一.xml布局

<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" >
 
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="insert"
        android:text="插入" />
 
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="delete"
        android:text="删除" />
 
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="update"
        android:text="修改" />
 
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="select"
        android:text="查询" />
 
</LinearLayout>

public class MysqLiteOpenHelper extends sqliteOpenHelper {
		//创建数据库名字数字参数为版本号不可以为0
	public MysqLiteOpenHelper(Context context) {
		super(context,"1409L",null,1);
		// TODO Auto-generated constructor stub
	}
 
	@Override
	public void onCreate(sqliteDatabase db) {
		//创建表名和字段
		db.execsql("create table student(id integer primary key autoincrement,name varchar (20),sex varchar(6),age char(5)) ");
 
	}
		//版本更新运行下面的方法
	@Override
	public void onUpgrade(sqliteDatabase db,int oldVersion,int newVersion) {
		//如果需要改变哪一个表,要添加的字段,上边的版本号更改运行即可
<span style="white-space:pre">		</span>//db.execsql("alter table student add age varchar(6)");
 
	}
 
}

public class StudentDao {
 
	private sqliteDatabase sqliteDatabase;
	private MysqLiteOpenHelper helper;
 
	// 构造函数
	public StudentDao(Context context) {
 
		helper = new MysqLiteOpenHelper(context);
		
	}
	// 插入,通过方法传参的方式,插入数据
	public void insert(String name,String sex,String age) {
		//打开数据库
		sqliteDatabase = helper.getReadableDatabase();
		
		ContentValues values = new ContentValues();
 
		values.put("name",name);
		values.put("sex",sex);
		values.put("age",age);
 
		sqliteDatabase.insert("student",values);
		//关闭数据库
		sqliteDatabase.close();
	}
 
	// 删除
	public void delete(String name) {
		//打开数据库
 
		sqliteDatabase = helper.getReadableDatabase();
		
		sqliteDatabase.delete("student","name = ?",new String[] { name });
		
		//关闭数据库
		sqliteDatabase.close();
 
	}
 
	// 修改
	public void update(String newName,String oldName) {
		//打开数据库
 
		sqliteDatabase = helper.getReadableDatabase();
		
		ContentValues values = new ContentValues();
		values.put("name",newName);
		//把姓名(name)是oldName的数据,改成为姓名(name)是newName
		sqliteDatabase.update("student",values,new String[] {oldName});
 
		//关闭数据库
		sqliteDatabase.close();
	}
 
	// 查询
	public void select(String name) {
		
		
		//打开数据库
		sqliteDatabase = helper.getReadableDatabase();
		
		//通过name查询数据
		Cursor cursor = sqliteDatabase.query("student",new String[]{"name","sex","age"},new String[]{name},null);	
		
		while (cursor.moveToNext()) {
		//先得到列名的角标,在通过列名角标,获得该列名的数据
			String userName = cursor.getString(cursor.getColumnIndex("name"));
			String sex = cursor.getString(cursor.getColumnIndex("sex"));
			String age = cursor.getString(cursor.getColumnIndex("age"));
			
			System.out.println(userName+sex+age);
		}
		//关闭数据库
				sqliteDatabase.close();
	}
 
}

public class MainActivity extends ActionBarActivity {
 
 
	private StudentDao dao;
 
 
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
 
 
		dao = new StudentDao(this);
	}
 
 
	// 插入
	public void insert(View v) {
		
		dao.insert("张三","男","12");
	}
 
 
	// 删除
	public void delete(View v) {
		dao.delete("李四");
	}
 
 
	// 修改
	public void update(View v) {
		dao.update("李四","张三");
	}
 
 
	// 查询
	public void select(View v) {
		dao.select("李四");
	}
}