Android数据存储和数据访问要点

1、南昌航空大学实验报告二0一 4 年 11月14 日课程名称：Android 实验名称： Android 数据存储和数据访问 班级：姓名：_同组人：指导教师评定：签名：一：实验目的掌握SharedPreferences的使用方法；掌握各种文件存储的区别与适用情况；了解SQLite数据库的特点和体系结构；掌握SQLite数据库的建立和操作方法；理解ContentProvider的用途和原理；掌握ContentProvider的创建与使用方法二：实验工具Eclipse ( MyEclipse ) + ADT + Android2.2 SDK ;三：实验题目1 .应用程序一般允许用户自己定义配置信息，

2、如界面背景颜色、字体大小和字体颜色等，尝试使用SharedPreferences保存用户的自定义配置信息，并在程序启动时自动加载这些自定义的配置信息。2 .尝试把第1题的用户自己定义配置信息，以 INI文件的形式保存在内部存储器上。3 .使用代码建库的方式，创建名为test.db的数据库，并建立 staff数据表，表内的属性值如下表所示：属性数据类型说明_idinteger主键nametext姓名sextext性别departmenttext所在部门salaryfloat工资实验目的掌握 SharedPreferences 的使用方法；掌握各种文件存储的区别与适 用情况；了解SQLite数据库

3、的特点和 体系结构；掌握SQLite数据库的建立和 操作方法；理解ContentProvider的用途和 原理；掌握ContentProvider的创建与 使用方法实验工具Eclipse (MyEclipse ) + ADT + Android2.2 SDK ;实验题目1 .应用程序一般允许用户自己 定义配置信息，如界面背景颜色、 字体大小和字体颜色等，尝试使用 SharedPreferences保存用户的自定 义配置信息，并在程序启动时自动 加载这些自定义的配置信息。2 .尝试把第1题的用户自己定 义配置信息，以INI文件的形式保 存在内部存储器上。3 .使用代码建库的方式，创建 名为tes

4、t.db的数据库，并建立staff 数据表，表内的属性值如下表所示：数据类型说明主键integernametext姓名sextext性别departmenttext所在部门salaryfloat工资4.建 立 一 个ContentProvider ,用来共学第 3题所建立的数据库；4.建立一个ContentProvider ,用来共享第3题所建立的数据库;四：实验代码Internalpublic classInternalextends Activity privatefinal String =""privateTextViewlabelView ;privateText

5、ViewdisplayView ;privateCheckBoxappendBox ;privateOverrideEditTextentryText ;public 、void onCreate(Bundle savedInstanceState) super .onCreate(savedlnstanceState);setContentView(R.layout.main );display );append );entry );labelView = (TextView)findViewById(R.id.label );displayView = (TextView)findView

6、ById(R.id.appendBox= (CheckBox)findViewById(R.id.entryText= (EditText)findViewById(R.id.write );read );writeButtonListener);readButtonListener );Button writeButton = (Button)findViewById(R.id. Button readButton = (Button)findViewById(R.id. writeButton.setOnClickListener( readButton.setOnClickListene

7、r(entryText.selectAll();entryText.findFocus();OnClickListenerwriteButtonListenernew OnClickListener() public void onClick(View v) Overridefos =try nullif ( appendBox .isChecked()fos = open(,Context.MODE_APPEND);else fos = open(,Context.MODE_PRIVATE );String text =entryText .getText().toString();fos.

8、write(text.getBytes();labelView.setText(" 文件写入成功，写入长度：" +text.length();entryText.setText("" ); catch ( e) e.printStackTrace();catch (IOException e) e.printStackTrace();finally if (fos != null ) try fos.flush();fos.close(); catch (IOException e) e.printStackTrace();= new OnClickLi

9、stener() OnClickListenerreadButtonListenerOverridepublic void onClick(View v) displayView .setText( "" );fis = null try fis = open();if (fis.available() = 0) return ;byte readBytes = new byte fis.available();while (fis.read(readBytes) != -1)new String(readBytes);String text = displayView .

