content:// scheme 和 file:// scheme

path 转 Uri (content://)

 /**
     * 根据file path 获取content://
     * @param context
     * @param filePath
     * @return content://
     */
    public static Uri getImageContentUri(Context context, String filePath) {
        Cursor cursor = context.getContentResolver().query(
                MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
                new String[] { MediaStore.Images.Media._ID},
                MediaStore.Images.Media.DATA + "=? ",
                new String[] { filePath }, null);
        if (cursor != null && cursor.moveToFirst()) {
            int id = cursor.getInt(cursor
                    .getColumnIndex(MediaStore.MediaColumns._ID));
            Uri baseUri = Uri.parse("content://media/external/file");
            return Uri.withAppendedPath(baseUri, "" + id);
        } else {
            File file = new File(filePath);
            if (file.exists()) {
                ContentValues values = new ContentValues();
                values.put(MediaStore.Images.Media.DATA, filePath);
                return context.getContentResolver().insert(
                        MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);
            } else {
                return null;
            }
        }
    }