【黑马Android】(04)数据库的创建和sql语句增删改查/LinearLayout展示列表数据/ListView的使用和BaseAdater/内容提供者创建-阿里云开发者社区

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【黑马Android】(04)数据库的创建和sql语句增删改查/LinearLayout展示列表数据/ListView的使用和BaseAdater/内容提供者创建

简介: <p></p> <h2><strong><span style="font-family:黑体; font-size:16pt">数据库的创建和<span style="font-family:Arial">sql</span><span style="font-family:黑体">语句增删改查</span></span><span style="font-family:黑体; fon

数据库的创建和sql语句增删改查


1. 加载驱动.

2. 连接数据库.

3. 操作数据库.

 

创建表:

create table person(

_id integer primary key,

name varchar(20),

age integer

);

 

添加: insert into person(name, age) values('lisi', 19);

 

删除: delete from person where _id = 1;

 

修改: update person set name = '李四' where name = '王五';

 

查询所有: select * from person;

 

查询单条: select * from person where name = 'zhangsan';

 

SQLiteExpert3, pc上的工具软件。

package com.itheima28.sqlitedemo.dao;

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

import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;

import com.itheima28.sqlitedemo.db.PersonSQLiteOpenHelper;
import com.itheima28.sqlitedemo.entities.Person;

public class PersonDao {

	private PersonSQLiteOpenHelper mOpenHelper;	// 数据库的帮助类对象

	public PersonDao(Context context) {
		mOpenHelper = new PersonSQLiteOpenHelper(context);
	}
	
	/**
	 * 添加到person表一条数据
	 * @param person
	 */
	public void insert(Person person) {
		SQLiteDatabase db = mOpenHelper.getWritableDatabase();
		if(db.isOpen()) {	// 如果数据库打开, 执行添加的操作
			
			// 执行添加到数据库的操作
			db.execSQL("insert into person(name, age) values(?, ?);", new Object[]{person.getName(), person.getAge()});
			
			db.close();	// 数据库关闭
		}
	}
	
	/**
	 * 更据id删除记录
	 * @param id
	 */
	public void delete(int id) {
		SQLiteDatabase db = mOpenHelper.getWritableDatabase();	// 获得可写的数据库对象
		if(db.isOpen()) {	// 如果数据库打开, 执行添加的操作
			
			db.execSQL("delete from person where _id = ?;", new Integer[]{id});
			
			db.close();	// 数据库关闭
		}
	}
	

	/**
	 * 根据id找到记录, 并且修改姓名
	 * @param id
	 * @param name
	 */
	public void update(int id, String name) {
		SQLiteDatabase db = mOpenHelper.getWritableDatabase();
		if(db.isOpen()) {	// 如果数据库打开, 执行添加的操作
			
			db.execSQL("update person set name = ? where _id = ?;", new Object[]{name, id});
			
			db.close();	// 数据库关闭
		}
	}
	
	public List<Person> queryAll() {
		SQLiteDatabase db = mOpenHelper.getReadableDatabase();	// 获得一个只读的数据库对象
		if(db.isOpen()) {
			
			Cursor cursor = db.rawQuery("select _id, name, age from person;", null);
			
			if(cursor != null && cursor.getCount() > 0) {
				List<Person> personList = new ArrayList<Person>();
				int id;
				String name;
				int age;
				while(cursor.moveToNext()) {
					id = cursor.getInt(0);	// 取第0列的数据 id
					name = cursor.getString(1);	// 取姓名
					age = cursor.getInt(2);		// 取年龄
					personList.add(new Person(id, name, age));
				}

				db.close();
				return personList;
			}
			db.close();
		}
		return null;
	}
	
	/**
	 * 根据id查询人
	 * @param id
	 * @return
	 */
	public Person queryItem(int id) {
		SQLiteDatabase db = mOpenHelper.getReadableDatabase();	// 获得一个只读的数据库对象
		if(db.isOpen()) {
			Cursor cursor = db.rawQuery("select _id, name, age from person where _id = ?;", new String[]{id + ""});
			if(cursor != null && cursor.moveToFirst()) {
				int _id = cursor.getInt(0);
				String name = cursor.getString(1);
				int age = cursor.getInt(2);
				db.close();
				return new Person(_id, name, age);
			}
			db.close();
		}
		return null;
	}
}

package com.itheima28.sqlitedemo.db;