10、setText(text); labelView .setText( "文件读取成功，文件长度："+text.length(); catch ( e) e.printStackTrace();catch (IOException e) e.printStackTrace();SimplePreferenceDemopublic class SimplePreferenceDemoextends Activity privateEditTextnameText ;privateEditTextageText ;privateEditTextheightText ;public

11、staticfinal StringPREFERENCE_NAME = "SaveSetting"publicstaticintMODE = Context.MODE WORLDREADABLE +Context.MODE WORLD WRITEABLE;Overridepublic void onCreate(Bundle savedInstanceState) super .onCreate(savedInstanceState);setContentView(R.layout.main );nameText = (EditText)findViewById(R.id.

12、name);ageText = (EditText)findViewById(R.id.age );heightText = (EditText)findViewById(R.id.height );Overridepublic void onStart()super .onStart();l oadSharedPreferences();Overridepublic void onStop()super .onStop(); saveSharedPreferences();private void loadSharedPreferences()SharedPreferences shared

13、Preferences = getSharedPreferences( PREFERENCE_NAME, MODE);String name = sharedPreferences.getString("Name" , "Tom");int age = sharedPreferences.getInt("Age" , 20);float height = sharedPreferences.getFloat("Height" ,1.81f);nameText .setText(name);ageText .setT

14、ext(String.valueOf (age);heightText .setText(String.valueOf (height);private void saveSharedPreferences()SharedPreferences sharedPreferences = getSharedPreferences( PREFERENCE_NAME, MODE);SharedPreferences.Editor editor = sharedPreferences.edit();editor.putString("Name" , nameText .getText

15、().toString();editor.putInt("Age",Integer. parseInt (ageText .getText().toString(); editor.putFloat("Height" ,Float. parseFloat (heightText .getText().toString(); mit();SQLiteDemoDBAdapter.java public class DBAdapter privatestaticfinalStringDB_NAME ="people.db"privatest

16、aticfinalStringDB_TABLE ="peopleinfo"privatestaticfinalintDB_VERSION = 11;publicstaticfinalStringKEY_ID = "_id"publicstaticfinalStringKEY_NAME ="name"public publicstaticfinalstaticfinalStringKEY_AGE =StringKEY_HEIGHT"age" ;= "height"privateSQLiteData

17、basedb ;privatefinal Contextcontext ;privateDBOpenHelperdbOpenHelper ;publicDBAdapter(Context_context) context = _context;/* Close the database */ public void close() if ( db != null ) db .close();db = null ;/* Open the database */nullpublic void open() throws SQLiteException dbOpenHelper = new DBOp

18、enHelper( context , DB_NAME, DB_VERSION );try db = dbOpenHelper .getWritableDatabase();catch (SQLiteException ex) db = dbOpenHelper .getReadableDatabase(); public long insert(People people) ContentValues newValues =new ContentValues();newValues.put( KEY_NAME, people. Name);newValues.put( KEY_AGE , p

19、eople. Age );newValues.put( KEY_HEIGHT , people. Height );return db .insert( DB_TABLE , null , newValues); public People queryAllData() Cursor results =db .query( DB_TABLE , new String KEY_IDKEY_NAME, KEY_AGE, KEY_HEIGHT ,null , null , null , null , null );return ConvertToPeople(results);public Peop

20、le queryOneData(long id) Cursor results =db .query(KEY_NAME, KEY_AGE, KEY_HEIGHT , KEY_ID + "=" + id,DB_TABLE , new String null , null , null , null );KEY_IDreturn ConvertToPeople(results); private People ConvertToPeople(Cursor cursor) int resultCounts = cursor.getCount();if (resultCounts

21、= 0 | !cursor.moveToFirst() return null ;People peoples =new PeopleresultCounts;for ( int i = 0 ; i<resultCounts; i+)peoplesi =new People();peoplesi. ID = cursor.getInt(0);peoplesi. Name = cursor.getString(cursor.getColumnIndex( peoplesi.Age =cursor.getInt(cursor.getColumnIndex(peoplesi.Height=cu

22、rsor.getFloat(cursor.getColumnIndex(KEY_NAME);KEY_AGE );KEY_HEIGHT );cursor.moveToNext();return peoples;publiclong deleteAllData() return db .delete( DB_TABLE , null , null ); public long deleteOneData( long id) return db .delete( DB_TABLE , KEY_ID + "=" + id,null );public long updateOneDa

