android sd卡数据库读取

先在 Manifest 里添加权限

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

<uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />

然后在 mainActivity 添加方法

	SQLiteDatabase db;
	private final String DATABASE_PATH = android.os.Environment
			.getExternalStorageDirectory().getAbsolutePath() + "/vote";
	private String DATABASE_FILENAME = "db_vote.db";


// 初始化数据库
	private SQLiteDatabase openDatabase() {
		try {
			String databaseFilename = DATABASE_PATH + "/" + DATABASE_FILENAME;
			File dir = new File(DATABASE_PATH);
			if (!dir.exists())
				dir.mkdirs();
			if (!(new File(databaseFilename)).exists()) {
				InputStream is = getResources().openRawResource(R.raw.db_vote);
				FileOutputStream fos = new FileOutputStream(databaseFilename);
				byte[] buffer = new byte[8192];
				int count = 0;
				while ((count = is.read(buffer)) > 0) {
					fos.write(buffer, 0, count);
				}
				fos.close();
				is.close();
			}
			db = SQLiteDatabase.openOrCreateDatabase(databaseFilename, null);
			return db;
		} catch (Exception e) {
			e.printStackTrace();
		}
		return null;
	}