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

/**
 * @author andong
 * 数据库帮助类, 用于创建和管理数据库的.
 */
public class PersonSQLiteOpenHelper extends SQLiteOpenHelper {

	private static final String TAG = "PersonSQLiteOpenHelper";

	/**
	 * 数据库的构造函数
	 * @param context
	 * 
	 * name 数据库名称
	 * factory 游标工程
	 * version 数据库的版本号 不可以小于1
	 */
	public PersonSQLiteOpenHelper(Context context) {
		super(context, "itheima28.db", null, 2);
	}

	/**
	 * 数据库第一次创建时回调此方法.
	 * 初始化一些表
	 */
	@Override
	public void onCreate(SQLiteDatabase db) {

		// 操作数据库
		String sql = "create table person(_id integer primary key, name varchar(20), age integer);";
		db.execSQL(sql);		// 创建person表
	}

	/**
	 * 数据库的版本号更新时回调此方法,
	 * 更新数据库的内容(删除表, 添加表, 修改表)
	 */
	@Override
	public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

		if(oldVersion == 1 && newVersion == 2) {
			Log.i(TAG, "数据库更新啦");
			// 在person表中添加一个余额列balance
			db.execSQL("alter table person add balance integer;");
		}
	}
}

package com.itheima28.sqlitedemo.entities;

public class Person {

	private int id;
	private String name;
	private int age;
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	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 Person() {
		super();
		// TODO Auto-generated constructor stub
	}
	public Person(int id, String name, int age) {
		super();
		this.id = id;
		this.name = name;
		this.age = age;
	}
	@Override
	public String toString() {
		return "Person [id=" + id + ", name=" + name + ", age=" + age + "]";
	}
}

package com.itheima28.sqlitedemo.test;

import java.util.List;

import com.itheima28.sqlitedemo.dao.PersonDao;
import com.itheima28.sqlitedemo.db.PersonSQLiteOpenHelper;
import com.itheima28.sqlitedemo.entities.Person;

import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.test.AndroidTestCase;
import android.util.Log;

public class TestCase extends AndroidTestCase {

	private static final String TAG = "TestCase";

	public void test() {
		// 数据库什么时候创建
		PersonSQLiteOpenHelper openHelper = new PersonSQLiteOpenHelper(getContext());
		
		// 第一次连接数据库时创建数据库文件. onCreate会被调用
		openHelper.getReadableDatabase();
	}
	
	public void testInsert() {
		PersonDao dao = new PersonDao(getContext());
		
		dao.insert(new Person(0, "冠希", 28));
	}
	
	public void testDelete() {
		PersonDao dao = new PersonDao(getContext());
		dao.delete(1);
	}

	public void testUpdate() {
		PersonDao dao = new PersonDao(getContext());
		dao.update(3, "凤姐");
	}

	public void testQueryAll() {
		PersonDao dao = new PersonDao(getContext());
		List<Person> personList = dao.queryAll();
		
		for (Person person : personList) {
			Log.i(TAG, person.toString());
		}
	}

	public void testQueryItem() {
		PersonDao dao = new PersonDao(getContext());
		Person person = dao.queryItem(4);
		Log.i(TAG, person.toString());
	}
	
	public void testTransaction() {
		PersonSQLiteOpenHelper openHelper = new PersonSQLiteOpenHelper(getContext());
		SQLiteDatabase db = openHelper.getWritableDatabase();
		
		if(db.isOpen()) {
			
			try {
				// 开启事务
				db.beginTransaction();
				
				// 1. 从张三账户中扣1000块钱
				db.execSQL("update person set balance = balance - 1000 where name = 'zhangsan';");
				
				// ATM机, 挂掉了.
				// int result = 10 / 0;
				
				// 2. 向李四账户中加1000块钱
				db.execSQL("update person set balance = balance + 1000 where name = 'lisi';");
				
				// 标记事务成功
				db.setTransactionSuccessful();
			} finally {
				// 停止事务
				db.endTransaction();
			}
			db.close();
		}
	}
	
	public void testTransactionInsert() {
		PersonSQLiteOpenHelper openHelper = new PersonSQLiteOpenHelper(getContext());
		SQLiteDatabase db = openHelper.getWritableDatabase();
		
		if(db.isOpen()) {
			
			// 1. 记住当前的时间
			long start = System.currentTimeMillis();
			
