java.io.FileNotFoundException: No entry for content://media/external/audio/album

[xj179]

被 一个小问题搞了好久，弄得人好郁闷至今还没弄明白原因。代码如下 :

private Bitmap getArtworkFromFile(Context context2, long songID, long albumID) {
		Bitmap bitmap = null;
		if (songID < 0 && albumID < 0) {
			throw new IllegalArgumentException("Must specify an album or a song id");
		}
		BitmapFactory.Options options = new BitmapFactory.Options();
		FileDescriptor fd = null;
		if (albumID < 0) {
			Uri uri = Uri.parse("content://media/external/audio/media/" + songID + "/albumart");
			try {
			ParcelFileDescriptor dfd = context2.getContentResolver().openFileDescriptor(uri, "r");
				if (dfd != null) {
					fd = dfd.getFileDescriptor();
				}
			} catch (FileNotFoundException e) {
				// e.printStackTrace();
			}

		} else {
			Uri uri = ContentUris.withAppendedId(artworkUri, albumID);
			try {
			ParcelFileDescriptor dfd = context2.getContentResolver().openFileDescriptor(uri, "r");
						
				if (dfd != null) {
					fd = dfd.getFileDescriptor();
				}
			} catch (FileNotFoundException e) {
				// e.printStackTrace();
			}
		}
		options.inSampleSize = 1;
		options.inJustDecodeBounds = true;
		BitmapFactory.decodeFileDescriptor(fd, null, options);

		options.inSampleSize = 500;
		options.inJustDecodeBounds = false;
		options.inPreferredConfig = Bitmap.Config.ARGB_8888;
		bitmap = BitmapFactory.decodeFileDescriptor(fd, null, options);
		return bitmap;
	}

运行的时候它会报：java.io.FileNotFoundException: No entry for content://media/external/audio/album异常，异常的代码是在else中的ParcelFileDescriptor dfd = context2.getContentResolver().openFileDescriptor(uri, "r");。奇怪的事来了：我只把代码的结构改成如下 :

private Bitmap getArtworkFromFile(Context context2, long songID, long albumID) {
		Bitmap bitmap = null;
		if (songID < 0 && albumID < 0) {
			throw new IllegalArgumentException(
					"Must specify an album or a song id");
		}
		try {
			BitmapFactory.Options options = new BitmapFactory.Options();
			FileDescriptor fd = null;
			if (albumID < 0) {
				Uri uri = Uri.parse("content://media/external/audio/media/" + songID + "/albumart");
				ParcelFileDescriptor dfd = context2.getContentResolver().openFileDescriptor(uri, "r");
				if (dfd != null) {
					fd = dfd.getFileDescriptor();
				}

			} else {
				Uri uri = ContentUris.withAppendedId(artworkUri, albumID);
				ParcelFileDescriptor dfd = context2.getContentResolver().openFileDescriptor(uri, "r");
				if (dfd != null) {
					fd = dfd.getFileDescriptor();
				}

			}
			options.inSampleSize = 1;
			options.inJustDecodeBounds = true;
			BitmapFactory.decodeFileDescriptor(fd, null, options);

			options.inSampleSize = 500;
			options.inJustDecodeBounds = false;
			options.inPreferredConfig = Bitmap.Config.ARGB_8888;
			bitmap = BitmapFactory.decodeFileDescriptor(fd, null, options);

		} catch (Exception e) {
			 e.printStackTrace() ;
		}
		return bitmap;
	}

它竟然没报错，看了好久也没看出个眉目来，不知道 是什么原因，不知道各位懂不懂，到底是什么原因？