安卓数据库

1、DBAdapter类： 
package com.cnzcom.android.quickdial;  2   3  import android.content.ContentValues;  4  import android.content.Context;  5 import android.database.Cursor;  6 import android.database.SQLException;  7 import android.database.sqlite.SQLiteDatabase;  8 import android.database.sqlite.SQLiteOpenHelper;  9 import android.util.Log; 10  11 /** 12  *  13  * @author zhangjie 14  * 15  * 数据库相关操作的类 16  */ 17 public class DBAdapter { 18     /** 19      * 数据库名 20      */ 21     private static final String DATABASE_NAME = "quickdial.db"; 22      23     /** 24      * 数据表名 25      */ 26     private static final String DATABASE_TABLE = "quickdial"; 27      28     /** 29      * 数据库版本 30      */ 31     private static final int DATABASE_VERSION = 1; 32      33     /** 34      * key_id ：主键 35      */ 36     @SuppressWarnings("unused") 37     private static final String KEY_ID = "key_id"; 38      39     /** 40      * position ：位置信息，表示数据是第几项 41      */ 42     private static final String POSITION = "position"; 43      44     /** 45      * name ：姓名 46      */ 47     private static final String NAME = "name"; 48      49     /** 50      * phone_number ：电话号码 51      */ 52     private static final String PHONE_NUMBER = "phone_number"; 53      54     /** 55      * ip ：是否ip播出 56      */ 57     private static final String IP = "ip"; 58      59     /** 60      *  61      */ 62     private static final String DATABASE_CREATE = 63         "create table quickdial (key_id INTEGER PRIMARY KEY, " 64             + "position INTEGER, "  65             + "name TEXT, "  66             + "phone_number TEXT, " 67             + "ip INTEGER" 68             + ");"; 69      70     /** 71      *  72      */ 73     private final Context context; 74      75     /** 76      *  77      */ 78     private DatabaseHelper DBHelper; 79      80     /** 81      *  82      */ 83     private SQLiteDatabase db; 84      85     public DBAdapter(Context ctx) { 86         context = ctx; 87         DBHelper = new DatabaseHelper(context); 88          89          90     } 91      92     private static class DatabaseHelper extends SQLiteOpenHelper { 93         public DatabaseHelper(Context context) { 94             super(context, DATABASE_NAME, null, DATABASE_VERSION); 95         } 96  97         @Override 98         public void onCreate(SQLiteDatabase db) { 99             // TODO Auto-generated method stub100             db.execSQL(DATABASE_CREATE);101         }102 103         @Override104         public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {105             // TODO Auto-generated method stub106             db.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE);107             onCreate(db);108         }109         110     }111     112     /**113      * 打开数据库114      * @return115      * @throws SQLException116      */117     public SQLiteDatabase open() throws SQLException118     {119         db = DBHelper.getWritableDatabase();120 121         Cursor cursor = getAll();122         123         if(cursor.getCount() == 0) {124             125             Log.e("数据库为空", "插入数据");126             /**127              * 先使用假数据初始化数据库128              */129             for(int i = 0; i < 10; i++) {130                 insert(i, "", "", 0);131             }  132         } else {133             Log.e("数据库不为空", "读取数据");134         }135         cursor.close();136         137         return db;138     }139     140     /**141      * 关闭数据库142      */143     public void close()144     {145         DBHelper.close();146     }147     148     /**149      * 向数据库中插入数据150      */151 152     public long insert(int position, String name, String phone_number, int ip) {153         154         ContentValues initialValues = new ContentValues();155         initialValues.put(POSITION, position);156         initialValues.put(NAME, name);157         initialValues.put(PHONE_NUMBER, phone_number);158         initialValues.put(IP, ip);159         160         return db.insert(DATABASE_TABLE, null, initialValues);161     }162     163     /**164      * 删除数据,其实不是真正意义上的删除，而是将name = ""、phone_number = ""、ip = 0165      */166     public boolean delete(int position) {167         168         ContentValues initialValues = new ContentValues();169         initialValues.put(POSITION, position);170         initialValues.put(NAME, "");171         initialValues.put(PHONE_NUMBER, "");172         initialValues.put(IP, 0);173         174         return db.update(DATABASE_TABLE, initialValues, POSITION + "=" + position, null) > 0;    175         176 //        return db.delete(DATABASE_TABLE, POSITION + "=" + position, null) > 0;177     }178     179     /**180      * 更改数据181      */182     public boolean update(int position, String name, String phone_number, int ip) {183         184         ContentValues initialValues = new ContentValues();185         //initialValues.put(POSITION, position);186         initialValues.put(NAME, name);187         initialValues.put(PHONE_NUMBER, phone_number);188         initialValues.put(IP, ip);189         190         return db.update(DATABASE_TABLE, initialValues, POSITION + "=" + position, null) > 0;        191     }192     193     public Cursor getAll() {194         195         Cursor cur = db.query(DATABASE_TABLE, 196                 null, null, null, null, null, null);197         return cur;    198         199     }200     201     public Cursor get(long rowId) throws SQLException {202         Cursor cur = db.query(true, DATABASE_TABLE, new String[] {POSITION,203                                                                         NAME,204                                                                         PHONE_NUMBER,205                                                                         IP}, 206                                                                         207                                 POSITION + "=" + rowId, null, null, null, null, null);208         209         if(cur != null) {210             cur.moveToFirst();211         }212         213         return cur;214     }215     216 }
2、Activity中调用：
public DBAdapter m_DBAdapter;2 3 m_DBAdapter = new DBAdapter(this);4 m_DBAdapter.open();