			// 2. 开始添加数据
			try {
				db.beginTransaction();
				for (int i = 0; i < 10000; i++) {
					db.execSQL("insert into person(name, age, balance) values('wang" + i + "', " + (10 + i) + ", " + (10000 + i) + ")");
				}
				db.setTransactionSuccessful();
			} finally {
				db.endTransaction();
			}
			
			// 3. 记住结束时间, 计算耗时时间
			long end = System.currentTimeMillis();
			
			long diff = end - start;
			Log.i(TAG, "耗时: " + diff + "毫秒");
			
			db.close();
		}
	}
}
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.itheima28.sqlitedemo"
    android:versionCode="1"
    android:versionName="1.0" >

    <instrumentation
        android:name="android.test.InstrumentationTestRunner"
        android:targetPackage="com.itheima28.sqlitedemo" >
    </instrumentation>

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="17" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <uses-library android:name="android.test.runner" />

        <activity
            android:name="com.itheima28.sqlitedemo.MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

使用api方式查询数据库和sqlite3工具


adb shell


package com.itheima28.sqlitedemo.dao;

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

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

import com.itheima28.sqlitedemo.db.PersonSQLiteOpenHelper;
import com.itheima28.sqlitedemo.entities.Person;

public class PersonDao2 {

	private static final String TAG = "PersonDao2";
	private PersonSQLiteOpenHelper mOpenHelper;	// 数据库的帮助类对象

	public PersonDao2(Context context) {
		mOpenHelper = new PersonSQLiteOpenHelper(context);
	}
	
	/**
	 * 添加到person表一条数据
	 * @param person
	 */
	public void insert(Person person) {
		SQLiteDatabase db = mOpenHelper.getWritableDatabase();
		if(db.isOpen()) {	// 如果数据库打开, 执行添加的操作
			
			ContentValues values = new ContentValues();
			values.put("name", person.getName());		// key作为要存储的列名, value对象列的值
			values.put("age", person.getAge());
			long id = db.insert("person", "name", values);
			Log.i(TAG, "id: " + id);
			
			db.close();	// 数据库关闭
		}
	}
	
	/**
	 * 更据id删除记录
	 * @param id
	 */
	public void delete(int id) {
		SQLiteDatabase db = mOpenHelper.getWritableDatabase();	// 获得可写的数据库对象
		if(db.isOpen()) {	// 如果数据库打开, 执行添加的操作
			
			String whereClause = "_id = ?";
			String[] whereArgs = {id + ""};
			int count = db.delete("person", whereClause, whereArgs);
			Log.i(TAG, "删除了: " + count + "行");
			db.close();	// 数据库关闭
		}
	}
	

	/**
	 * 根据id找到记录, 并且修改姓名
	 * @param id
	 * @param name
	 */
	public void update(int id, String name) {
		SQLiteDatabase db = mOpenHelper.getWritableDatabase();
		if(db.isOpen()) {	// 如果数据库打开, 执行添加的操作
			ContentValues values = new ContentValues();
			values.put("name", name);
			
			int count  = db.update("person", values, "_id = ?", new String[]{id + ""});

			Log.i(TAG, "修改了: " + count + "行");
			
			db.close();	// 数据库关闭
		}
	}
	
	public List<Person> queryAll() {
		SQLiteDatabase db = mOpenHelper.getReadableDatabase();	// 获得一个只读的数据库对象
		if(db.isOpen()) {
			String[] columns = {"_id", "name", "age"};	// 需要的列
			String selection = null;	// 选择条件, 给null查询所有
			String[] selectionArgs = null;	// 选择条件的参数, 会把选择条件中的? 替换成数据中的值
			String groupBy = null;	// 分组语句  group by name
			String having = null;	// 过滤语句
			String orderBy = null;	// 排序
			
