Android——通讯录

 <?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.contacts.MainActivity"
     android:orientation="vertical">

     <ListView
         android:layout_width="match_parent"
         android:layout_height="0dp"
         android:layout_weight="1"
         android:id="@+id/lv_1">
     </ListView>
     <Button
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:text="添加通讯录名单"
         android:onClick="add_onClick"/>
 </LinearLayout>

activity_main

 <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:orientation="horizontal"
     android:layout_width="match_parent"
     android:layout_height="match_parent">

     <TextView
         android:layout_width="0dp"
         android:layout_height="wrap_content"
         android:layout_weight="1"
         android:id="@+id/tv_1"
         android:textSize="30dp"
         android:height="40dp"/>
     <TextView
         android:layout_width="0dp"
         android:layout_height="wrap_content"
         android:layout_weight="1"
         android:id="@+id/tv_2"
         android:textSize="30dp"
         android:height="40dp"/>
 </LinearLayout>

contact1_layout

 <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:orientation="vertical"
     android:layout_width="match_parent"
     android:layout_height="match_parent">

     <EditText
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:hint="请输入姓名"
         android:id="@+id/et_1"/>
     <EditText
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:hint="请输入电话号码"
         android:inputType="number"
         android:id="@+id/et_2"/>
 </LinearLayout>

contact_layout

 package com.hanqi.contacts.com.hanqi.contacts.orm;

 /**
  * Created by lenovo on 2016/6/8.
  */
 public class Contacts {

     private long id;
     private String name;
     private String phoneNumber;

     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 String getPhoneNumber() {
         return phoneNumber;
     }

     public void setPhoneNumber(String phoneNumber) {
         this.phoneNumber = phoneNumber;
     }

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

     public Contacts(String name,String phoneNumber) {
         this.name = name;
         this.phoneNumber = phoneNumber;
     }
 }

Contacts

 package com.hanqi.contacts.com.hanqi.contacts.orm;

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

 /**
  * Created by lenovo on 2016/6/8.
  */
 public class CTHelper extends SQLiteOpenHelper {
     public CTHelper(Context context) {
         super(context, "contacts.db", null, 1);
     }

     @Override
     public void onCreate(SQLiteDatabase db) {
         //1.执行创建数据库的语句
         String sql = "CREATE TABLE t_contacts " +
                 "(_id  INTEGER NOT NULL," +
                 "name  VARCHAR(20) NOT NULL,"
                 +"phone_number  VARCHAR(20) NOT NULL,"
                 +"PRIMARY KEY (\"_id\"))";
         db.execSQL(sql);
         Log.e("TAG", "表创建成功");
     }

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

     }
 }

CTHelper

 package com.hanqi.contacts.com.hanqi.contacts.orm;

 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 2016/6/8.
  */
 public class ContactsDAO {
     private final String TABLE_NAME = "t_contacts";
     private CTHelper ch;

     public ContactsDAO(Context context)
     {
         ch = new CTHelper(context);
     }
     //增
     public long insert(Contacts contacts)
     {
         long rtn = 0;
         SQLiteDatabase sd = ch.getWritableDatabase();
         //insert into t_contacts (phoneNumber) values()
         ContentValues cv = new ContentValues();
         cv.put("name",contacts.getName());
         cv.put("phone_number",contacts.getPhoneNumber());
         rtn = sd.insert("t_contacts",null,cv);
         sd.close();
         return rtn;
     }
     //删
     public int delete(long id)
     {
         int rtn = 0;
         //delete from t_contacts where = ?
         SQLiteDatabase sd = ch.getWritableDatabase();
         rtn = sd.delete(TABLE_NAME,"_id = ?",new String[]{id+""});
         sd.close();
         return rtn;
     }
     //改
     public int update(Contacts contacts)
     {
         int rtn = 0;
         //update t_contacts set phone_number = ? and name = ? where id = ?
         SQLiteDatabase sd = ch.getWritableDatabase();
         ContentValues cv = new ContentValues();
         cv.put("name",contacts.getName());
         cv.put("phone_number",contacts.getPhoneNumber());
         rtn = sd.update(TABLE_NAME,cv,"_id = ?",new String[]{contacts.getId()+""});
         sd.close();
         return rtn;
     }
     //查
     public ArrayList<Contacts> getAll()
     {
         //select * from t_contacts
         //查询之后得到游标结果集
         ArrayList<Contacts> contacts = new ArrayList<>();
         SQLiteDatabase sd = ch.getWritableDatabase();
         Cursor cursor = sd.query(TABLE_NAME, null, null, null, null, null, "_id desc");
         while (cursor.moveToNext())
         {
             Contacts contacts1 = new Contacts(cursor.getLong(0),cursor.getString(1),cursor.getString(2));
             contacts.add(contacts1);
         }
         cursor.close();
         sd.close();
         return contacts;
     }
 }

