寻物启事

Posted 2020-07-26 尚文韬

DBHelpter

 

package com.example.lenovo.heimingdan.com.hanqi.heimingdan.com;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

/**
 * Created by lenovo on 2016/6/7.
 */
public class DBHelper extends SQLiteOpenHelper {

    public DBHelper(Context context) {
        super(context,"blacklist.db", null,1);
    }
    @Override
    public void onCreate(SQLiteDatabase db) {

        String sql="CREATE TABLE t_blacklist ( " +
                "_id  INTEGER PRIMARY KEY " +
                "AUTOINCREMENT NOT NULL," +
                "phone_number VARCHAR(20) null)";
        db.execSQL(sql);//建表
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

    }


}

View Code

 

 

XunwuQS

package com.example.lenovo.xunwuqs.com.hanqi.xunwuqs;

/**
 * Created by lenovo on 2016/6/16.
 */
public class XunwuQS {
    private long id;
    private String name;

    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

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

    public XunwuQS(long id, String name) {
        this.id = id;
        this.name = name;
    }

    public XunwuQS(String name) {
        this.name = name;
    }
}

View Code

 

 

XunwuQSDAO

package com.example.lenovo.xunwuqs.com.hanqi.xunwuqs;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;


import java.util.ArrayList;

/**
 * Created by lenovo on 2016/6/16.
 */
public class XunwuQsDAO  {

    private DBHelper dbHelper;
    private String TABLE_NAME="main.NewTable";

    public XunwuQsDAO(Context context)
    {
        dbHelper=new DBHelper(context);
    }
    //增
    public long insert(XunwuQS xwqs)
    {
        long rtn=0;
        //连接数据库
        SQLiteDatabase sd=dbHelper.getReadableDatabase();
        //执行insert
        ContentValues cv=new ContentValues();
        cv.put("name",xwqs.getName());
        rtn=sd.insert(TABLE_NAME,null,cv);
        sd.close();
        return rtn;
    }
    //删
    public int delete(long id)
    {
        int rtn=0;
        SQLiteDatabase sd=dbHelper.getReadableDatabase();
        rtn=sd.delete(TABLE_NAME, "_id=?", new String[]{id + ""});
        sd.close();
        return rtn;
    }
    //改
    public int updete(XunwuQS xunwuQS)
    {
        int rtn=0;
        SQLiteDatabase sd=dbHelper.getWritableDatabase();
        ContentValues cv=new ContentValues();
        cv.put("name",xunwuQS.getName());
        rtn=sd.update(TABLE_NAME, cv, "_id=?", new String[]{xunwuQS.getId() + ""});
        sd.close();
        return rtn;
    }
    //查
    public ArrayList<XunwuQS> getAll()
    {
        ArrayList<XunwuQS> xunwuQSes=new ArrayList<>();
        SQLiteDatabase sd=dbHelper.getReadableDatabase();
        Cursor cursor=sd.query(TABLE_NAME,null,null,null,null,null,"_id desc");
        while (cursor.moveToNext())
        {
            XunwuQS xunwuQS=new XunwuQS(cursor.getLong(0),cursor.getString(1));
            xunwuQSes.add(xunwuQS);
        }
        cursor.close();
        sd.close();
        return xunwuQSes;
    }
}

View Code

 

 

Mainactivity

package com.example.lenovo.heimingdan;

import android.app.AlertDialog;
import android.content.DialogInterface;
import android.renderscript.ScriptGroup;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.InputType;
import android.view.ContextMenu;
import android.view.LayoutInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.CompoundButton;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import com.example.lenovo.heimingdan.com.hanqi.heimingdan.com.BlackListDAO;
import com.example.lenovo.heimingdan.com.hanqi.heimingdan.com.Heimingdan;

import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {

    ListView lv_1;
    //数据访问对象
    BlackListDAO bld=new BlackListDAO(this);
   //数据集合
    ArrayList<Heimingdan> alb;

    BLAdapter bla;

    //长按数据的索引
    int index;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        lv_1=(ListView)findViewById(R.id.lv_1);

        //增加上下文菜单,设置创建菜单的监听
        lv_1.setOnCreateContextMenuListener(this);
        //获取数据
        alb=bld.getAll();
        //显示数据
        //实例化adapter
        lv_1.setAdapter(new BLAdapter());
        bla=new BLAdapter();