			Cursor cursor = db.query("person", columns, selection, selectionArgs, groupBy, having, orderBy);
			
			int id;
			String name;
			int age;
			if(cursor != null && cursor.getCount() > 0) {
				List<Person> personList = new ArrayList<Person>();
				
				while(cursor.moveToNext()) {	// 向下移一位, 知道最后一位, 不可以往下移动了, 停止.
					id = cursor.getInt(0);
					name = cursor.getString(1);
					age = cursor.getInt(2);
					
					personList.add(new Person(id, name, age));
				}
				
				db.close();
				return personList;
			}
			db.close();
		}
		return null;
	}
	
	/**
	 * 根据id查询人
	 * @param id
	 * @return
	 */
	public Person queryItem(int id) {
		SQLiteDatabase db = mOpenHelper.getReadableDatabase();	// 获得一个只读的数据库对象
		if(db.isOpen()) {
			String[] columns = {"_id", "name", "age"};	// 需要的列
			String selection = "_id = ?";	// 选择条件, 给null查询所有
			String[] selectionArgs = {id + ""};	// 选择条件的参数, 会把选择条件中的? 替换成数据中的值
			String groupBy = null;	// 分组语句  group by name
			String having = null;	// 过滤语句
			String orderBy = null;	// 排序
			
			Cursor cursor = db.query("person", columns, selection, selectionArgs, groupBy, having, orderBy);
			
			if(cursor != null && cursor.moveToFirst()) {		// cursor对象不为null, 并且可以移动到第一行
				int _id = cursor.getInt(0);
				String name = cursor.getString(1);
				int age = cursor.getInt(2);
				
				db.close();
				return new Person(_id, name, age);
			}
			db.close();
		}
		return null;
	}
}

package com.itheima28.sqlitedemo.test;

import java.util.List;

import android.test.AndroidTestCase;
import android.util.Log;

import com.itheima28.sqlitedemo.dao.PersonDao2;
import com.itheima28.sqlitedemo.db.PersonSQLiteOpenHelper;
import com.itheima28.sqlitedemo.entities.Person;

public class TestCase2 extends AndroidTestCase {

	private static final String TAG = "TestCase";

	public void test() {
		// 数据库什么时候创建
		PersonSQLiteOpenHelper openHelper = new PersonSQLiteOpenHelper(getContext());
		
		// 第一次连接数据库时创建数据库文件. onCreate会被调用
		openHelper.getReadableDatabase();
	}
	
	public void testInsert() {
		PersonDao2 dao = new PersonDao2(getContext());
		dao.insert(new Person(0, "zhouqi", 88));
	}
	
	public void testDelete() {
		PersonDao2 dao = new PersonDao2(getContext());
		dao.delete(8);
	}

	public void testUpdate() {
		PersonDao2 dao = new PersonDao2(getContext());
		dao.update(3, "fengjie");
	}

	public void testQueryAll() {
		PersonDao2 dao = new PersonDao2(getContext());
		List<Person> personList = dao.queryAll();
		
		for (Person person : personList) {
			Log.i(TAG, person.toString());
		}
	}

	public void testQueryItem() {
		PersonDao2 dao = new PersonDao2(getContext());
		Person person = dao.queryItem(4);
		Log.i(TAG, person.toString());
	}
}

事务的操作

事务:

update person set balance = balance - 100 where name = 'lisi';

update person set balance = balance + 100 where name = 'zhangsan';

 

// 开启事务

db.beginTransaction();

 

// 标记事务成功

db.setTransactionSuccessful();

 

// 停止事务

db.endTransaction();

	public void testTransaction() {
		PersonSQLiteOpenHelper openHelper = new PersonSQLiteOpenHelper(getContext());
		SQLiteDatabase db = openHelper.getWritableDatabase();
		
		if(db.isOpen()) {
			
			try {
				// 开启事务
				db.beginTransaction();
				
				// 1. 从张三账户中扣1000块钱
				db.execSQL("update person set balance = balance - 1000 where name = 'zhangsan';");
				
				// ATM机, 挂掉了.
				// int result = 10 / 0;
				
				// 2. 向李四账户中加1000块钱
				db.execSQL("update person set balance = balance + 1000 where name = 'lisi';");
				
				// 标记事务成功
				db.setTransactionSuccessful();
			} finally {
				// 停止事务
				db.endTransaction();
			}
			db.close();
		}
	}
	
	public void testTransactionInsert() {
		PersonSQLiteOpenHelper openHelper = new PersonSQLiteOpenHelper(getContext());
		SQLiteDatabase db = openHelper.getWritableDatabase();
		
		if(db.isOpen()) {
			
			// 1. 记住当前的时间
			long start = System.currentTimeMillis();
			
			// 2. 开始添加数据
			try {
				db.beginTransaction();
				for (int i = 0; i < 10000; i++) {
					db.execSQL("insert into person(name, age, balance) values('wang" + i + "', " + (10 + i) + ", " + (10000 + i) + ")");
				}
				db.setTransactionSuccessful();
			} finally {
				db.endTransaction();
			}
			