ContactsDAO

 package com.hanqi.contacts;

 import android.app.AlertDialog;
 import android.content.DialogInterface;
 import android.os.Bundle;
 import android.support.v7.app.AppCompatActivity;
 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 com.hanqi.contacts.com.hanqi.contacts.orm.Contacts;
 import com.hanqi.contacts.com.hanqi.contacts.orm.ContactsDAO;

 import java.util.ArrayList;

 public class MainActivity extends AppCompatActivity {
     ListView lv_1;
     ContactsDAO ctd = new ContactsDAO(this);
     ArrayList<Contacts> act;
     CTAdapter cta;
     //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);

         lv_1.setOnCreateContextMenuListener(this);
         //获取数据集合
         act = ctd.getAll();
         //显示数据
         cta = new CTAdapter();
         lv_1.setAdapter(cta);

     }
     //重写创建上下文菜单的方法
     @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");
         //获取长按的数据信息
         //1.得到菜单信息
         AdapterView.AdapterContextMenuInfo acmi =
                 (AdapterView.AdapterContextMenuInfo)menuInfo;
         //2.得到数据在集合中的索引
         index = acmi.position;
     }
     //响应菜单点击的回调方法
     @Override
     public boolean onContextItemSelected(MenuItem item) {
         switch (item.getItemId())
         {
             case 1:
                 final View view = View.inflate(this,R.layout.contact_layout,null);
                 new AlertDialog.Builder(this)
                         .setTitle("添加通讯录")
                         .setView(view)
                         .setCancelable(false)
                         .setNegativeButton("取消", null)
                         .setPositiveButton("确定", new DialogInterface.OnClickListener() {
                             @Override
                             public void onClick(DialogInterface dialog, int which) {
                                 EditText et_1 = (EditText)view.findViewById(R.id.et_1);
                                 EditText et_2 = (EditText)view.findViewById(R.id.et_2);
                                 Contacts contacts = act.get(index);
                                 contacts.setName(et_1.getText().toString());
                                 contacts.setPhoneNumber(et_2.getText().toString());
                                 if(ctd.update(contacts)>0)
                                 {
                                     Toast.makeText(MainActivity.this, "修改成功", Toast.LENGTH_SHORT).show();
                                     cta.notifyDataSetChanged();
                                 }
                                 else
                                 {
                                     Toast.makeText(MainActivity.this, "修改失败", Toast.LENGTH_SHORT).show();
                                 }
                             }
                         })
                         .show();
                 break;
             case 2:
                 new AlertDialog.Builder(this)
                         .setTitle("确认对话框")
                         .setCancelable(false)
                         .setNegativeButton("取消",null)
                         .setPositiveButton("确认", new DialogInterface.OnClickListener() {
                             @Override
                             public void onClick(DialogInterface dialog, int which) {
                                 ctd.delete(act.get(index).getId());
                                 Toast.makeText(MainActivity.this, "删除成功", Toast.LENGTH_SHORT).show();
                                 act = ctd.getAll();
                                 cta.notifyDataSetChanged();
                             }
                         })
                         .show();
                 break;
         }
         return super.onContextItemSelected(item);
     }

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

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

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

         @Override
         public View getView(int position, View convertView, ViewGroup parent) {
             //得到数据
             Contacts contacts = act.get(position);
             //得到视图
             if (convertView == null)
             {
                 convertView = View.inflate(MainActivity.this,R.layout.contact1_layout,null);
             }
             //视图和数据做显式匹配
             TextView textView = (TextView)convertView.findViewById(R.id.tv_1);
             textView.setText(contacts.getName());
             TextView textView1 = (TextView)convertView.findViewById(R.id.tv_2);
             textView1.setText(contacts.getPhoneNumber());
             return convertView;
         }
     }
     public void add_onClick(View v)
     {
         final View view = View.inflate(this,R.layout.contact_layout,null);
         new AlertDialog.Builder(this)
                 .setTitle("添加通讯录")
                 .setView(view)
                 .setCancelable(false)
                 .setNegativeButton("取消", null)
                 .setPositiveButton("保存", new DialogInterface.OnClickListener() {
                     @Override
                     public void onClick(DialogInterface dialog, int which) {
                         EditText et_1 = (EditText)view.findViewById(R.id.et_1);
                         EditText et_2 = (EditText)view.findViewById(R.id.et_2);
                         Contacts contacts = new Contacts(et_1.getText().toString(), et_2.getText().toString());
                         long l = ctd.insert(contacts);
                         if (l > 0) {
                             Toast.makeText(MainActivity.this, "保存成功", Toast.LENGTH_SHORT).show();
                             act = ctd.getAll();
                             cta.notifyDataSetChanged();
                         } else {
                             Toast.makeText(MainActivity.this, "保存失败", Toast.LENGTH_SHORT).show();
                         }
                     }
                 })
                 .show();
     }
 }

MainActivity