public class MainActivity extends Activity {
     @Override
     public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        //獲取SharedPreferences對象
        Context ctx = MainActivity.this;  
        //第一個參數(shù)指定存儲文件名，第二個參數(shù)指定操作模式
        SharedPreferences sp = ctx.getSharedPreferences("SP", MODE_PRIVATE);
        //存入數(shù)據(jù)
        Editor editor = sp.edit();
        editor.putString("STRING_KEY", "string");
        editor.putInt("INT_KEY", 0);
        editor.putBoolean("BOOLEAN_KEY", true);
        editor.commit();
        //返回STRING_KEY的值 設(shè)定默認(rèn)值
        Log.d("SP", sp.getString("STRING_KEY", "none"));
        //如果NOT_EXIST不存在，則返回值為"none"
        Log.d("SP", sp.getString("NOT_EXIST", "none"));
        //刪除指定數(shù)據(jù)
        editor.remove("STRING_KEY");
        editor.commit();
        //清空數(shù)據(jù)
        editor.clear();
        editor.commit();
     }
}

content://com.example.myapplication.provider/tablename/1

public class MyUsers {
    public static final String AUTHORITY  = “com.wissen.MyContentProvider”;
    // BaseColumn類中已經(jīng)包含了 _id字段
    public static final class User implements BaseColumns {
    public static final Uri CONTENT_URI  = Uri.parse(content://com.example.MyContentProvider”);
     // 表數(shù)據(jù)列
     public static final String  USER_NAME  = “USER_NAME”;
    }
}

package com.wissen.testApp.android;
public class MyContentProvider extends ContentProvider {
    private SQLiteDatabase sqlDB;
    private DatabaseHelper dbHelper;
    private static final String  DATABASE_NAME = “Users.db”;
    private static final int DATABASE_VERSION  = 1;
    private static final String TABLE_NAME   = “User”;
    private static final String TAG = “MyContentProvider”;
    //定義SQLite接口
    private static class DatabaseHelper extends SQLiteOpenHelper {
        DatabaseHelper(Context context) {
            super(context, DATABASE_NAME, null, DATABASE_VERSION);
        }
        @Override
        public void onCreate(SQLiteDatabase db) {
        //創(chuàng)建用于存儲數(shù)據(jù)的表
        db.execSQL(”Create table ” + TABLE_NAME + “( _id INTEGER PRIMARY KEY AUTOINCREMENT, USER_NAME TEXT);”);
        }
        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
            db.execSQL(”DROP TABLE IF EXISTS ” + TABLE_NAME);
            onCreate(db);
        }
    }
    @Override
    public int delete(Uri uri, String s, String[] as) {
        return 0;
    }
    @Override
    public String getType(Uri uri) {
        return null;
    }
    @Override
    public Uri insert(Uri uri, ContentValues contentvalues) {
        sqlDB = dbHelper.getWritableDatabase();
        long rowId = sqlDB.insert(TABLE_NAME, “”, contentvalues);
        if (rowId > 0) {
            Uri rowUri = ContentUris.appendId(MyUsers.User.CONTENT_URI.buildUpon(), rowId).build();
            getContext().getContentResolver().notifyChange(rowUri, null);
            return rowUri;
        }
        throw new SQLException(”Failed to insert row into ” + uri);
    }
    @Override
    public boolean onCreate() {
        dbHelper = new DatabaseHelper(getContext());
        return (dbHelper == null) ? false : true;
    }
    @Override
    public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) {
        SQLiteQueryBuilder qb = new SQLiteQueryBuilder();
        SQLiteDatabase db = dbHelper.getReadableDatabase();
        qb.setTables(TABLE_NAME);
        Cursor c = qb.query(db, projection, selection, null, null, null, sortOrder);
        c.setNotificationUri(getContext().getContentResolver(), uri);
        return c;
    }
    @Override
    public int update(Uri uri, ContentValues contentvalues, String s, String[] as) {
        return 0;
    }
}

public void save() {
        try {
            FileOutputStream outStream=this.openFileOutput("a.txt",Context.MODE_WORLD_READABLE)
            outStream.write(text.getText().toString().getBytes());
            outStream.close();
            //成功消息提示
            Toast.makeText(MyActivity.this,"Saved",Toast.LENGTH_LONG).show();
        } catch (Exception e) {
            e.printStackTrace();
        }
 }

public void load()
{
    try {
        FileInputStream inStream=this.openFileInput("a.txt");
        ByteArrayOutputStream stream=new ByteArrayOutputStream();
        //分塊讀取
        byte[] buffer=new byte[1024];
        int length=-1;
    while((length=inStream.read(buffer))!=-1)   {
            stream.write(buffer,0,length);
        }
        stream.close();
        inStream.close();
        text.setText(stream.toString());
        Toast.makeText(MyActivity.this,"Loaded",Toast.LENGTH_LONG).show();
    } catch (Exception e) {
        e.printStackTrace();
    }
}