			// 3. 记住结束时间, 计算耗时时间
			long end = System.currentTimeMillis();
			
			long diff = end - start;
			Log.i(TAG, "耗时: " + diff + "毫秒");
			
			db.close();
		}
	}

LinearLayout展示列表数据

<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <LinearLayout
        android:id="@+id/ll_list"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical" >
    </LinearLayout>

</ScrollView>

package com.itheima28.sqlitedemo;

import java.util.List;

import com.itheima28.sqlitedemo.dao.PersonDao;
import com.itheima28.sqlitedemo.entities.Person;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.widget.LinearLayout;
import android.widget.TextView;

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        LinearLayout llList = (LinearLayout) findViewById(R.id.ll_list);
        
        PersonDao dao = new PersonDao(this);
        List<Person> personList = dao.queryAll();
        
        if(personList != null) {
	        TextView tv;
	        for (Person person : personList) {
				// 向线性布局中添加一个textview
	        	tv = new TextView(this);
	        	tv.setText(person.toString());
	        	tv.setTextSize(18);
	        	
	        	llList.addView(tv);
			}
        }
    }


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

ListView的使用和BaseAdater

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <ListView
        android:id="@+id/listview"
        android:layout_width="match_parent"
        android:layout_height="match_parent" >
    </ListView>

</LinearLayout>

package com.itheima28.sqlitedemo;

import java.util.List;

import com.itheima28.sqlitedemo.dao.PersonDao;
import com.itheima28.sqlitedemo.entities.Person;

import android.os.Bundle;
import android.app.Activity;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.TextView;

public class MainActivity extends Activity {

    private List<Person> personList;

	@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        ListView mListView = (ListView) findViewById(R.id.listview);
        
        PersonDao dao = new PersonDao(this);
        personList = dao.queryAll();
        
        // 把view层对象ListView和控制器BaseAdapter关联起来
        mListView.setAdapter(new MyAdapter());
    }

    /**
     * @author andong
     * 数据适配器
     */
    class MyAdapter extends BaseAdapter {

    	private static final String TAG = "MyAdapter";

		/**
    	 * 定义ListView的数据的长度
    	 */
		@Override
		public int getCount() {
			return personList.size();
		}

		@Override
		public Object getItem(int position) {
			// TODO Auto-generated method stub
			return null;
		}

		@Override
		public long getItemId(int position) {
			// TODO Auto-generated method stub
			return 0;
		}

		/**
		 * 此方法返回的是ListView的列表中某一行的View对象
		 * position 当前返回的view的索引位置
		 * convertView 缓存对象
		 * parent 就是ListView对象
		 */
		@Override
		public View getView(int position, View convertView, ViewGroup parent) {					
			TextView tv = null;			
			
			if(convertView != null) {		// 判断缓存对象是否为null,  不为null时已经缓存了对象
				Log.i(TAG, "getView: 复用缓存" + position);
				tv = (TextView) convertView;
			} else {	// 等于null, 说明第一次显示, 新创建
				Log.i(TAG, "getView: 新建" + position);
				tv = new TextView(MainActivity.this);
			}
			
			tv.setTextSize(25);
			
			Person person = personList.get(position); // 获得指定位置的数据, 进行对TextView的绑定
			
			tv.setText(person.toString());
			
			return tv;
		}
    	
    }
}
package com.itheima28.sqlitedemo;

import java.util.List;

import com.itheima28.sqlitedemo.dao.PersonDao;
import com.itheima28.sqlitedemo.entities.Person;

import android.os.Bundle;
import android.app.Activity;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.TextView;

public class MainActivity2 extends Activity {

    private List<Person> personList;

	@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        ListView mListView = (ListView) findViewById(R.id.listview);
        
        PersonDao dao = new PersonDao(this);
        personList = dao.queryAll();
        
        // 把view层对象ListView和控制器BaseAdapter关联起来
        mListView.setAdapter(new MyAdapter());
    }

    /**
     * @author andong
     * 数据适配器
     */
    class MyAdapter extends BaseAdapter {

    	private static final String TAG = "MyAdapter";

		/**
    	 * 定义ListView的数据的长度
    	 */
		@Override
		public int getCount() {
			return personList.size();
		}

