Android 数据库编程SQLite

一、实验内容

1. 构建应用界面布局

（1）新建一个安卓工程，在默认的layout主界面中添加一个列表(ListView)，列表绑定一个SimpleAdapter关联学生信息（学号、姓名）。
（2）为ListView添加上下文菜单，菜单中包含两个选项（修改学生，删除学生），分别对应学生信息的修改和删除操作。为每个选项添加点击事件完成相应的操作，其中点击修改学生时启动“updateStu”Activity组件。
（3）在ListView下方添加一个按钮(Button)，内容为“添加学生”，为按钮添加点击事件，单击按钮是启动“addStu”Activity组件。
（4）为“updateStu”和“addStu”Activity组件构建对应的layout界面stuinfo.xml，添加对应的文本框和输出框显示某一个学生的信息（学号、姓名、性别、电话），添加确认按钮(Button)。注意：当由“addStu”Activity启动此界面时，相关输入内容为空白，当由“updateStu”Activity启动此界面时，相关输入内容为该学生的原始信息。

2. 利用SQLite构建数据库交互组件

（1）新建一个DpHelper类继承SQLiteOpenHelper，通过构建方法启动数据库连接。构建createtable()方法完成建表操作，在数据库中建立一个学生信息表：

（2）构建insert(String id, String name, String sex, String phone)方法实现插入记录操作，构建 delete(String id)方法实现删除记录操作，构建update(String id, String name, String sex, String phone)方法实现更新记录操作，构建select(String id)方法实现查询某一记录操作，构建selectAll()方法实现查询所有记录操作。

3. 实现学生信息管理应用

（1）完善相关代码，实现学生信息管理应用的基本功能。包括：

1. 学生信息列表：进入应用程序后，在ListView中自动加载所有已有学生的信息（学号，姓名）。
2. 添加学生：单击“添加学生”按钮，打开相应的界面stuinfo.xml填写新学生信息，单击“确认”按钮后完成
3. 添加学生操作。要求程序能够识别用户输入完整性（学号、姓名为必填项），如果新学生学号与现有学生相同，应提示更换学号。添加完成后返回主界面，同时更新ListView的内容。
4. 删除学生：根据ListView长按位置得到要删除的学生的学号信息，完成删除操作，删除后更新ListView的内容。
5. 修改学生：根据ListView长按位置得到要修改的学生的相关信息，打开相应的界面stuinfo.xml，将学生原始信息自动填入对应的输入框中，点击确认按钮后完成更新学生信息操作。要求程序能够识别用户输入完整性（学号、姓名为必填项），如果新学生学号与现有学生相同，应提示更换学号。修改完成后返回主界面，同时更新ListView的内容。

（2）测试相关功能，添加若干条学生信息（3条以上），再进行信息修改、删除操作的测试。

二：演示截图

数据库：

没有填入数据时，显示学生，姓名，性别，手机：

插入学生数据：

插入数据后：

单击某行进行学生信息修改：

长按提示是否删除，确认后删除：

如果添加的学号重复：提示学号重复

实现代码

<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:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin" android:paddingBottom="@dimen/activity_vertical_margin"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">
        <TextView
            android:layout_width="@dimen/item_no_width"
            android:layout_height="wrap_content"
            android:gravity="left"
            android:textSize="@dimen/item_font_size"
            android:text="@string/no"/>
        <TextView
            android:layout_width="@dimen/item_name_width"
            android:layout_height="wrap_content"
            android:gravity="left"
            android:textSize="@dimen/item_font_size"
            android:text="@string/name"/>
        <TextView
            android:layout_width="@dimen/item_name_width"
            android:layout_height="wrap_content"
            android:gravity="left"
            android:textSize="@dimen/item_font_size"
            android:text="性别:"/>
        <TextView
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:gravity="left"
            android:textSize="@dimen/item_font_size"
            android:text="@string/phone"/>

