/CAT/" + title, postValues);
        databaseReference.updateChildren(childUpdates);
        i++;
    }

    public void getFirebaseDatabase(){
        ValueEventListener postListener = new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {
                dataList.clear(); //기존 배열 리스트가 존재하지 않게 초기화
                for(DataSnapshot snapshot : dataSnapshot.getChildren()){ //반복문으로 데이터List 추출
                    ItemData itemData = snapshot.getValue(ItemData.class); // 만들어둔 ItemData 객체에 데이터를 담는다.
                    dataList.add(itemData); // 담은 데이터를 배열리스트에 넣고 리사이클러 뷰로 보냄
                }
                adapter.notifyDataSetChanged(); //리스트 저장 및 새로 고침
            }

            @Override
            public void onCancelled(DatabaseError databaseError) {
                Log.w("getFirebaseDatabase","loadPost:onCancelled", databaseError.toException());
            }
        };
    }

    public boolean IsExistTITLE(String title){
        boolean IsExist = dataList.contains(title);
        return IsExist;
    }
    public String setTextLength(String text, int length){
        if(text.length()<length){
            int gap = length - text.length();
            for (int i=0; i<gap; i++){
                text = text + " ";
            }
        }
        return text;
    }
}