SqliteDatabase 對多個表增刪改查

在創建數據庫時需要創建多張表，並對他們進行增刪改查

一：建立社區裏特幫助類，繼承SQLiteOpenHelper

public class SqlHelper extends SQLiteOpenHelper {
		private static final String DB_NAME = "mydatabase.db";//庫名
		private static final int DB_VERSION = 1;//版本
		private static final String PRIMATY_KEY = " INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT";//主鍵不爲空自動增長

		public SqlHelper(Context context) {
			super(context, DB_NAME, null, DB_VERSION);
		}

		@Override
		public void onCreate(SQLiteDatabase db) {
			/** 創建表 */
			String sql_user = "create table " + UserInfo_tb.TABLE_NAME + "("
					+ UserInfo_tb._ID + " " + PRIMATY_KEY + ","
					+ UserInfo_tb.USER_ID + " varchar(20),"
					+ UserInfo_tb.USER_PSW + " varchar(20),"
					+ UserInfo_tb.USER_REAL_NAME + " varchar(15), )";
			String sql_device = "create table " + Device_tb.TABLE_NAME + "("
					+ Device_tb._ID + " " + PRIMATY_KEY + ","
					+ Device_tb.DEVICE_ID + " varchar(15)," + Device_tb.LAT
					+ " double," + Device_tb.LNG + " double ) ";

			String sql_fence = " create table " + Fence_tb.TABLE_NAME + "("
					+ Fence_tb._ID + " " + PRIMATY_KEY + ","
					+ Fence_tb.DEVICE_ID + " varchar(20) )   ";

			db.execSQL(sql_user);
			db.execSQL(sql_device);
			db.execSQL(sql_fence);

		}

		/* 升級 */
		@Override
		public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

		}
	}

二：自定義內容提供者，繼承ContentProvider

<span style="font-size:18px;">public class DbProvider extends ContentProvider {
	private static final String URI_AUTHORITY = "com.bdyl.user_provider";
	private static final int USER_CODE = 1;
	private static final int DEVICE_CODE = 2;
	private static final int FENCE_CODE = 3;
	private SQLiteDatabase db;
	/** 三張表的Uri */
	public static final Uri URI_USER = Uri.parse("content://" + URI_AUTHORITY
			+ "/" + UserInfo_tb.TABLE_NAME);
	public static final Uri URI_DEVICE = Uri.parse("content://" + URI_AUTHORITY
			+ "/" + Device_tb.TABLE_NAME);
	public static final Uri URI_FENCE = Uri.parse("content://" + URI_AUTHORITY
			+ "/" + Fence_tb.TABLE_NAME);


	private static UriMatcher matcher;// mather類，幫助我們管理識別不同的表
	static {// 向matcher裏添加三張表的uri（authority，表名（path），code根據傳入uri進行匹配，返回的code值來辨識是哪張表）
		matcher = new UriMatcher(UriMatcher.NO_MATCH);
		matcher.addURI(URI_AUTHORITY, UserInfo_tb.TABLE_NAME, USER_CODE);
		matcher.addURI(URI_AUTHORITY, Device_tb.TABLE_NAME, DEVICE_CODE);
		matcher.addURI(URI_AUTHORITY, Fence_tb.TABLE_NAME, FENCE_CODE);
	}


	/** 實例化helper 並得到SQLiteDatabase 實例 */
	@Override
	public boolean onCreate() {
		SqlHelper helper = new SqlHelper(getContext());
		db = helper.getReadableDatabase();
		return false;
	}


	/** 通過matcher類的match方法來匹配對應的表，對其進行更改 */
	@Override
	public Cursor query(Uri uri, String[] projection, String selection,
			String[] selectionArgs, String sortOrder) {
		switch (matcher.match(uri)) {
		case USER_CODE:
			return db.query(BdylDatabase.UserInfo_tb.TABLE_NAME, projection,
					selection, selectionArgs, null, sortOrder, null);
		case DEVICE_CODE:
			return db.query(BdylDatabase.Device_tb.TABLE_NAME, projection,
					selection, selectionArgs, null, sortOrder, null);
		case FENCE_CODE:
			return db.query(Fence_tb.TABLE_NAME, projection, selection,
					selectionArgs, null, sortOrder, null);
		}
		return null;
	}


	@Override
	public String getType(Uri uri) {
		return null;
	}


	@Override
	public Uri insert(Uri uri, ContentValues values) {
		long data = 0;
		switch (matcher.match(uri)) {
		case USER_CODE:
			data = db.insert(UserInfo_tb.TABLE_NAME, null, values);
			break;
		case DEVICE_CODE:
			data = db.insert(Device_tb.TABLE_NAME, null, values);
			break;
		case FENCE_CODE:
			data = db.insert(Fence_tb.TABLE_NAME, null, values);
			break;
		}
		return Uri.withAppendedPath(uri, data + "");
	}


	@Override
	public int delete(Uri uri, String selection, String[] selectionArgs) {
		switch (matcher.match(uri)) {
		case USER_CODE:
			return db.delete(UserInfo_tb.TABLE_NAME, selection, selectionArgs);
		case DEVICE_CODE:
			return db.delete(Device_tb.TABLE_NAME, selection, selectionArgs);
		case FENCE_CODE:
			return db.delete(Fence_tb.TABLE_NAME, selection, selectionArgs);
		}


		return 0;
	}


	@Override
	public int update(Uri uri, ContentValues values, String selection,
			String[] selectionArgs) {
		switch (matcher.match(uri)) {
		case USER_CODE:
			return db.update(BdylDatabase.UserInfo_tb.TABLE_NAME, values,
					selection, selectionArgs);


		case DEVICE_CODE:
			return db.update(Device_tb.TABLE_NAME, values, selection,
					selectionArgs);
		case FENCE_CODE:
			return db.update(Fence_tb.TABLE_NAME, values, selection,
					selectionArgs);
		}
		return 0;
	}
}</span>

<span style="font-size:18px;">三： 你可以用這個provider來寫一個工具類來對相應表進行操作（如下面）</span>

public class ProvideUtils {
	/*
	 * 更新user表，user=?
	 */
	public static void updateUser(ContentResolver resolver,
			ContentValues values, String user) {
		resolver.update(DbProvider.URI_USER, values,
				UserInfo_tb.USER_ID + "=?", new String[] { user });
	}

	/*
	 * 查詢user表 projection信息 user=?
	 */
	public static Cursor queryUser(ContentResolver resolver,
			String[] projection, String user) {
		Cursor cursor = resolver.query(DbProvider.URI_USER, projection,
				UserInfo_tb.USER_ID + "=?", new String[] { user }, null);
		return cursor;
	}

	/** 設備表 device_tb */
	/* user = ? 的所有手錶 */
	public static Cursor queryDeviceList(ContentResolver resolver,
			String[] projection, String userId) {

		return resolver.query(DbProvider.URI_DEVICE, projection,
				Device_tb.USER_ID + "=?", new String[] { userId }, null);
	}

	/* device=？ 的配置信息 */
	public static Cursor queryDeviceInfo(ContentResolver resolver,
			String[] projection, String deviceId) {

		return resolver.query(DbProvider.URI_DEVICE, projection,
				Device_tb.DEVICE_ID + "=?", new String[] { deviceId }, null);
	}}

最後千萬別忘記在Manifist中註冊我們的provider

<provider
            android:name="com.bdyl.database.DbProvider"
            android:authorities="com.bdyl.user_provider" >
        </provider>