Android 多数据库设计实战（ContentProvider）

Android ContentProvider 数据库

更多代码请参考我的个人作品：Stockeye

1. 数据库项目结构

|---ContentProviderTranRec.java
|---SchemaHelperTranDailyRec.java
|---SchemaTranRec.java
|------SchemaTranDailyRec.java
|------SchemaTranMQYRec.java

2. 创建多个数据库

public class ContentProviderTranRec extends ContentProvider {
    // ...
    private static final int TRAN_DAILY_REC_DIR = 1;
    private static final int TRAN_DAILY_REC_ITEM = 2;
    private static final int TRAN_DAILY_REC_ITEM_LIMIT = 3;
    private static final int TRAN_DAILY_REC_ITEM_RANGE = 4;
    private static final int TRAN_MQY_REC_DIR = 11;
    private static final int TRAN_MQY_REC_ITEM = 12;
    private static final int TRAN_MQY_REC_ITEM_LIMIT = 13;
    private static final int TRAN_MQY_REC_ITEM_RANGE = 14;
    static {
        tranRecUriMatcher.addURI(AUTHORITY, "records/daily", TRAN_DAILY_REC_DIR);
        tranRecUriMatcher.addURI(AUTHORITY, "records/daily/#", TRAN_DAILY_REC_ITEM);
        tranRecUriMatcher.addURI(AUTHORITY, "records/daily/limit/#", TRAN_DAILY_REC_ITEM_LIMIT);
        tranRecUriMatcher.addURI(AUTHORITY, "records/daily/range/#", TRAN_DAILY_REC_ITEM_RANGE);
        tranRecUriMatcher.addURI(AUTHORITY, "records/mqy", TRAN_MQY_REC_DIR);
        tranRecUriMatcher.addURI(AUTHORITY, "records/mqy/#", TRAN_MQY_REC_ITEM);
        tranRecUriMatcher.addURI(AUTHORITY, "records/mqy/limit/#", TRAN_MQY_REC_ITEM_LIMIT);
        tranRecUriMatcher.addURI(AUTHORITY, "records/mqy/range/#", TRAN_MQY_REC_ITEM_RANGE);
    }
    private SQLiteDatabase dailyDb = null;
    private SQLiteDatabase mqyDb = null;
    @Override
    public boolean onCreate() {
        dailyDb = new SchemaHelperTranDailyRec().getWritableDatabase();
        mqyDb = new SchemaHelperTranMQYRec().getWritableDatabase();
        return true;
    }
}

public class SchemaHelperTranDailyRec extends SQLiteOpenHelper {
    private String tableName = null;
    private SchemaTranDailyRec schemaTranDailyRec = null;
    private String templateTableName = null;
    protected SchemaHelperTranDailyRec() {
        super(StockeyeApp.appContext, SchemaTranDailyRec.DATABASE_NAME, null, SchemaTranDailyRec.DATABASE_VERSION);
        schemaTranDailyRec = new SchemaTranDailyRec();
        templateTableName = schemaTranDailyRec.getDatabaseTemplateTableName();
    }
    @Override
    public SQLiteDatabase getWritableDatabase() {
        File dbFile = new File( getDatabaseFilePath() + "/" + schemaTranDailyRec.getDatabaseName() );
        if (!dbFile.exists()) {
            try {
                dbFile.createNewFile();
            } catch (IOException ioe) {
                return null;
            }
        }
        return SQLiteDatabase.openOrCreateDatabase(dbFile, null);
    }
    private String getDatabaseFilePath() {
        String dbPath = Environment.getExternalStorageDirectory().getParentFile().getAbsolutePath() + "/sdcard1/stockeye/database";
        File dbDir = new File(dbPath);
        if (!dbDir.exists() && !dbDir.mkdirs()) {
            dbPath = Environment.getExternalStorageDirectory().getAbsolutePath() + "/stockeye/database";
            dbDir = new File(dbPath);
            if (!dbDir.exists() && !dbDir.mkdirs()) {
                return null;
            }
        }
        return dbPath;
    }
}