    }

    //创建上下文菜单的重写方法
    @Override
    public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) {
        super.onCreateContextMenu(menu, v, menuInfo);
        menu.add(0, 1, 1, "修改");
        menu.add(0,2,2,"删除");
        //获取长按的适配器信息
        //1-得到菜单信息
        AdapterView.AdapterContextMenuInfo acmi=(AdapterView.AdapterContextMenuInfo)menuInfo;
        //2-得到数据的所在位置。acmi.position;
        index=acmi.position;

    }
    //相应菜单点击的回调方法
    @Override
    public boolean onContextItemSelected(MenuItem item) {

        switch (item.getItemId())
        {
            case 1:
                //修改
                final EditText editText = new EditText(this);
                editText.setText(alb.get(index).getPhonenumber());
                new AlertDialog.Builder(this)
                        .setTitle("修改黑名单")
                        .setView(editText)
                        .setNegativeButton("取消",null)
                        .setPositiveButton("确定", new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {
                                //1-得到新数据的实体类
                                //1）赋值；复制新的值再传递。值类型
                                // 2）传值；传递的是内存地址，指向同一对象。引用类型
                                Heimingdan bl = alb.get(index);
                                bl.setPhonenumber(editText.getText().toString());
                                //2-调用DAO的update()
                                if (bld.update(bl) > 0) {
                                    Toast.makeText(MainActivity.this, "修改成功", Toast.LENGTH_SHORT).show();
                                    //更新List
                                    //刷新列表
                                    bla.notifyDataSetChanged();
                                } else {
                                    Toast.makeText(MainActivity.this, "修改失败", Toast.LENGTH_SHORT).show();
                                }
                            }
                        })
                        .show();

                break;
            case 2:
                //添加一个删除-确定取消对话框
                //删除
                if (bld.delete(alb.get(index).getId())>0)
                {
                    new  AlertDialog.Builder(this)
                            .setTitle("确定删除？")
                            .setNegativeButton("取消", new DialogInterface.OnClickListener() {
                                @Override
                                public void onClick(DialogInterface dialog, int which) {
                                    Toast.makeText(MainActivity.this, "取消删除", Toast.LENGTH_SHORT).show();
                                }
                            })
                            .setPositiveButton("确定", new DialogInterface.OnClickListener() {
                                @Override
                                public void onClick(DialogInterface dialog, int which) {
                                    alb.remove(index);
                                    bla.notifyDataSetChanged();
                                    Toast.makeText(MainActivity.this, "删除成功", Toast.LENGTH_SHORT).show();

                                }
                            })
                            .show();
                }
                else
                {
                    Toast.makeText(MainActivity.this, "删除失败", Toast.LENGTH_SHORT).show();
                }
                break;
        }
        return super.onContextItemSelected(item);
    }

    //BaseAdapter的实现类
    class BLAdapter extends BaseAdapter
    {
        @Override
        public int getCount() {
            return alb.size();
        }

        @Override
        public Object getItem(int position) {
            return alb.get(position);
        }

        @Override
        public long getItemId(int position) {
            return alb.get(position).getId();
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            //得到数据
            Heimingdan bl= alb.get(position);
            //得到视图
            if (convertView==null)
            {
                //构建视图
                convertView=new TextView(MainActivity.this);
            }
            //视图和数据显示匹配
            TextView textView=(TextView)convertView;
            textView.setTextSize(20);
            textView.setHeight(80);
            textView.setText(bl.getPhonenumber());
            return textView;
        }
    }

    //添加按钮的监听器
    public void add_1(View v)
    {
        //添加
        final EditText editText = new EditText(this);
        editText.setHint("输入电话号码");
        editText.setInputType(InputType.TYPE_CLASS_PHONE);
        new AlertDialog.Builder(this)
                .setTitle("填加黑名单")
                .setView(editText)
                .setCancelable(false)
                .setNegativeButton("取消", null)
                .setPositiveButton("保存", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        //向数据库保存
                        //1-定义实体类
                        Heimingdan heimingdan = new Heimingdan(editText.getText().toString());
                        //2-通过DAO插入数据。调用insert
                        Long l =bld.insert(heimingdan);
                        if (l > 0) {
                            Toast.makeText(MainActivity.this, "保存成功", Toast.LENGTH_SHORT).show();
                            //更新List
                            //alb=bld.getAll();
                            heimingdan.setId(l);
                            alb.add(0,heimingdan);
                            //刷新列表
                            bla.notifyDataSetChanged();

                        } else {
                            Toast.makeText(MainActivity.this, "保存失败", Toast.LENGTH_SHORT).show();
                        }
                    }
                })
                .show();
    }
}

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