andorid 练习之黑名单

时间：2021-12-07 22:43:35

activity_mian.xml

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:paddingBottom="@dimen/activity_vertical_margin"

    android:paddingLeft="@dimen/activity_horizontal_margin"

    android:paddingRight="@dimen/activity_horizontal_margin"

    android:paddingTop="@dimen/activity_vertical_margin"

    tools:context="com.hanqi.blacklist.MianActivity"

    android:orientation="vertical">

    <ListView

        android:layout_width="match_parent"

        android:layout_height="0dp"

        android:layout_weight="1"

        android:id="@android:id/list"

        >

    </ListView>

    <TextView

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:id="@android:id/empty"

        android:layout_weight="1"

        android:gravity="center"

        android:text="还没有一个黑名单"/>

    <Button

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="添加"

        android:onClick="bt1_onclick"/>

</LinearLayout>

DBHelper.java

package com.hanqi.blacklist;

import android.content.Context;

import android.database.sqlite.SQLiteDatabase;

import android.database.sqlite.SQLiteOpenHelper;

import android.util.Log;

/**

 * Created by Administrator on 2016/4/15.

 */

public class DBHelper extends SQLiteOpenHelper {

    public DBHelper(Context context) {

        super(context,"blacklist.db", null, 1);

    }

    @Override

    public void onCreate(SQLiteDatabase db) {

        db.execSQL("create table black_number (_id integer primary key autoincrement, phone_nubmer varchar)");

        Log.e("TAG","onCreate");

    }

    @Override

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

    }

}

BlackNumber.java

package com.hanqi.blacklist;

/**

 * Created by Administrator on 2016/4/15.

 */

public class BlackNumber  {

    private long id;

    private String phonenumber;

    public long getId() {

        return id;

    }

    public void setId(long id) {

        this.id = id;

    }

    public String getPhonenumber() {

        return phonenumber;

    }

    public void setPhonenumber(String phonenumber) {

        this.phonenumber = phonenumber;

    }

    public BlackNumber() {

    }

    public BlackNumber(long id, String phonenumber) {

        this.id = id;

        this.phonenumber = phonenumber;

    }

    public BlackNumber(String phonenumber) {

        this.phonenumber = phonenumber;

    }

    @Override

    public String toString() {

        return "BlackNumber{" +

                "id=" + id +

                ", phonenumber='" + phonenumber + '\'' +

                '}';

    }

}

BlackNumberDAO.java

package com.hanqi.blacklist;

import android.content.ContentValues;

import android.content.Context;

import android.database.Cursor;

import android.database.sqlite.SQLiteDatabase;

import android.util.Log;

import java.util.ArrayList;

import java.util.List;

/**

 * Created by Administrator on 2016/4/15.

 */

public class BlackNumberDAO {

    private DBHelper dbHelper;

    //初始化工具类

    public BlackNumberDAO(Context context)

    {

        dbHelper = new DBHelper(context);

    }

    //增

    public void insert(BlackNumber blackNumber)

    {

        //获取数据库连接

        SQLiteDatabase sql = dbHelper.getWritableDatabase();

        //要添加数据的键值对集合

        ContentValues contentValues =new ContentValues();

        contentValues.put("phone_number",blackNumber.getPhonenumber());

        //数据添加

        sql.insert("black_number",null,contentValues);

        //关闭数据库

        sql.close();

        Log.e("TAG","添加数据成功");

    }

    //删除

    public void delete(long id)

    {

        //获取数据库连接

        SQLiteDatabase sql = dbHelper.getWritableDatabase();

        //数据删除

        sql.delete("black_number","_id=?",new String[]{String.valueOf(id)});

        //关闭数据库

        sql.close();

        Log.e("TAG","删除数据成功");

    }

    //改

    public void update(BlackNumber blackNumber)

    {

        //获取数据库连接

        SQLiteDatabase sql = dbHelper.getWritableDatabase();

        //要添加数据的键值对集合

        ContentValues contentValues =new ContentValues();

        contentValues.put("phone_number", blackNumber.getPhonenumber());

        //数据修改

        sql.update("black_number",contentValues,"_id=?",new String[]{String.valueOf(blackNumber.getId())});

        //关闭数据库

        sql.close();

        Log.e("TAG","修改数据成功");

    }

    //查

    //用list<实体类的实例>返回数据

    public List<BlackNumber> getAll()

    {

        List<BlackNumber> rtn = new ArrayList<BlackNumber>();

        //查询数据

        //获取数据库连接

        SQLiteDatabase sql = dbHelper.getWritableDatabase();

        //返回游标

        Cursor cursor = sql.query("black_number", null, null, null, null, null, "_id desc");

        //移动游标，获取数据

        while (cursor.moveToNext())

        {

            //构造实体类的实例，放入List

            rtn.add(new BlackNumber(cursor.getLong(0),cursor.getString(1)));

        }

        Log.e("TAg","记录条数 = "+cursor.getCount());

        sql.close();

        return rtn;

