가계부 관련 앱에서 삭제 버튼을 만들려고 하는데요

Question

package com.androidtown.yuproject;

import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.TextUtils;
import android.util.Log;
import android.view.View;
import android.view.inputmethod.InputMethodManager;
import android.widget.AdapterView;
import android.widget.EditText;
import android.widget.ImageButton;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import org.androidtown.mycalendar.R;

import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import java.util.Locale;

public class MainActivity extends AppCompatActivity {

    private static final String TAG = "MainActivity";
    private TextView thedate;
    private ImageButton btn_go_calendar;
    private TextView sum_view;


    MyDBTable mHelper;
    SQLiteDatabase db;
    Cursor cursor;
    MyAdapter myAdapter;

    final static String KEY_ID = "_id";
    final static String KEY_CONTEXT = "context";
    final static String KEY_PRICE = "price";
    final static String TABLE_NAME = "MyAccountList";
    final static String KEY_DATE = "date";
    public static String View_DATE = getToday_date();

    public int a;

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

        setTitle("지출 내역");

        //데이터베이스 생성
        mHelper = new MyDBTable(this);
        db = mHelper.getWritableDatabase();

        //레이아웃 변수설정
    //    thedate = (TextView) findViewById(R.id.date);
    //    btn_go_calendar = (ImageButton) findViewById(R.id.btn_go_calendar);
        ListView list = (ListView) findViewById(R.id.account_list);
        sum_view = (TextView) findViewById(R.id.total_sum);

        //날짜 표시 인텐트 설정
        Intent comingIntent = getIntent();
        Log.d(TAG, "getintent OK");
        String date = comingIntent.getStringExtra("date");
        if (!TextUtils.isEmpty(date)) {
            View_DATE = date;
            thedate.setText(date);
            Log.d(TAG, "string is not empty");
        } else {
         //   date = getToday_date();
          thedate.setText(View_DATE);
        }

        // 총합 가격 표시
        String queryPriceSum = String.format(" SELECT SUM(price) FROM %s WHERE date = '%s'", TABLE_NAME, View_DATE);
        cursor = db.rawQuery(queryPriceSum, null);
        cursor.moveToNext();
        String sum = String.valueOf(cursor.getInt(0));
        Log.d(TAG, "sum : " + sum);
        sum_view.setText(sum);

        //달력 이동
        btn_go_calendar.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent intent = new Intent(MainActivity.this, CalendarActivity.class);
                startActivity(intent);

            }
        });

        //커서 어댑터 생성
        String querySelectAll = String.format("SELECT * FROM %s WHERE date = '%s'", TABLE_NAME, View_DATE);
        cursor = db.rawQuery(querySelectAll, null);
        myAdapter = new MyAdapter(this, cursor);

        //리스트뷰 어댑터 설정
        list.setAdapter(myAdapter);



    }

  

    public void OnClick_delbutton(View view) {
    /*    */

    }

    public void OnClick_addButton(View v) {
        EditText eContext = (EditText) findViewById(R.id.edit_context);
        EditText ePrice = (EditText) findViewById(R.id.edit_price);

        String contexts = eContext.getText().toString();
        int price = Integer.parseInt(ePrice.getText().toString());
        String today_Date = getToday_date();
        Log.d(TAG, "값 확인" + contexts + ", " + price + ", " + today_Date);


        String query = String.format(
                "INSERT INTO %s VALUES ( null, '%s', %d, '%s' );", TABLE_NAME, contexts, price, View_DATE);
        db.execSQL(query);

        // 총합 가격 표시
        String queryPriceSum = String.format(" SELECT SUM(price) FROM %s WHERE date = '%s'", TABLE_NAME, View_DATE);
        cursor = db.rawQuery(queryPriceSum, null);
        cursor.moveToNext();
        String sum = String.valueOf(cursor.getInt(0));
        Log.d(TAG, "sum : " + sum);
        sum_view.setText(sum);

        //리스트 갱신
        String querySelectAll = String.format("SELECT * FROM %s WHERE date = '%s'", TABLE_NAME, View_DATE);
        cursor = db.rawQuery(querySelectAll, null);
        myAdapter.changeCursor(cursor);

        eContext.setText("");
        ePrice.setText("");

        // 저장 버튼 누른 후 키보드 안보이게 하기
        InputMethodManager imm =
                (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
        imm.hideSoftInputFromWindow(ePrice.getWindowToken(), 0);
    }


    static public String getToday_date() {
        SimpleDateFormat mSimpleDateFormat = new SimpleDateFormat("yyyy년M월d일", Locale.KOREA);
        Date currentTime = new Date();
        String Today_day = mSimpleDateFormat.format(currentTime).toString();
        return Today_day;
    }

}

중앙에 주석 철리 한 delbutton에 어떻게 넣어야...listview에서도 사라지고 db도 사라질까요 ㅜㅜ 

입니다..ㅜㅜ