Android中结合OrmLite for android组件对SQLite的CRUD(增删改查)操作实例

         本博客文章中曾经提到过Ormlite的第三方组件包，Ormlite 是一种ORM工具，并且是一种轻量级别的工具。我们可以使用它来对Android中内嵌的sqlite数据库进行相关的操作。Android 的应用程序应使用 Ormlite for android 版本来进行相关的开发。Ormlite是对android提供的sqlite部分的API进行了封装。提供了更加方便的接口来供使用。

      本文以一个学生的信息实例程序来展示如何使用ormlite for android的第三方组件来开发Sqlite的C[增加]，R[查询]，U[更新]，D[查询]应用程序，以便更方便的对sqlite数据库的操作。我们先看下程序的结构图：

【1】.程序结构图如下：

其中包com.andyidea.bean下Student.java为实体类，包com.andyidea.db下DatabaseHelper.java为数据库辅助类，包com.andyidea.ormsqlite下的MainActivity.java和StudentListActivity.java是界面信息类。同时我们别忘了在根目录下创建一个lib的文件夹，把第三方组件包ormlite-android-4.31.jar ，ormlite-core-4.31.jar，ormlite-jdbc-4.31.jar放到lib文件夹下，然后在项目中引用这三个包就OK了。

【2】布局文件源码如下：

main.xml源码：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:padding="5dip">
    <TextView  
    android:layout_width="fill_parent"  android:layout_height="wrap_content"
    android:gravity="center" android:text="ORMLite-AddPage"/>
    <LinearLayout
       android:layout_width="fill_parent" android:layout_height="wrap_content"
       android:orientation="horizontal" android:padding="1dip" android:gravity="center_vertical">
       <TextView 
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:text="学号: "/>
       <EditText
          android:id="@+id/stuno"
          android:layout_width="fill_parent"
          android:layout_height="wrap_content"/>
    </LinearLayout>
    <LinearLayout
       android:layout_width="fill_parent" android:layout_height="wrap_content"
       android:orientation="horizontal" android:padding="1dip" android:gravity="center_vertical">
       <TextView 
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:text="姓名: "/>
       <EditText
          android:id="@+id/name"
          android:layout_width="fill_parent"
          android:layout_height="wrap_content"/>
    </LinearLayout>
    <LinearLayout
       android:layout_width="fill_parent" android:layout_height="wrap_content"
       android:orientation="horizontal" android:padding="1dip" android:gravity="center_vertical">
       <TextView 
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:text="年龄: "/>
       <EditText
          android:id="@+id/age"
          android:layout_width="fill_parent"
          android:layout_height="wrap_content"/>
    </LinearLayout>
    <LinearLayout
       android:layout_width="fill_parent" android:layout_height="wrap_content"
       android:orientation="horizontal" android:padding="1dip" android:gravity="center_vertical">
       <TextView 
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:text="性别: "/>
       <EditText
          android:id="@+id/sex"
          android:layout_width="fill_parent"
          android:layout_height="wrap_content"/>
    </LinearLayout>
    <LinearLayout
       android:layout_width="fill_parent" android:layout_height="wrap_content"
       android:orientation="horizontal" android:padding="1dip" android:gravity="center_vertical">
       <TextView 
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:text="分数: "/>
       <EditText
          android:id="@+id/score"
          android:layout_width="fill_parent"
          android:layout_height="wrap_content"/>
    </LinearLayout>
    <LinearLayout
       android:layout_width="fill_parent" android:layout_height="wrap_content"
       android:orientation="horizontal" android:padding="1dip" android:gravity="center_vertical">
       <TextView 
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:text="地址: "/>
       <EditText
          android:id="@+id/address"
          android:layout_width="fill_parent"
          android:layout_height="wrap_content"/>
    </LinearLayout>
    
</LinearLayout>

students.xml源码：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:orientation="vertical"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent">
  <TextView  
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content"
    android:gravity="center"
    android:text="ORMLite-Students"/>
  <ListView
    android:id="@+id/stulist"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"/>
</LinearLayout>

studentitem.xml源码：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:orientation="horizontal"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent">
  <TextView
     android:id="@+id/itemno"
     android:layout_width="fill_parent"
     android:layout_height="wrap_content"
     android:layout_weight="1"
     android:text="学号"
     android:gravity="center"/>
  <TextView
     android:id="@+id/itemname"
     android:layout_width="fill_parent"
     android:layout_height="wrap_content"
     android:layout_weight="1"
     android:text="姓名"
     android:gravity="center"/>
  <TextView
     android:id="@+id/itemscore"
     android:layout_width="fill_parent"
     android:layout_height="wrap_content"
     android:layout_weight="1"
     android:text="分数"
     android:gravity="center"/>
</LinearLayout>

