Android SQLite Data Operations

Main. xml file:

01 <? Xml version = "1.0" encoding = "UTF-8"?>

02 <LinearLayout xmlns: android = "http://schemas.android.com/apk/res/android"

03 android: orientation = "vertical"

04 android: layout_width = "fill_parent"

05 android: layout_height = "fill_parent"

06>

07 <Button

08 android: layout_width = "fill_parent"

09 android: layout_height = "wrap_content"

10 android: id = "@ + id/create"

11 android: text = "creating a database"

12/>

13 <Button

14 android: layout_width = "fill_parent"

15 android: layout_height = "wrap_content"

16 android: id = "@ + id/upgrade"

17 android: text = "Update Database"

18/>

19 <Button

20 android: layout_width = "fill_parent"

21 android: layout_height = "wrap_content"

22 android: id = "@ + id/insert"

23 android: text = "inserting data"

24/>

25 <Button

26 android: layout_width = "fill_parent"

27 android: layout_height = "wrap_content"

28 android: id = "@ + id/update"

29 android: text = "modify data"

30/>

31 <Button

32 android: layout_width = "fill_parent"

33 android: layout_height = "wrap_content"

34 android: id = "@ + id/select"

35 android: text = "querying data"

36/>

37 </LinearLayout>

The MyOpenHleper class inherited from SQLiteOpenHelper:
01 package com. android. danny. hleper;

02

03 import android. content. Context;

04 import android. database. sqlite. SQLiteDatabase;

05 import android. database. sqlite. SQLiteOpenHelper;

06

07 public class MyOpenHleper extends SQLiteOpenHelper {

08

09 public static final int VERSION = 1;

10

11 public MyOpenHleper (Context context, String name ){

12 super (context, name, null, VERSION );

13 // TODO Auto-generated constructor stub

14}

15

16 public MyOpenHleper (Context context, String name, int ver ){

17 super (context, name, null, ver );

18 // TODO Auto-generated constructor stub

19}

20 @ Override

21 public void onCreate (SQLiteDatabase db ){

22 System. out. println ("------ Create Database ----");

23 db.exe cSQL ("create table person (id int, name varchar (20 ))");

24}

25

26 @ Override

27 public void onUpgrade (SQLiteDatabase arg0, int arg1, int arg2 ){

28 // TODO Auto-generated method stub

29 System. out. println ("------ Upgrade Database ----");

30}

31

32}

SQLite data operation class:

01 package com. android. danny. db;

02

03 import com. android. danny. hleper. MyOpenHleper;

04

05 import android. app. Activity;

06 import android. content. ContentValues;

07 import android. database. Cursor;

08 import android. database. sqlite. SQLiteDatabase;

09 import android. OS. Bundle;

10 import android. view. View;

11 import android. view. View. OnClickListener;

12 import android. widget. Button;

13

14 public class Sqlite3 extends Activity implements OnClickListener {

15

16 Button create;

17 Button upgrade;

18 Button insert;

19 Button update;

20 Button select;

21

22 @ Override

23 public void onCreate (Bundle savedInstanceState ){

24 super. onCreate (savedInstanceState );

25 setContentView (R. layout. main );

26

27 create = (Button) findViewById (R. id. create );

28 upgrade = (Button) findViewById (R. id. upgrade );

29 insert = (Button) findViewById (R. id. insert );

30 update = (Button) findViewById (R. id. update );

31 select = (Button) findViewById (R. id. select );

32

33 create. setOnClickListener (this );

34 upgrade. setOnClickListener (this );

35 insert. setOnClickListener (this );

36 update. setOnClickListener (this );

37 select. setOnClickListener (this );

38}

39

40 @ Override

41 public void onClick (View v ){

42 MyOpenHleper dbDatabase;

43 if (v = create ){

44 dbDatabase = new MyOpenHleper (this, "test_db.db ");

45 // create a database

46 dbDatabase. getWritableDatabase ();

47

48} else if (v = upgrade ){

49 // update the database

50 dbDatabase = new MyOpenHleper (this, "test_db.db", 2 );

51 dbDatabase. getReadableDatabase ();

52

53} else if (v = insert ){

54 // insert data

55 ContentValues values = new ContentValues ();

56 values. put ("id", 1 );

57 values. put ("name", "danny ");

58 dbDatabase = new MyOpenHleper (this, "test_db.db ");

59 SQLiteDatabase database = dbDatabase. getWritableDatabase ();

60 database. insert ("person", null, values );

61

62} else if (v = update ){

63 // modify data

64 ContentValues values = new ContentValues ();

65 values. put ("name", "danny & kiki ");

66 dbDatabase = new MyOpenHleper (this, "test_db.db ");

67 SQLiteDatabase database = dbDatabase. getWritableDatabase ();

68 database. update ("person", values, "id =? ", New String [] {" 1 "});

69

70} else if (v = select ){

71 // data query operation

72 dbDatabase = new MyOpenHleper (this, "test_db.db ");

73 SQLiteDatabase database = dbDatabase. getReadableDatabase ();

74 Cursor cursor = database. query ("person", new String [] {"id", "name "},

75 "id =? ", New String [] {" 1 "},

76 null, null, null );

77 while (cursor. moveToNext ()){

78 String name = cursor. getString (cursor. getColumnIndex ("name "));

79 System. out. println ("query: ----->" + name );

80}

81}

82

83}

84}