Home | History | Annotate | Download | only in data 
      1 /*
      2  * Copyright (C) 2013 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package com.android.camera.data;
     18 
     19 import android.content.ContentResolver;
     20 import android.database.Cursor;
     21 import android.net.Uri;
     22 import android.provider.MediaStore;
     23 
     24 import com.android.camera.Storage;
     25 import com.android.camera.debug.Log;
     26 
     27 import java.util.ArrayList;
     28 import java.util.List;
     29 
     30 /**
     31  * A set of queries for loading data from a content resolver.
     32  */
     33 public class FilmstripContentQueries {
     34     private static final Log.Tag TAG = new Log.Tag("LocalDataQuery");
     35     private static final String CAMERA_PATH = Storage.DIRECTORY + "%";
     36     private static final String SELECT_BY_PATH = MediaStore.MediaColumns.DATA + " LIKE ?";
     37 
     38     public interface CursorToFilmstripItemFactory<I extends FilmstripItem> {
     39 
     40         /**
     41          * Convert a cursor at a given location to a Local Data object.
     42          *
     43          * @param cursor the current cursor state.
     44          * @return a LocalData object that represents the current cursor state.
     45          */
     46         public I get(Cursor cursor);
     47     }
     48 
     49     /**
     50      * Query the camera storage directory and convert it to local data
     51      * objects.
     52      *
     53      * @param contentResolver to resolve content with.
     54      * @param contentUri to resolve an item at
     55      * @param projection the columns to extract
     56      * @param minimumId the lower bound of results
     57      * @param orderBy the order by clause
     58      * @param factory an object that can turn a given cursor into a LocalData object.
     59      * @return A list of LocalData objects that satisfy the query.
     60      */
     61     public static <I extends FilmstripItem> List<I> forCameraPath(ContentResolver contentResolver,
     62           Uri contentUri, String[] projection, long minimumId, String orderBy,
     63           CursorToFilmstripItemFactory<I> factory) {
     64         String selection = SELECT_BY_PATH + " AND " + MediaStore.MediaColumns._ID + " > ?";
     65         String[] selectionArgs = new String[] { CAMERA_PATH, Long.toString(minimumId) };
     66 
     67         Cursor cursor = contentResolver.query(contentUri, projection,
     68               selection, selectionArgs, orderBy);
     69         List<I> result = new ArrayList<>();
     70         if (cursor != null) {
     71             while (cursor.moveToNext()) {
     72                 I item = factory.get(cursor);
     73                 if (item != null) {
     74                     result.add(item);
     75                 } else {
     76                     final int dataIndex = cursor.getColumnIndexOrThrow(MediaStore.MediaColumns.DATA);
     77                     Log.e(TAG, "Error loading data:" + cursor.getString(dataIndex));
     78                 }
     79             }
     80 
     81             cursor.close();
     82         }
     83         return result;
     84     }
     85 }