Android手机开发：SQLite数据库

1. 定义一个类，方便存储和获取数据

package com.eoeAndroid.SQLite;import android.content.ContentValues;import android.content.Context;import android.database.Cursor;import android.database.SQLException;import android.database.sqlite.SQLiteDatabase;import android.database.sqlite.SQLiteOpenHelper;import android.util.Log;public class DataDbAdapter {public static final String KEY_COL = "col";public static final String KEY_TEL = "telephone";private static final String TAG = "DataDbAdapter";private DatabaseHelper mDbHelper;private SQLiteDatabase mDb;private static final String DATABASE_CREATE = "create table tlist (col text primary key, "+ "telephone text not null);";private static final String DATABASE_NAME = "dataBaseMM";private static final String DATABASE_TABLE = "tlist";private static final int DATABASE_VERSION = 1;private final Context mCtx;private static class DatabaseHelper extends SQLiteOpenHelper {DatabaseHelper(Context context) {super(context, DATABASE_NAME, null, DATABASE_VERSION);}@Overridepublic void onCreate(SQLiteDatabase db) {db.execSQL(DATABASE_CREATE);}@Overridepublic void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {db.execSQL("DROP TABLE IF EXISTS list");onCreate(db);}}public DataDbAdapter(Context ctx) {this.mCtx = ctx;}public DataDbAdapter open()  {try {mDbHelper = new DatabaseHelper(mCtx);mDb = mDbHelper.getWritableDatabase();}catch(SQLException e) {Log.i("TTTTT", "尼玛啊，没有建立成功!");}return this;}public void closeclose() {mDbHelper.close();}public long createDiary(String col, String tel) {ContentValues initialValues = new ContentValues();initialValues.put(KEY_COL, col);initialValues.put(KEY_TEL, tel);//String strSql = "insert into " + DATABASE_TABLE + " (" + KEY_COL + ", " + KEY_TEL//+ ") values(col, tel);";//mDb.execSQL(strSql);return mDb.insert(DATABASE_TABLE, null, initialValues);}public boolean deleteDiary(String col) {return mDb.delete(DATABASE_TABLE, KEY_COL + "=" + col, null) > 0;}public Cursor getAllNotes() {return mDb.query(DATABASE_TABLE, new String[] { KEY_COL, KEY_TEL}, null, null, null, null, null);}public Cursor getDiary(String col) throws SQLException {Cursor mCursor =mDb.query(true, DATABASE_TABLE, new String[] { KEY_COL, KEY_TEL}, KEY_COL + "=" + col, null, null,null, null, null);if (mCursor != null) {mCursor.moveToFirst();}return mCursor;}public boolean updateDiary(String col, String tel) {ContentValues args = new ContentValues();args.put(KEY_TEL, tel);return mDb.update(DATABASE_TABLE, args, KEY_COL + "=" + col, null) > 0;}}

2. 使用上面的类，创建对象

private DataDbAdapter mDbHelper;mDbHelper = new DataDbAdapter(this);mDbHelper.open();

open函数创建或打开数据库

3.存储数据

//col和tel是我们要存储的一条记录中的2列数据mDbHelper.createDiary(col, tel);

4. 读取数据，使用Cursor

private Cursor mDataCursor;mDataCursor = mDbHelper.getAllNotes();startManagingCursor(mDataCursor);

private List<Map<String, Object>> items = new ArrayList<Map<String, Object>>();//必须先清除items.clear();Map<String, Object> map = null;for(int i=0; i<mDataCursor.getCount(); i++){mDataCursor.moveToPosition(i);map = new HashMap<String, Object>();map.put("sellitem_1", mDataCursor.getString(0));map.put("sellitem_2", mDataCursor.getString(1));items.add(map);}

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