    </LinearLayout>

    <ListView
        android:id="@+id/lv_contact"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content">

    </ListView>

    <Button
        android:id="@+id/btn_add"
        android:layout_width="411dp"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom"
        android:layout_marginTop="@dimen/margin_fix"
        android:background="@color/btn_blue"
        android:text="@string/add"
        android:textSize="@dimen/btn_add_size" />

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent" android:layout_height="match_parent"
    android:orientation="horizontal">
    <TextView
        android:layout_width="@dimen/item_no_width"
        android:layout_height="wrap_content"
        android:gravity="left"
        android:id="@+id/contact_no"
        android:textSize="@dimen/item_font_size"/>
    <TextView
        android:layout_width="@dimen/item_name_width"
        android:layout_height="wrap_content"
        android:gravity="left"
        android:id="@+id/contact_name"
        android:textSize="@dimen/item_font_size"/>

    <TextView
        android:id="@+id/contact_sex"
        android:layout_width="90dp"
        android:layout_height="wrap_content"
        android:gravity="left"
        android:textSize="@dimen/item_font_size" />

    <TextView
        android:id="@+id/contact_phonenumber"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:gravity="left"
        android:textSize="@dimen/item_font_size" />
</LinearLayout>

<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:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin" android:paddingBottom="@dimen/activity_vertical_margin"
    android:orientation="vertical"
    tools:context="com.wsine.west.exp7.DetailActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:id="@+id/detail_title"
        android:textSize="@dimen/title_size"/>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:text="@string/no"
            android:textSize="@dimen/label_size"
            android:gravity="center_vertical"/>
        <EditText
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:id="@+id/Et_no"
            android:textSize="@dimen/label_size"/>
    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:text="@string/name"
            android:textSize="@dimen/label_size"
            android:gravity="center_vertical"/>
        <EditText
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:id="@+id/Et_name"
            android:textSize="@dimen/label_size"/>
    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:text="性别:"
            android:textSize="@dimen/label_size"
            android:gravity="center_vertical"/>
        <EditText
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:id="@+id/Et_sex"
            android:textSize="@dimen/label_size"/>
    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:text="@string/phone"
            android:textSize="@dimen/label_size"
            android:gravity="center_vertical"/>
        <EditText
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:id="@+id/Et_phone"
            android:textSize="@dimen/label_size"/>
    </LinearLayout>

    <Button
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="@dimen/margin_fix"
        android:layout_gravity="center"
        android:id="@+id/btn_confirm"
        android:textSize="@dimen/btn_add_size"
        android:text="@string/confirm"
        android:background="@color/btn_blue"/>

</LinearLayout>

package com.wsine.west.exp7;

/**
 * Created by West on 2015/11/25.
 */
public class Contact {
    private  int id;
    private String no;
    private String sex;
    private String name;
    private String phoneNumber;

    public Contact(String no, String name, String sex, String phoneNumber) {
        this.no = no;
        this.sex = sex;
        this.name = name;
        this.phoneNumber = phoneNumber;
    }

    public Contact(int id, String no, String name, String sex, String phoneNumber) {
        this.id = id;
        this.no = no;
        this.sex = sex;
        this.name = name;
        this.phoneNumber = phoneNumber;
    }

    public Contact() {}
    public Contact(String _name, String _phoneNumber) {
        this.name = _name;
        this.phoneNumber = _phoneNumber;
    }
    public Contact(String _no, String _name, String _phoneNumber) {
        this.no = _no;
        this.name = _name;
        this.phoneNumber = _phoneNumber;
    }

    public String getNo() { return no; }
    public void setNo(String _no) { this.no = _no; }

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }

    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 void setId(int id) {
        this.id = id;
    }

    public int getId() {
        return id;
    }
}

package com.wsine.west.exp7;

import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.widget.SimpleAdapter;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