【3】包com.andyidea.bean下Student.java源码：

package com.andyidea.bean;

import java.io.Serializable;
import com.j256.ormlite.field.DatabaseField;

public class Student implements Serializable {

	private static final long serialVersionUID = -5683263669918171030L;
	
	@DatabaseField(id=true)
	private String stuNO;
	@DatabaseField
	private String name;
	@DatabaseField
	private int age;
	@DatabaseField
	private String sex;
	@DatabaseField
	private double score;
	@DatabaseField
	private String address;
	
	public String getStuNO() {
		return stuNO;
	}
	public void setStuNO(String stuNO) {
		this.stuNO = stuNO;
	}
	
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	
	public int getAge() {
		return age;
	}
	public void setAge(int age) {
		this.age = age;
	}
	
	public String getSex() {
		return sex;
	}
	public void setSex(String sex) {
		this.sex = sex;
	}
	
	public double getScore() {
		return score;
	}
	public void setScore(double score) {
		this.score = score;
	}
	
	public String getAddress() {
		return address;
	}
	public void setAddress(String address) {
		this.address = address;
	}
	
}

【4】包com.andyidea.db下DatabaseHelper.java源码：

package com.andyidea.db;

import java.sql.SQLException;

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

import com.andyidea.bean.Student;
import com.j256.ormlite.android.apptools.OrmLiteSqliteOpenHelper;
import com.j256.ormlite.dao.Dao;
import com.j256.ormlite.support.ConnectionSource;
import com.j256.ormlite.table.TableUtils;

public class DatabaseHelper extends OrmLiteSqliteOpenHelper {
	
	private static final String DATABASE_NAME = "ormlite.db";
	private static final int DATABASE_VERSION = 1;
	
	private Dao<Student,Integer> stuDao = null;
	
	public DatabaseHelper(Context context){
		super(context, DATABASE_NAME, null, DATABASE_VERSION);
	}

	/**
	 * 创建SQLite数据库
	 */
	@Override
	public void onCreate(SQLiteDatabase sqliteDatabase, ConnectionSource connectionSource) {
		try {
			TableUtils.createTable(connectionSource, Student.class);
		} catch (SQLException e) {
			Log.e(DatabaseHelper.class.getName(), "Unable to create datbases", e);
		}
	}

	/**
	 * 更新SQLite数据库
	 */
	@Override
	public void onUpgrade(
			SQLiteDatabase sqliteDatabase, 
			ConnectionSource connectionSource, 
			int oldVer,
			int newVer) {
		try {
			TableUtils.dropTable(connectionSource, Student.class, true);
			onCreate(sqliteDatabase, connectionSource);
		} catch (SQLException e) {
			Log.e(DatabaseHelper.class.getName(), 
					"Unable to upgrade database from version " + oldVer + " to new "
					+ newVer, e);
		}
	}
	
	public Dao<Student,Integer> getStudentDao() throws SQLException{
		if(stuDao == null){
			stuDao = getDao(Student.class);
		}
		return stuDao;
	}

}

【5】包com.andyidea.ormsqlite下源码：

MainActivity.java源码：

package com.andyidea.ormsqlite;

import java.sql.SQLException;

import com.andyidea.bean.Student;
import com.andyidea.db.DatabaseHelper;
import com.j256.ormlite.android.apptools.OrmLiteBaseActivity;
import com.j256.ormlite.dao.Dao;

import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.EditText;

public class MainActivity extends OrmLiteBaseActivity<DatabaseHelper> {
	
	private EditText stuNO;
	private EditText stuName;
	private EditText stuAge;
	private EditText stuSex;
	private EditText stuScore;
	private EditText stuAddress;
	
	private Student mStudent;
	private Dao<Student,Integer> stuDao;
	
	private final int MENU_ADD = Menu.FIRST;
	private final int MENU_VIEWALL = Menu.FIRST+1;
	private final int MENU_EDIT = Menu.FIRST+2;
	
	private Bundle mBundle = new Bundle();
	
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        initializeViews();
    }
    