23、ta(long id , People people)ContentValues updateValues =new ContentValues();updateValues.put(updateValues.put(updateValues.put(KEY_NAME, people.KEY_AGE, people.KEY_HEIGHT , people.Name);Age)；Height )；return db.update(DB_TABLE , updateValues,KEY_ID + "=" + id,null ); /* 静态Helper类，用于建立、更新和打开数

24、据库private static class DBOpenHelper extends*/SQLiteOpenHelper public DBOpenHelper(Contextcontext, String name, CursorFactoryfactory,int version) super (context, name, factory, version); private static final StringDBCREATE = "create table "DB_TABLE + " (" + KEY_ID +"integer p

25、rimary key autoincrement,KEY_NAME+ " text not null,"+ KEY_AGE+ " integer,"+ KEYHEIGHTOverride public void _db.execSQL(+ " float);"onCreate(SQLiteDatabase _db) DB_CREATE);Override public void_newVersion) _db.execSQL( onCreate(_db);onUpgrade(SQLiteDatabase"DROP TABLE

26、 IF EXISTS "_db, int _oldVersion,+ DB_TABLE );intPeople.javapublic class People publicint ID = -1;publicpublicString Name;int Age;public floatHeightOverridepublic String toString()String result =""result +="ID : " + thisresult +="姓名："+thisresult +="年龄："+t

27、hisresult +="身高："+thisreturn result;ID + ",".Name + ",".Age + ",".Height + ","61SQLiteDemo.javapublic class SQLiteDemo extends Activity /* Called when the activity is first created. */ private DBAdapter dbAdepter ;private EditTextnameText ;privateEdi

28、tTextageText ;privateEditTextheightTextprivateEditTextidEntry ;privateTextViewlabelView;privateTextViewdisplayView;Overridepublic void onCreate(Bundle savedInstanceState) super .onCreate(savedInstanceState);setContentView(R.layout.main );nameText=(EditText)findViewById(R.);ageText =(EditText)

29、findViewById(R.id.age );heightText=(EditText)findViewById(R.id.heightidEntry =(EditText)findViewById(R.id.id_entry )labelView=(TextView)findViewById(R.id.label );displayView=(TextView)findViewById(R.id.display);add );query_all );clear );delete_all );query );delete );update );Button addButton = (Butt

30、on)findViewById(R.id.Button queryAllButton = (Button)findViewById(R.id.Button clearButton = (Button)findViewById(R.id.Button deleteAllButton = (Button)findViewById(R.id.Button queryButton = (Button)findViewById(R.id.Button deleteButton = (Button)findViewById(R.id.Button updateButton = (Button)findVi

31、ewById(R.id.addButton.setOnClickListener( queryAllButton.setOnClickListener( clearButton.setOnClickListener( deleteAllButton.setOnClickListener(queryButton.setOnClickListener( deleteButton.setOnClickListener( updateButton.setOnClickListener(dbAdepter = new DBAdapter( dbAdepter .open();OnClickListene

32、raddButtonListeneraddButtonListener );queryAllButtonListener);clearButtonListener);deleteAllButtonListener);queryButtonListener);deleteButtonListener);updateButtonListener);this );= new OnClickListener() Overridepublic void onClick(View v) People people = new People();people. Name = nameText .getTex

33、t().toString();people. Age =Integer.parseInt ( ageText .getText().toString();people. Height =Float. parseFloat( heightText .getText().toString();long colunm = dbAdepter .insert(people);if (colunm = -1 )labelView.setText(" 添加过程错误！" ); else labelView.setText(" 成功添加数据，ID ：+String. valueO

34、f (colunm);OnClickListenerqueryAllButtonListener= new OnClickListener() Override public void onClick(View v) People peoples =dbAdepter .queryAllData();if (peoples = null )labelView .setText( " 数据库中没有数据" );return ;labelView .setText( " 数据库：" );String msg ="" ;for ( int i

35、 = 0 ; i<peoples.length ; i+)msg += peoplesi.toString()+"n" ; displayView .setText(msg); ;OnClickListenerclearButtonListener= new OnClickListener() Overridepublic void onClick(View v) displayView .setText( "" );= new OnClickListener() OnClickListenerdeleteAllButtonListenerOverridepublic void onClick(View v) dbAdepter .deleteAllData();String msg =" 数据全部删除labelView .setText(msg);OnClickListenerqueryButtonListener= new OnClickListener() Override public void onClick(View v) int id = I