Using SQLite to create a database on android, sqliteandroid

Using SQLite to create a database on android, sqliteandroid
Use SQLite to create a database on android

 

Method:

1. Create a database class that inherits the SQLiteOpenHelper class

Rewrite related functions and initialize database objects.

Public MySQLiteOpenHelper (Context context, int version)

Super (context, "fanfan2.db", null, version );

Helper. getReadableDatabase ();

Override onCreate and onUpgrade

2. Create a database object and obtain the database object

MySQLiteOpenHelper helper = new MySQLiteOpenHelper (getContext (), 1 );

Helper. getReadableDatabase ();

3. To create a new table, type execSQL in oncreate.

In this way, a new student table is created.

    public void onCreate(SQLiteDatabase db) {        Log.d("fanfan", "onCreate");        db.execSQL("CREATE TABLE student(id INTEGER，name TEXT)");    }

4. oncreate is called only when a new database is created. If you have created a database before, it will not be called now.

OnUpgrade is called only after the database version is updated.

 

Code:

Com. fry. MySQLiteOpenHelper

1 package com. fry; 2 3 import android. content. context; 4 import android. database. sqlite. SQLiteDatabase; 5 import android. database. sqlite. SQLiteDatabase. cursorFactory; 6 import android. database. sqlite. SQLiteOpenHelper; 7 import android. util. log; 8 9 public class MySQLiteOpenHelper extends SQLiteOpenHelper {10 11/* 12*1. context 13*2. Database Name 14*3. factory15 * 4. version database file version 16*/17 18 public MySQLiteOpenHelper (Context context, int version) {19 super (context, "fanfan2.db", null, version ); 20 // TODO Auto-generated constructor stub21} 22 23/* call 24 * (non-Javadoc) 25 * @ see android after the database file is created successfully. database. sqlite. SQLiteOpenHelper # onCreate (android. database. sqlite. SQLiteDatabase) 26 */27 @ Override28 public void onCreate (SQLiteDatabase arg0) {29 Log. d ("fanfan", "onCreate"); 30} 31 32/* Call 33 * (non-Javadoc) 34 * @ see android after the database file is updated. database. sqlite. SQLiteOpenHelper # onUpgrade (android. database. sqlite. SQLiteDatabase, int, int) 35 */36 @ Override37 public void onUpgrade (SQLiteDatabase arg0, int arg1, int arg2) {38 Log. d ("fanfan", "onUpgrade"); 39} 40 41}

Database

Com. fanfan. test. Test

 1 package com.fanfan.test; 2  3  4 import com.fry.Activity01; 5 import com.fry.MySQLiteOpenHelper; 6  7 import android.annotation.SuppressLint; 8 import android.test.AndroidTestCase; 9 import android.util.Log;10 11 public class Test extends AndroidTestCase{12     @SuppressLint("NewApi") public void test1(){13         MySQLiteOpenHelper helper=new MySQLiteOpenHelper(getContext(), 1);14         helper.getReadableDatabase();15         String name=helper.getDatabaseName();16         Log.d("test1", name);17     }18     19 20 }

Java Unit Testing

/CreateDatabase2/AndroidManifest. xml

 1 <manifest xmlns:android="http://schemas.android.com/apk/res/android" 2     package="com.example.createDatabase_2" 3     android:versionCode="1" 4     android:versionName="1.0" > 5  6     <uses-sdk 7         android:minSdkVersion="8" 8         android:targetSdkVersion="19" /> 9 10     <application11         android:allowBackup="true"12         android:icon="@drawable/ic_launcher"13         android:label="@string/app_name"14         android:theme="@style/AppTheme" >15         16         <uses-library android:name="android.test.runner"/>17         18         <activity19             android:name="com.fry.MainActivity"20             android:label="@string/app_name" >21             <intent-filter>22                 <action android:name="android.intent.action.MAIN" />23 24                 <category android:name="android.intent.category.LAUNCHER" />25             </intent-filter>26         </activity>27         <activity android:name="com.fry.Activity01" android:exported="true"></activity>28     </application>29     <instrumentation 30         android:name="android.test.InstrumentationTestRunner"31         android:targetPackage="com.example.createDatabase_2" android:label="Test for My app"32         ></instrumentation>33 34 </manifest>

Configuration File