/**
 * Created by West on 2015/11/25.
 */
public class MySimpleAdapter extends SimpleAdapter {
    private ArrayList<Map<String, String>> mData;

    public ArrayList<Map<String, String>> getmData() {
        return mData;
    }

    public MySimpleAdapter(Context context, List<? extends Map<String, ?>> data,
                           int resource, String[] from, int[] to) {
        super(context, data, resource, from, to);
        this.mData = (ArrayList<Map<String, String>>)data;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        final int mPosition = position;
        return super.getView(position, convertView, parent);
    }
}

package com.wsine.west.exp7;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.widget.Toast;

import static android.widget.Toast.LENGTH_SHORT;

/**
 * Created by West on 2015/11/25.
 */
public class MyDatabaseHelper extends SQLiteOpenHelper {
    private static final String DB_NAME = "Contacts.db";
    private static final String TABLE_NAME = "Contacts";
    private static final int DB_VERSION = 1;

    public MyDatabaseHelper(Context context) {
        super(context, DB_NAME, null, DB_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        String CREATE_TABLE = "create table " + TABLE_NAME
                + " (_id integer primary key autoincrement, "
                + "_no text not null, "
                + "_name text not null, "
                + "_sex text,"
                + "_pnumber text);";
        db.execSQL(CREATE_TABLE);
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        String DROP_TABLE = "DROP TABLE IF exists " + TABLE_NAME;
        db.execSQL(DROP_TABLE);
        onCreate(db);
    }

    public long insert(Contact entity) {
        SQLiteDatabase db = getWritableDatabase();
        ContentValues values = new ContentValues();
        values.put("_no", entity.getNo());
        values.put("_name", entity.getName());
        values.put("_sex", entity.getSex());
        values.put("_pnumber", entity.getPhoneNumber());
        long id = db.insert(TABLE_NAME, null, values);
        db.close();
        return id;
    }

    public int update(Contact entity,String oldNo) {
        SQLiteDatabase db = getWritableDatabase();
        String whereClause = "_no = ?";
        String[] whereArgs = { oldNo};

        ContentValues values = new ContentValues();
        values.put("_no", entity.getNo());
        values.put("_name", entity.getName());
        values.put("_sex", entity.getSex());
        values.put("_pnumber", entity.getPhoneNumber());
        int rows = db.update(TABLE_NAME, values, whereClause, whereArgs);
        db.close();
        return rows;
    }

    public int delete(Contact entity) {
        SQLiteDatabase db = getWritableDatabase();
        String whereClause = "_no = ?";
        String[] whereArgs = { entity.getNo() };

        int rows = db.delete(TABLE_NAME, whereClause, whereArgs);
        db.close();
        return rows;
    }

    public Cursor query() {
        SQLiteDatabase db = getReadableDatabase();
        return db.query(TABLE_NAME, null, null, null, null, null, null);
    }

}

package com.wsine.west.exp7;

import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.database.Cursor;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.Button;
import android.widget.ListView;
import android.widget.Toast;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class MainActivity extends AppCompatActivity {

    private MyDatabaseHelper myDatabaseHelper = new MyDatabaseHelper(MainActivity.this);
    private List<Map<String, String>> dataList = new ArrayList<Map<String, String>>();

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

        MySimpleAdapter mySimpleAdapter=updateListView();
        final ArrayList<Map<String, String>> mData=mySimpleAdapter.getmData();

        Button btnAdd = (Button)this.findViewById(R.id.btn_add);
        btnAdd.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent intent = new Intent(MainActivity.this, DetailActivity.class);
                Bundle bundle = new Bundle();
                int i=-1;
                for (Map<String, String> m : mData){
                    i++;
                    Collection<String> valueCollection = m.values();
                    final  int  size = valueCollection.size();

                    List<String> valueList =  new  ArrayList<String>(valueCollection);

