Android_실습

ProductActivity

package com.example.ex0414;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.widget.ListView;

import java.util.ArrayList;

public class ProductActivity extends AppCompatActivity {
    ListView lvProduct;
    ProductAdapter adapter;
    ArrayList<ProductVO> list;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_product);
       
        lvProduct = findViewById(R.id.lv);
        list = new ArrayList<ProductVO>();
        //리스트 ID를 동적으로 접근하는 방법
        for(int i =0; i<11; i++){
            //리소스객체접근.리소스ID반환메소드(리소스ID, 리소스타입, 패키지명)
            int imgId = getResources().getIdentifier("item"+(i+1), "drawable",getPackageName());
            int strId = getResources().getIdentifier("item"+(i+1), "string",getPackageName());
            list.add(new ProductVO(imgId,strId,"10"));
      
        }

        adapter = new ProductAdapter(
                ProductActivity.this,
                R.layout.product_item,
                list);
        lvProduct.setAdapter(adapter);

    }
}

1. 리스트 ID를 동적으로 접근하려면 리소스 객체를 사용해야된다.
2. 형식으로는 getResources().getIndentifier(리소스아이디, 리소스 타입, 패키지명)이 들어가야 한다.

ProductAdapter

package com.example.ex0414;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.Toast;

import androidx.appcompat.app.AlertDialog;

import java.util.ArrayList;


public class ProductAdapter extends BaseAdapter {
    Context context;
    int item_layout;
    ArrayList<ProductVO> list;
    LayoutInflater inflater;
    public ProductAdapter(Context context, int item_layout, ArrayList<ProductVO> list) {
        this.context = context;
        this.item_layout = item_layout;
        this.list = list;
        this.inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }
    @Override
    public int getCount() {
        return list.size();
    }

    @Override
    //선택한 인덱스의 내용물?
    public Object getItem(int i) {
        return list.get(i);
    }

    @Override
    //선택한 인덱스를 반환하는 부분
    public long getItemId(int i) {
        return i;
    }

    @Override
    public View getView(int i, View view, ViewGroup viewGroup) {

        ItemHolder holder = null;

        if(view ==null){
            view = inflater.inflate(item_layout, viewGroup, false);
            holder = new ItemHolder(view);

            view.setTag(holder);
        }else{
            holder = (ItemHolder) view.getTag();
        }
        ProductVO vo = (ProductVO) getItem(i);
        holder.getImg().setImageResource(vo.getImg());
        holder.getPro_name().setText(vo.getName());
        holder.getPro_count().setText(vo.getProcount());

        holder.getBtn_product().setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                //대화상자 : AlertDialog
                AlertDialog.Builder builder = new AlertDialog.Builder(context);
                builder.setTitle("상품 보기").setMessage("상품개수 : "+vo.getProcount()).setPositiveButton("확인", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialogInterface, int i) {

                    }
                })
                .setNegativeButton("취소", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialogInterface, int i) {
                        dialogInterface.dismiss();
                    }
                });
                AlertDialog dialog = builder.create();
                dialog.show();

                Toast.makeText(context,vo.getName(),Toast.LENGTH_SHORT).show();


            }
        });

        return view; //젤 중요
    }
}

버튼의 클릭 시 알림 창이 뜰 수 있게 기능을 부여하였다.

ProductVO

package com.example.ex0414;

public class ProductVO {
    private int img;
    private int proname;
    private String procount;

    public ProductVO(){}

    public ProductVO(int img, int proname, String procount) {
        this.img = img;
        this.proname = proname;
        this.procount = procount;
    }

    public int getImg() {
        return img;
    }

    public void setImg(int img) {
        this.img = img;
    }

    public int getName() {
        return proname;
    }

    public void setName(int name) {
        this.proname = name;
    }

    public String getProcount() {
        return procount;
    }

    public void setProcount(String procount) {
        this.procount = procount;
    }

    @Override
    public String toString() {
        return "ProductVO{" +
                "img=" + img +
                ", proname='" + proname  +
                ", procount='" + procount  +
                '}';
    }
}

ItemHolder

package com.example.ex0414;

import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;

public class ItemHolder {
    private TextView pro_name;
    private TextView pro_count;
    private ImageView img;
    private Button btn_product;

    public ItemHolder(View itemView){
        img = itemView.findViewById(R.id.img);
        pro_name = itemView.findViewById(R.id.pro_name);
        pro_count = itemView.findViewById(R.id.pro_count);
        btn_product = itemView.findViewById(R.id.btn_product);
    }

    public ImageView getImg() { return img; }

    public TextView getPro_name() {
        return pro_name;
    }

    public TextView getPro_count() {
        return pro_count;
    }

    public Button getBtn_product() {
        return btn_product;
    }
}

product_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"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <ImageView
        android:id="@+id/img"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="16dp"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:srcCompat="@drawable/item1" />

    <TextView
        android:id="@+id/pro_name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="20dp"
        android:layout_marginTop="16dp"
        android:text="TextView"
        android:textSize="24sp"
        app:layout_constraintStart_toEndOf="@+id/img"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:id="@+id/pro_count"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="20dp"
        android:text="TextView"
        android:textSize="24sp"
        app:layout_constraintStart_toEndOf="@+id/img"
        app:layout_constraintTop_toBottomOf="@+id/pro_name" />

    <Button
        android:id="@+id/btn_product"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="24dp"
        android:layout_marginEnd="28dp"
        android:text="상품보기"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>

실행화면