2.13

package com.example.myapplication;

import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;

import android.annotation.SuppressLint;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import java.math.BigDecimal;
import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {

    private ListAdapter listAdapter;
    private String month11;
    private DBHelper helper;
    private  ListView listView;
    private List<costList>list;
    private TextView textView;
  @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Intent intent = getIntent();
        month11 = intent.getStringExtra("date");
        initView();
        initData();
      listView.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
          @Override
          public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
              new AlertDialog.Builder(MainActivity.this).setTitle("注意")
                      .setMessage("是否删除要此项记录?").setPositiveButton("确定", new DialogInterface.OnClickListener() {
                  public void onClick(DialogInterface dialog, int whichButton) {
                      String view1= String.valueOf(listAdapter.getItemId(position));
                      SQLiteDatabase db = helper.getWritableDatabase();
                      db.delete("account2","_id= ?",new String[]{view1});
                      Toast.makeText(getBaseContext(), "已删除", Toast.LENGTH_SHORT).show();
                      initData();
                  }
              }).setNegativeButton("取消", new DialogInterface.OnClickListener() {
                          public void onClick(DialogInterface dialog, int whichButton) {
                              Toast.makeText(getBaseContext(), "已取消删除", Toast.LENGTH_SHORT).show();
                          }
                      }).create().show();
              return false;
          }
      });
    }

    @SuppressLint("Range")
    private void initData() {
        list=new ArrayList<>();
        SQLiteDatabase db=helper.getReadableDatabase();
        Cursor cursor=db.query("account2",null,"Date like '"+month11+"%'",null,null,
                null,null);
        BigDecimal sum=new BigDecimal(0);
        while (cursor.moveToNext()){
            costList clist=new costList();//构造实例
            BigDecimal temp=new BigDecimal(cursor.getString(cursor.getColumnIndex("Money")));
            sum=sum.add(temp);
            clist.setSe(cursor.getString(cursor.getColumnIndex("Se")));
            clist.set_id(cursor.getString(cursor.getColumnIndex("_id")));
            clist.setTitle(cursor.getString(cursor.getColumnIndex("Title")));
            clist.setDate(cursor.getString(cursor.getColumnIndex("Date")));
            clist.setMoney(temp.toString());
            list.add(clist);
        }
        //绑定适配器
        listAdapter=new ListAdapter(this,list);
        listView.setAdapter(listAdapter);
        textView.setText(sum.toString());
        db.close();
    }
    private void initView() {
        helper=new DBHelper(MainActivity.this);
        listView = findViewById(R.id.list_view);
        textView =findViewById(R.id.t_money);
    }
}