    }

}

MianActivity.java

package com.hanqi.blacklist;

import android.app.AlertDialog;

import android.app.ListActivity;

import android.content.DialogInterface;

import android.os.Bundle;

import android.text.InputType;

import android.view.ContextMenu;

import android.view.MenuItem;

import android.view.View;

import android.view.ViewGroup;

import android.widget.AdapterView;

import android.widget.BaseAdapter;

import android.widget.EditText;

import android.widget.ListView;

import android.widget.TextView;

import android.widget.Toast;

import java.util.List;

public class MianActivity extends ListActivity {

    private ListView lv1;

    private List<BlackNumber> data;

    private BlackListAdapter dla;

    private int position;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_mian);

        //lv1 = (ListView)findViewById(R.id.lv_1);

        lv1 = getListView();

        //获取数据集合

        BlackNumberDAO bd = new BlackNumberDAO(this);

        data = bd.getAll();

        dla = new BlackListAdapter();

        //设置适配器

        lv1.setAdapter(dla);

        //设置上下文菜单的监听

        lv1.setOnCreateContextMenuListener(this);

    }

    //上下文菜单被点击

    @Override

    public boolean onContextItemSelected(MenuItem item) {

        final BlackNumber bn =data.get(position);

        switch (item.getItemId())

        {

            case 0://修改

                final EditText et = new EditText(this);

                et.setInputType(InputType.TYPE_CLASS_PHONE);

                et.setText(bn.getPhonenumber());

                //弹出对话框

                new AlertDialog.Builder(this)

                        .setTitle("修改黑名单")

                        .setView(et)

                        .setNeutralButton("取消",null)

                        .setPositiveButton("保存", new DialogInterface.OnClickListener() {

                            @Override

                            public void onClick(DialogInterface dialog, int which) {

                                //获取修改后的值

                                bn.setPhonenumber(et.getText().toString());

                                //执行数据库修改操作

                                BlackNumberDAO  bnd = new BlackNumberDAO(MianActivity.this);

                                bnd.update(bn);

                                //更新集合

                                //bn和data里面的对象，指向同一个内存地址

                                //如果bn 被修改了， data里面的对象也同时

                                //这就是引用类型的特点

                                //通知刷新列表

                                dla.notifyDataSetChanged();

                                Toast.makeText(MianActivity.this, "修改成功", Toast.LENGTH_SHORT).show();

                            }

                        })

                        .show();

                break;

            case 1://删除

                BlackNumberDAO bd = new BlackNumberDAO(this);

                //需要id 数据库删除了

                bd.delete(bn.getId());

                //刷新界面

                data.remove(position);

                //通知刷新

                dla.notifyDataSetChanged();

                break;

        }

        return super.onContextItemSelected(item);

    }

    //创建上下文菜单

    public void onCreateContextMenu(ContextMenu menu,View v,ContextMenu.ContextMenuInfo menuInfo)

    {

        super.onCreateContextMenu(menu, v, menuInfo);

        menu.add(0, 0, 0, "修改");

        menu.add(0,1,1,"修改");

        //获取长按的适配器信息

        AdapterView.AdapterContextMenuInfo acm = (AdapterView.AdapterContextMenuInfo)menuInfo;

        position=acm.position;

    }

    //列表的适配器

    class BlackListAdapter extends BaseAdapter

    {

        @Override

        public int getCount() {

            return data.size();

        }

        @Override

        public Object getItem(int position) {

            return data.get(position);

        }

        @Override

        public long getItemId(int position) {

            return data.get(position).getId();

        }

        @Override

        public View getView(int position, View convertView, ViewGroup parent) {

            //判断可复用的视图是否为空

            if(convertView == null)

            {

                //获取视图

                convertView = View.inflate(MianActivity.this,android.R.layout.simple_list_item_1,null);

            }

            //给视图绑定视图

            TextView tv = (TextView)convertView.findViewById(android.R.id.text1);

            tv.setText(data.get(position).getPhonenumber());

            return convertView;

        }

    }

    public void bt1_onclick(View v)

    {

        final EditText editText =  new EditText(this);

        editText.setHint("输入电话号码");

        //editText.setLayoutParams(new ActionBar.LayoutParams());

        editText.setInputType(InputType.TYPE_CLASS_PHONE);

        //构造在定义对话框

        new AlertDialog.Builder(this)

                .setTitle("添加黑名单")

                .setView(editText)

                .setNeutralButton("取消",null)

                .setPositiveButton("保存", new DialogInterface.OnClickListener() {

                    @Override

                    public void onClick(DialogInterface dialog, int which) {

                        //构造实体类

                        BlackNumber blackNumber = new BlackNumber(editText.getText().toString());

                        //调用DAO类，保存数据

                        BlackNumberDAO blackNumberDAO = new BlackNumberDAO(MianActivity.this);

                        blackNumberDAO.insert(blackNumber);

                        //添加数据到集合数据集合的顶部

                        data.add(0,blackNumber);

                        //通知适配器刷新ListView

                        dla.notifyDataSetChanged();

                        Toast.makeText(MianActivity.this, "数据保存成功", Toast.LENGTH_SHORT).show();

                    }

                })

                .show();

    }

}

相关文章