		@Override
		public Object getItem(int position) {
			// TODO Auto-generated method stub
			return null;
		}

		@Override
		public long getItemId(int position) {
			// TODO Auto-generated method stub
			return 0;
		}

		/**
		 * 此方法返回的是ListView的列表中某一行的View对象
		 * position 当前返回的view的索引位置
		 * convertView 缓存对象
		 * parent 就是ListView对象
		 */
		@Override
		public View getView(int position, View convertView, ViewGroup parent) {
			View view = null;
			
			if(convertView == null) {
				// 布局填充器对象, 用于把xml布局转换成view对象
				LayoutInflater inflater = MainActivity2.this.getLayoutInflater();
				view = inflater.inflate(R.layout.listview_item, null);
			} else {
				view = convertView;
			}
			
			// 给view中的姓名和年龄赋值
			TextView tvName = (TextView) view.findViewById(R.id.tv_listview_item_name);
			TextView tvAge = (TextView) view.findViewById(R.id.tv_listview_item_age);
			
			Person person = personList.get(position);
			
			tvName.setText("姓名: " + person.getName());
			tvAge.setText("年龄: " + person.getAge());
			return view;
		}
    	
    }
}

listview_item.xml

<?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="wrap_content"
    android:orientation="horizontal"
    android:padding="10dip" >

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/f078" />

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginLeft="10dip"
        android:orientation="vertical" >

        <TextView
            android:id="@+id/tv_listview_item_name"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="张三" />

        <TextView
            android:id="@+id/tv_listview_item_age"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="5dip"
            android:textColor="#FF0000"
            android:text="35" />
    </LinearLayout>

</LinearLayout>

其他两种绑定ListView数据的方式

<RelativeLayout 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"
    tools:context=".MainActivity" >

    <ListView
        android:id="@+id/listview"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

</RelativeLayout>

listview_item.xml

<?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="wrap_content"
    android:gravity="center_vertical"
    android:orientation="horizontal"
    android:padding="10dip" >

    <ImageView
        android:id="@+id/iv_icon"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/f007" />

    <TextView
        android:id="@+id/tv_name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="10dip"
        android:text="张三"
        android:textColor="#FF0000"
        android:textSize="23sp" />

</LinearLayout>
package com.itheima28.simpleadapterdemo;

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

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;

public class MainActivity extends Activity {

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		
		ListView mListView = (ListView) findViewById(R.id.listview);
		
		List<Map<String, Object>> data = new ArrayList<Map<String,Object>>();
		
		Map<String, Object> map = new HashMap<String, Object>();
		map.put("name", "张三1");
		map.put("icon", R.drawable.f007);
		data.add(map);
		
		map = new HashMap<String, Object>();
		map.put("name", "张三2");
		map.put("icon", R.drawable.f007);
		data.add(map);

		map = new HashMap<String, Object>();
		map.put("name", "张三3");
		map.put("icon", R.drawable.f007);
		data.add(map);

		map = new HashMap<String, Object>();
		map.put("name", "张三4");
		map.put("icon", R.drawable.f007);
		data.add(map);

		map = new HashMap<String, Object>();
		map.put("name", "张三5");
		map.put("icon", R.drawable.f007);
		data.add(map);
		
		SimpleAdapter adapter = new SimpleAdapter(
				this, // 上下文
				data, // listView绑定的数据
				R.layout.listview_item, // listview的子条目的布局的id
				new String[]{"name", "icon"}, 	// data数据中的map集合里的key
				new int[]{R.id.tv_name, R.id.iv_icon}); // resource 中的id
		
		mListView.setAdapter(adapter);
	}

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

}

内容提供者创建

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.itheima28.sqlitedemo"
    android:versionCode="1"
    android:versionName="1.0" >

    <instrumentation
        android:name="android.test.InstrumentationTestRunner"
        android:targetPackage="com.itheima28.sqlitedemo" >
    </instrumentation>
    
    <permission android:name="aa.bb.cc.read" ></permission>
    <permission android:name="aa.bb.cc.write" ></permission>

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="17" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <uses-library android:name="android.test.runner" />

        <activity
            android:name="com.itheima28.sqlitedemo.MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <provider
            android:name=".providers.PersonContentProvider"
            android:authorities="com.itheima28.sqlitedemo.providers.PersonContentProvider"
            android:readPermission="aa.bb.cc.read"
            android:writePermission="aa.bb.cc.write" >
        </provider>
    </application>