    /**
     * 初始化UI界面
     */
    private void initializeViews(){
    	stuNO = (EditText)findViewById(R.id.stuno);
    	stuName = (EditText)findViewById(R.id.name);
    	stuAge = (EditText)findViewById(R.id.age);
    	stuSex = (EditText)findViewById(R.id.sex);
    	stuScore = (EditText)findViewById(R.id.score);
    	stuAddress = (EditText)findViewById(R.id.address);
    	
    	mBundle = getIntent().getExtras();
    	if(mBundle!=null && mBundle.getString("action").equals("viewone")){
    		mStudent = (Student)getIntent().getSerializableExtra("entity");
    		setStudentUIData(mStudent);
    	}
    	
    	if(mBundle!=null && mBundle.getString("action").equals("edit")){
    		mStudent = (Student)getIntent().getSerializableExtra("entity");
    		setStudentUIData(mStudent);
    	}
    }
    
    @Override
	public boolean onPrepareOptionsMenu(Menu menu) {
    	if(mBundle!=null && mBundle.getString("action").equals("viewone"))
    		return false;
    	else
    		return super.onPrepareOptionsMenu(menu);
		
	}

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		if(mBundle!=null && mBundle.getString("action").equals("edit")){
			menu.add(1,MENU_EDIT,0,"保存");
		}else{
	    	menu.add(0,MENU_ADD,0,"增加");
	    	menu.add(0,MENU_VIEWALL,0,"查看");
		}
		return super.onCreateOptionsMenu(menu);
	}

	@Override
	public boolean onOptionsItemSelected(MenuItem item) {
		switch (item.getItemId()) {
		case MENU_ADD:
			try {
				stuDao = getHelper().getStudentDao();
				getStudentData();
				if(mStudent != null){
					//创建记录项
					stuDao.create(mStudent);
				}
			} catch (SQLException e) {
				e.printStackTrace();
			}
			break;
		case MENU_VIEWALL:
			Intent intent = new Intent();
			intent.setClass(MainActivity.this, StudentListActivity.class);
			startActivity(intent);
			break;
		case MENU_EDIT:
			try {
				getStudentData();
				stuDao = getHelper().getStudentDao();
				if(mStudent != null){
					//更新某记录项
					stuDao.update(mStudent);
				}
			} catch (SQLException e) {
				e.printStackTrace();
			}
			break;
		default:
			break;
		}
		return super.onOptionsItemSelected(item);
	}

	/**
     * 获取界面值(实体信息)
     */
    private void getStudentData(){
    	mStudent = new Student();
    	mStudent.setStuNO(stuNO.getText().toString());
    	mStudent.setName(stuName.getText().toString());
    	mStudent.setAge(Integer.parseInt(stuAge.getText().toString()));
    	mStudent.setSex(stuSex.getText().toString());
    	mStudent.setScore(Double.parseDouble(stuScore.getText().toString()));
    	mStudent.setAddress(stuAddress.getText().toString());
    }
    
    /**
     * 赋值给UI界面
     * @param student
     */
    private void setStudentUIData(Student student){
    	stuNO.setText(student.getStuNO());
    	stuName.setText(student.getName());
    	stuAge.setText(String.valueOf(student.getAge()));
    	stuSex.setText(student.getSex());
    	stuScore.setText(String.valueOf(student.getScore()));
    	stuAddress.setText(student.getAddress());
    }
}

StudentListActivity.java源码：

package com.andyidea.ormsqlite;

import java.sql.SQLException;
import java.util.List;

import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.os.Bundle;
import android.view.ContextMenu;
import android.view.ContextMenu.ContextMenuInfo;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView.AdapterContextMenuInfo;
import android.widget.BaseAdapter;
import android.widget.ListView;
import android.widget.TextView;

import com.andyidea.bean.Student;
import com.andyidea.db.DatabaseHelper;
import com.j256.ormlite.android.apptools.OrmLiteBaseActivity;
import com.j256.ormlite.dao.Dao;

public class StudentListActivity extends OrmLiteBaseActivity<DatabaseHelper> {
	
	private Context mContext;
	private ListView lvStudents;
	private Dao<Student,Integer> stuDao;
	private List<Student> students;
	private StudentsAdapter adapter;
	private Student mStudent;
	
	private final int MENU_VIEW = Menu.FIRST;
	private final int MENU_EDIT = Menu.FIRST+1;
	private final int MENU_DELETE = Menu.FIRST+2;
	
	private int position;
	
