• [转载]创建数据库与完成数据添删改查——第二种写法


    <?xml version="1.0" encoding="utf-8"?>
    <manifest xmlns:android="http://schemas.android.com/apk/res/android"
        package="cn.itcast.db"
        android:versionCode="1"
        android:versionName="1.0" >
    
        <uses-sdk android:minSdkVersion="8" />
    
        <application
            android:icon="@drawable/ic_launcher"
            android:label="@string/app_name" >
            <activity
                android:name=".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>
            <uses-library android:name="android.test.runner"/>
        </application>
    
        <instrumentation android:name="android.test.InstrumentationTestRunner"
            android:targetPackage="cn.itcast.db" android:label="Tests for My App"></instrumentation>
        
    </manifest>
    package cn.itcast.db;
    
    import android.app.Activity;
    import android.os.Bundle;
    
    public class MainActivity extends Activity {
        /** Called when the activity is first created. */
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
        }
        
        //在Android平台上,集成了一个嵌入式关系型数据库——SQLite
        //SQLite3支持NULL、INTEGER、REAL(浮点数字)、TEXT(字符串文本)和BLOB(二进制对象)数据类型
        //虽然它支持的类型只有5种,但实际上sqlite3也接受varchar(n)、char(n)、decimal(p, s)等数据
        //只不过在运行或保存时会转成对应的五种数据类型
        //SQLite最大的特点是你可以把各种类型的数据保存到任何字段中,而不用关心字段声明的数据类型是什么
    }
    package cn.itcast.domain;
    
    public class Person {
            private Integer id;
            private String name;
            private String phone;
                    
            public Person(String name, String phone){
                    this.name = name;
                    this.phone = phone;
            }
            
            public Person(Integer id, String name, String phone){
                    this.id = id;
                    this.name = name;
                    this.phone = phone;
            }
            
            public Integer getId() {
                    return id;
            }
            public void setId(Integer id) {
                    this.id = id;
            }
            public String getName() {
                    return name;
            }
            public void setName(String name) {
                    this.name = name;
            }
            public String getPhone() {
                    return phone;
            }
            public void setPhone(String phone) {
                    this.phone = phone;
            }        
    }
    
    package cn.itcast.service;
    
    import android.content.Context;
    import android.database.sqlite.SQLiteDatabase;
    import android.database.sqlite.SQLiteOpenHelper;
    
    public class DBOpenHelper extends SQLiteOpenHelper{
            private static final int VERSION = 2; //数据库版本
            
            public DBOpenHelper(Context context){
                    super(context, "itcast.db", null, VERSION); //<包>/database/
            }
    
            @Override
            public void onCreate(SQLiteDatabase db) { //是在数据库第一次被创建的时候调用的
                    db.execSQL("CREATE TABLE person(personId integer primary key autoincrement, " +
                                    "name varchar(20))");                
            }
    
            @Override
            public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { //数据库版本号发生改变的时候调用的
                    db.execSQL("ALTER TABLE person ADD phone VARCHAR(12) NULL");
            }
    }
    

    package cn.itcast.test;
    
    import java.util.List;
    
    import android.test.AndroidTestCase;
    import android.util.Log;
    import cn.itcast.domain.Person;
    import cn.itcast.service.DBOpenHelper;
    import cn.itcast.service.OtherPersonService;
    import cn.itcast.service.PersonService;
    
    public class OtherPersonServiceTest extends AndroidTestCase{
            private static final String TAG = "OtherPersonServiceTest";
            //不可以放这里
            //原因,先实例化测试类才会实例化类,而实例化类之后才使用全局变量,所以在调用过程中
            //service = null
    //        PersonService service = new PersonService(this.getContext());
    
            public void testCreateDB() throws Exception{
                    DBOpenHelper dbOpenHelper = new DBOpenHelper(getContext());
                    dbOpenHelper.getWritableDatabase();
            }        
    
            public void testSave() throws Exception{
                    OtherPersonService service = new OtherPersonService(this.getContext());
                    for(int i = 0; i < 20; i++){
                            Person person = new Person("zhangsan", "123456");
                            service.save(person);
                    }
            }
    
            public void testDelete() throws Exception{
                    OtherPersonService service = new OtherPersonService(this.getContext());
                    service.delete(21);
            }
    
            public void testUpdate() throws Exception{
                    OtherPersonService service = new OtherPersonService(this.getContext());
                    Person person = service.find(1);
                    person.setName("zhangxiaoxiao");
                    service.update(person);
    
            }
    
            public void testFind() throws Exception{
                    OtherPersonService service = new OtherPersonService(this.getContext());
                    Person person = service.find(1);
                    Log.i(TAG, person.toString());
            }
    
            public void testScrollData() throws Exception{
                    OtherPersonService service = new OtherPersonService(this.getContext());
                    List<Person> persons = service.getScrollData(0, 5);
                    for(Person person : persons){
                            Log.i(TAG, person.toString());
                    }
            }
    
            public void testCount() throws Exception{
                    OtherPersonService service = new OtherPersonService(this.getContext());
                    long result = service.getCount();
                    Log.i(TAG, result + "");
            }
    }
    

    原帖地址:http://www.eoeandroid.com/forum.php?mod=viewthread&tid=201307

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  • 原文地址:https://www.cnblogs.com/chenchong/p/2965184.html
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