</manifest>
package com.itheima28.sqlitedemo.providers;

import com.itheima28.sqlitedemo.db.PersonSQLiteOpenHelper;

import android.content.ContentProvider;
import android.content.ContentUris;
import android.content.ContentValues;
import android.content.UriMatcher;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.net.Uri;

public class PersonContentProvider extends ContentProvider {
	
	private static final String AUTHORITY = "com.itheima28.sqlitedemo.providers.PersonContentProvider";
	private static final int PRESON_INSERT_CODE = 0;	// 操作person表添加的操作的uri匹配码
	private static final int PERSON_DELETE_CODE = 1;
	private static final int PERSON_UPDATE_CODE = 2;
	private static final int PERSON_QUERY_ALL_CODE = 3;
	private static final int PERSON_QUERY_ITEM_CODE = 4;
	
	private static UriMatcher uriMatcher;
	private PersonSQLiteOpenHelper mOpenHelper;		// person表的数据库帮助对象
	
	static {
		uriMatcher = new UriMatcher(UriMatcher.NO_MATCH);
		
		// 添加一些uri(分机号)
		
		// content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/insert
		uriMatcher.addURI(AUTHORITY, "person/insert", PRESON_INSERT_CODE);
		
		// content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/delete
		uriMatcher.addURI(AUTHORITY, "person/delete", PERSON_DELETE_CODE);

		// content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/update
		uriMatcher.addURI(AUTHORITY, "person/update", PERSON_UPDATE_CODE);
		
		// content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/queryAll
		uriMatcher.addURI(AUTHORITY, "person/queryAll", PERSON_QUERY_ALL_CODE);
		
		// content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/query/#
		uriMatcher.addURI(AUTHORITY, "person/query/#", PERSON_QUERY_ITEM_CODE);
	}

	@Override
	public boolean onCreate() {
		mOpenHelper = new PersonSQLiteOpenHelper(getContext());
		return true;
	}

	@Override
	public Cursor query(Uri uri, String[] projection, String selection,
			String[] selectionArgs, String sortOrder) {
		SQLiteDatabase db = mOpenHelper.getReadableDatabase();
		switch (uriMatcher.match(uri)) {
		case PERSON_QUERY_ALL_CODE:  // 查询所有人的uri
			if(db.isOpen()) {
				Cursor cursor = db.query("person", projection, selection, selectionArgs, null, null, sortOrder);
				return cursor;
				// db.close(); 返回cursor结果集时, 不可以关闭数据库
			}
			break;
		case PERSON_QUERY_ITEM_CODE:		// 查询的是单条数据, uri末尾出有一个id
			if(db.isOpen()) {
				
				long id = ContentUris.parseId(uri);
				
				Cursor cursor = db.query("person", projection, "_id = ?", new String[]{id + ""}, null, null, sortOrder);

				return cursor;
			}
			break;
		default:
			throw new IllegalArgumentException("uri不匹配: " + uri);
		}
		return null;
	}

	@Override
	public String getType(Uri uri) {
		switch (uriMatcher.match(uri)) {
		case PERSON_QUERY_ALL_CODE: // 返回多条的MIME-type
			return "vnd.android.cursor.dir/person";
		case PERSON_QUERY_ITEM_CODE: // 返回单条的MIME-TYPE
			return "vnd.android.cursor.item/person";
		default:
			break;
		}
		return null;
	}

	@Override
	public Uri insert(Uri uri, ContentValues values) {
		
		switch (uriMatcher.match(uri)) {
		case PRESON_INSERT_CODE:	// 添加人到person表中
			SQLiteDatabase db = mOpenHelper.getWritableDatabase();
			
			if(db.isOpen()) {
				
				long id = db.insert("person", null, values);
				
				db.close();
				
				return ContentUris.withAppendedId(uri, id);
			}
			break;
		default:
			throw new IllegalArgumentException("uri不匹配: " + uri);
		}
		return null;
	}

	@Override
	public int delete(Uri uri, String selection, String[] selectionArgs) {
		switch (uriMatcher.match(uri)) {
		case PERSON_DELETE_CODE:	// 在person表中删除数据的操作
			SQLiteDatabase db = mOpenHelper.getWritableDatabase();
			if(db.isOpen()) {
				int count = db.delete("person", selection, selectionArgs);
				db.close();
				return count;
			}
			break;
		default:
			throw new IllegalArgumentException("uri不匹配: " + uri);
		}
		return 0;
	}