	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.students);
		mContext = getApplicationContext();
		
		lvStudents = (ListView)findViewById(R.id.stulist);
		registerForContextMenu(lvStudents);  //注册上下文菜单
		
		queryListViewItem();
	
		adapter = new StudentsAdapter(students);
		lvStudents.setAdapter(adapter);
		
	}

	@Override
	public void onCreateContextMenu(ContextMenu menu, View v,
			ContextMenuInfo menuInfo) {
		if(v == lvStudents)
			position = ((AdapterContextMenuInfo)menuInfo).position;
		
		menu.add(0,MENU_VIEW, 0, "查看");
		menu.add(0,MENU_EDIT, 0, "编辑");
		menu.add(0,MENU_DELETE,0,"删除");
		super.onCreateContextMenu(menu, v, menuInfo);
	}
	
	@Override
	public boolean onContextItemSelected(MenuItem item) {
		switch (item.getItemId()) {
		case MENU_VIEW:
			viewListViewItem(position);
			break;
		case MENU_EDIT:
			editListViewItem(position);
			break;
		case MENU_DELETE:
			deleteListViewItem(position);
			break;
		default:
			break;
		}
		return super.onContextItemSelected(item);
	}
	
	/**
	 * 查询记录项
	 */
	private void queryListViewItem(){
		try {
			stuDao = getHelper().getStudentDao();
			//查询所有的记录项
			students = stuDao.queryForAll();
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}
	
	/**
	 * 查看记录项
	 * @param position
	 */
	private void viewListViewItem(int position){
		mStudent = students.get(position);
		Intent intent = new Intent();
		intent.setClass(mContext, MainActivity.class);
		intent.putExtra("action", "viewone");
		intent.putExtra("entity", mStudent);
		startActivity(intent);
	}
	
	/**
	 * 编辑记录项
	 */
	private void editListViewItem(int position){
		mStudent = students.get(position);
		Intent intent = new Intent();
		intent.setClass(mContext, MainActivity.class);
		intent.putExtra("action", "edit");
		intent.putExtra("entity", mStudent);
		startActivity(intent);
	}
	
	/**
	 * 删除记录项
	 * @param position
	 */
	private void deleteListViewItem(int position){
		final int pos = position;
		AlertDialog.Builder builder2 = new AlertDialog.Builder(StudentListActivity.this);
		builder2.setIcon(android.R.drawable.ic_dialog_alert)
		        .setTitle("警告")
		        .setMessage("确定要删除该记录");
		builder2.setPositiveButton("确定", new DialogInterface.OnClickListener() {
			
			@Override
			public void onClick(DialogInterface dialog, int which) {
				Student mDelStudent = (Student)lvStudents.getAdapter().getItem(pos);
				try {
					stuDao.delete(mDelStudent); //删除记录
					queryListViewItem();
				} catch (SQLException e) {
					e.printStackTrace();
				}
				
			}
		});
		builder2.setNegativeButton("取消", new DialogInterface.OnClickListener() {
			
			@Override
			public void onClick(DialogInterface dialog, int which) {
				dialog.dismiss();
			}
		});
		builder2.show();
	}
	
	class StudentsAdapter extends BaseAdapter{
		
		private List<Student> listStu;
		
		public StudentsAdapter(List<Student> students){
			super();
			this.listStu = students;
		}

		@Override
		public int getCount() {
			return listStu.size();
		}

		@Override
		public Student getItem(int position) {
			return listStu.get(position);
		}

		@Override
		public long getItemId(int position) {
			return position;
		}

		@Override
		public View getView(int position, View convertView, ViewGroup parent) {
			ViewHolder holder;
			if(convertView == null){
				LayoutInflater mInflater = (LayoutInflater) mContext
						.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
				convertView = mInflater.inflate(R.layout.studentitem, null);
				holder = new ViewHolder();
				holder.tvNO = (TextView)convertView.findViewById(R.id.itemno);
				holder.tvName = (TextView)convertView.findViewById(R.id.itemname);
				holder.tvScore = (TextView)convertView.findViewById(R.id.itemscore);
				convertView.setTag(holder);
			}else{
				holder = (ViewHolder)convertView.getTag();
			}
			
			Student objStu = listStu.get(position);
			holder.tvNO.setText(objStu.getStuNO());
			holder.tvName.setText(objStu.getName());
			holder.tvScore.setText(String.valueOf(objStu.getScore()));
			
			return convertView;
		}
		
	}
	
	static class ViewHolder{
		TextView tvNO;
		TextView tvName;
		TextView tvScore;
	}

}

【6】成功运行程序的截图效果：