                    String[] valueArray =  new  String[size];
                    m.values().toArray(valueArray);
                    bundle.putString("No"+i, valueArray[3]);
                }
                bundle.putBoolean("AddorNot", true);
                intent.putExtras(bundle);
                int requestCode = 1;
                startActivityForResult(intent, requestCode);
            }
        });

        ListView lv = (ListView)this.findViewById(R.id.lv_contact);
        lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                ListView listView = (ListView) parent;
                HashMap<String, String> map = (HashMap<String, String>)listView.getItemAtPosition(position);

                Intent intent = new Intent(MainActivity.this, DetailActivity.class);
                Bundle bundle = new Bundle();
                bundle.putBoolean("AddorNot", false);
                int i=-1;
                for (Map<String, String> m : mData){
                    i++;
                    Collection<String> valueCollection = m.values();
                    final  int  size = valueCollection.size();

                    List<String> valueList =  new  ArrayList<String>(valueCollection);

                    String[] valueArray =  new  String[size];
                    m.values().toArray(valueArray);
                    bundle.putString("No"+i, valueArray[3]);
                    }
                bundle.putString("oldNo", map.get("no"));
                bundle.putString("oldName", map.get("name"));
                bundle.putString("oldSex", map.get("sex"));
                bundle.putString("oldPNumber", map.get("pnumber"));
                intent.putExtras(bundle);
                int requestCode = 2;
                startActivityForResult(intent, requestCode);
            }
        });
        lv.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
            @Override
            public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
                ListView listView = (ListView) parent;
                final HashMap<String, String> map = (HashMap<String, String>)listView.getItemAtPosition(position);
                AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
                builder.setMessage("确认删除吗？");
                builder.setTitle("提示");
                builder.setPositiveButton("确认", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialogInterface, int i) {
                        try {
                            myDatabaseHelper.delete(new Contact(map.get("no"), map.get("name"), map.get("sex"),map.get("pnumber")));
                            updateListView();
                        } catch (Exception e) {
                            Log.d("Hint", "Remove failed!");
                        }
                    }
                });
                builder.setNegativeButton("取消", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialogInterface, int i) {
                        // nothing to do
                    }
                });
                builder.show();
                return true;
            }
        });
    }

    private void setData(List<Map<String, String>> mDataList) {
        Map<String, String> mData;
        Cursor c = myDatabaseHelper.query();
        while (c.moveToNext()) {
            mData = new HashMap<String, String>();
            mData.put("no", c.getString(c.getColumnIndex("_no")));
            mData.put("name", c.getString(c.getColumnIndex("_name")));
            mData.put("sex", c.getString(c.getColumnIndex("_sex")));
            mData.put("pnumber", c.getString(c.getColumnIndex("_pnumber")));
            mDataList.add(mData);

        }
    }

    private MySimpleAdapter updateListView() {
        dataList.clear();
        setData(dataList);
        MySimpleAdapter mySimpleAdapter = new MySimpleAdapter(this, dataList, R.layout.contact_item,
                new String[] { "no", "name","sex", "pnumber" },
                new int[] { R.id.contact_no, R.id.contact_name,R.id.contact_sex, R.id.contact_phonenumber });
        ListView lv = (ListView)this.findViewById(R.id.lv_contact);
        lv.setAdapter(mySimpleAdapter);
        return  mySimpleAdapter;
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        Log.d("Hint", "requestCode = " + requestCode);
        Log.d("Hint", "resultCode = " + resultCode);
        if (resultCode == 0)
            return;
        String oldNo= data.getStringExtra("_oldNo");
        String newNo = data.getStringExtra("_newNo");
        String newName = data.getStringExtra("_newName");
        String newSex = data.getStringExtra("_newSex");
        String newPNumber = data.getStringExtra("_newPNumber");
        switch (requestCode) {
            case 1:
                myDatabaseHelper.insert(new Contact(newNo, newName,newSex, newPNumber));
                break;
            case 2:
                int i=myDatabaseHelper.update(new Contact(newNo, newName,newSex, newPNumber),oldNo);
                Toast.makeText(this,""+i+"个修改成功", Toast.LENGTH_SHORT).show();
                break;
            default:
                break;
        }
        updateListView();
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }
}