	@Override
	public int update(Uri uri, ContentValues values, String selection,
			String[] selectionArgs) {
		switch (uriMatcher.match(uri)) {
		case PERSON_UPDATE_CODE: // 更新person表的操作
			SQLiteDatabase db = mOpenHelper.getWritableDatabase();
			if(db.isOpen()) {
				int count = db.update("person", values, selection, selectionArgs);
				db.close();
				return count;
			}
			break;
		default:
			throw new IllegalArgumentException("uri不匹配: " + uri);
		}
		return 0;
	}

}

内容提供者访问和权限

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.itheima28.othercontentprovider"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="17" />

    <instrumentation
        android:name="android.test.InstrumentationTestRunner"
        android:targetPackage="com.itheima28.othercontentprovider" >
    </instrumentation>
    <uses-permission android:name="aa.bb.cc.read"/>
    <uses-permission android:name="aa.bb.cc.write"/>

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <uses-library android:name="android.test.runner" />

        <activity
            android:name="com.itheima28.othercontentprovider.MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>
package com.itheima28.othercontentprovider;

import android.content.ContentResolver;
import android.content.ContentUris;
import android.content.ContentValues;
import android.database.Cursor;
import android.net.Uri;
import android.test.AndroidTestCase;
import android.util.Log;

public class TextCase extends AndroidTestCase {

	private static final String TAG = "TextCase";

	public void testInsert() {
		Uri uri = Uri.parse("content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/insert");
		
		// 内容提供者访问对象
		ContentResolver resolver = getContext().getContentResolver();
		
		ContentValues values = new ContentValues();
		values.put("name", "fengjie");
		values.put("age", 90);
		
		uri = resolver.insert(uri, values);
		Log.i(TAG, "uri: " + uri);
		long id = ContentUris.parseId(uri);
		Log.i(TAG, "添加到: " + id);
	}
	
	public void testDelete() {
		Uri uri = Uri.parse("content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/delete");
		
		// 内容提供者访问对象
		ContentResolver resolver = getContext().getContentResolver();
		
		String where = "_id = ?";
		String[] selectionArgs = {"21"};
		int count = resolver.delete(uri, where, selectionArgs);
		Log.i(TAG, "删除行: " + count);
	}
	
	public void testUpdate() {
		Uri uri = Uri.parse("content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/update");
		
		// 内容提供者访问对象
		ContentResolver resolver = getContext().getContentResolver();
		
		ContentValues values = new ContentValues();
		values.put("name", "lisi");
		
		int count = resolver.update(uri, values, "_id = ?", new String[]{"20"});
		Log.i(TAG, "更新行: " + count);
	}
	
	public void testQueryAll() {
		Uri uri = Uri.parse("content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/queryAll");
		
		// 内容提供者访问对象
		ContentResolver resolver = getContext().getContentResolver();
		
		Cursor cursor = resolver.query(uri, new String[]{"_id", "name", "age"}, null, null, "_id desc");
		
		if(cursor != null && cursor.getCount() > 0) {
			
			int id;
			String name;
			int age;
			while(cursor.moveToNext()) {
				id = cursor.getInt(0);
				name = cursor.getString(1);
				age = cursor.getInt(2);
				Log.i(TAG, "id: " + id + ", name: " + name + ", age: " + age);
			}
			cursor.close();
		}
	}
	
	public void testQuerySingleItem() {
		Uri uri = Uri.parse("content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/query/#");
		
		// 在uri的末尾添加一个id content://com.itheima28.sqlitedemo.providers.PersonContentProvider/person/query/20
		uri = ContentUris.withAppendedId(uri, 20);
		
		// 内容提供者访问对象
		ContentResolver resolver = getContext().getContentResolver();
		
		Cursor cursor = resolver.query(uri, new String[]{"_id", "name", "age"}, null, null, null);
		
		if(cursor != null && cursor.moveToFirst()) {
			int id = cursor.getInt(0);
			String name = cursor.getString(1);
			int age = cursor.getInt(2);
			cursor.close();
			Log.i(TAG, "id: " + id + ", name: " + name + ", age: " + age);
		}
	}
}


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