package com.wsine.west.exp7;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

public class DetailActivity extends AppCompatActivity {

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

        TextView tvTitle = (TextView)this.findViewById(R.id.detail_title);
        final EditText edtNo = (EditText)this.findViewById(R.id.Et_no);
        final EditText edtName = (EditText)this.findViewById(R.id.Et_name);
        final EditText edtSex = (EditText)this.findViewById(R.id.Et_sex);
        final EditText edtPNumber = (EditText)this.findViewById(R.id.Et_phone);

        final Bundle bundle = getIntent().getExtras();
        final boolean addOrNot = bundle.getBoolean("AddorNot");
        final int[] data=bundle.getIntArray("data");
        if (addOrNot) {
            tvTitle.setText(getResources().getString(R.string.titleAdd));
            edtNo.setText("");
            edtName.setText("");
            edtSex.setText("");
            edtPNumber.setText("");
        } else {
            tvTitle.setText(getResources().getString(R.string.titleModify));
            edtNo.setText(bundle.getString("oldNo"));
            edtName.setText(bundle.getString("oldName"));
            edtSex.setText(bundle.getString("oldSex"));
            edtPNumber.setText(bundle.getString("oldPNumber"));
        }

        Button btnConfirm = (Button)this.findViewById(R.id.btn_confirm);
        btnConfirm.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String newNo = edtNo.getText().toString();
                String newName = edtName.getText().toString();
                String newSex = edtSex.getText().toString();
                String newPNumber = edtPNumber.getText().toString();
                Intent intent = new Intent();
                intent.putExtra("_oldNo",bundle.getString("oldNo"));
                intent.putExtra("_newNo", newNo);
                intent.putExtra("_newName", newName);
                intent.putExtra("_newSex", newSex);
                intent.putExtra("_newPNumber", newPNumber);

                for(int i=0;bundle.getString("No"+i)!=null;i++)
                {   System.out.println("第"+i+"行");
                    System.out.println(bundle.getString("No"+i));
                    System.out.println(newNo);
                    if (newNo.isEmpty()
                            || newPNumber.isEmpty()
                            || newName.isEmpty()) {
                        Toast.makeText(getApplicationContext(), getResources().getString(R.string.msgWarning),Toast.LENGTH_SHORT).show();
                        return;
                    }
                    else if(newNo.equals(bundle.getString("No"+i))&&!newNo.equals(bundle.getString("oldNo")))
                    {
                        Toast.makeText(getApplicationContext(), getResources().getString(R.string.msgWarning2),Toast.LENGTH_SHORT).show();
                        return;
                    }
                }
                int resultCode = 0;
                if (addOrNot)   resultCode = 1;
                else            resultCode = 2;

                DetailActivity.this.setResult(resultCode, intent);
                DetailActivity.this.finish();
            }
        });
    }

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        if(keyCode == KeyEvent.KEYCODE_BACK) {
            int resultCode = 0;
            DetailActivity.this.setResult(resultCode);
            DetailActivity.this.finish();
        }
        return true;
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_detail, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }
}

<resources>
    <string name="app_name">Exp7</string>

    <string name="hello_world">Hello world!</string>
    <string name="action_settings">Settings</string>
    <string name="title_activity_detail">DetailActivity</string>

    <string name="add">Add</string>

    <string name="no">学号:</string>
    <string name="name">姓名:</string>
    <string name="phone">手机:</string>
    <string name="confirm">确定</string>
    
    <string name="titleAdd">添加联系人</string>
    <string name="titleModify">修改联系人</string>

    <string name="msgWarning">您输入的内容为空</string>
    <string name="msgWarning2">你输入的学号重复</string>
</resources>

源码下载：https://download.csdn.net/download/qq_45808700/19525532