com.xbm.android.matisse.internal.loader.AlbumLoader.java Source code

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Here is the source code for com.xbm.android.matisse.internal.loader.AlbumLoader.java

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/*
 * Copyright (C) 2014 nohana, Inc.
 * Copyright 2017 Zhihu Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.xbm.android.matisse.internal.loader;

import android.content.Context;
import android.database.Cursor;
import android.database.MatrixCursor;
import android.database.MergeCursor;
import android.net.Uri;
import android.provider.MediaStore;
import android.support.v4.content.CursorLoader;
import com.xbm.android.matisse.internal.entity.Album;
import com.xbm.android.matisse.internal.entity.SelectionSpec;

/**
 * Load all albums (grouped by bucket_id) into a single cursor.
 */
public class AlbumLoader extends CursorLoader {
    public static final String COLUMN_COUNT = "count";
    private static final Uri QUERY_URI = MediaStore.Files.getContentUri("external");
    private static final String[] COLUMNS = { MediaStore.Files.FileColumns._ID, "bucket_id", "bucket_display_name",
            MediaStore.MediaColumns.DATA, COLUMN_COUNT };
    private static final String[] PROJECTION = { MediaStore.Files.FileColumns._ID, "bucket_id",
            "bucket_display_name", MediaStore.MediaColumns.DATA, "COUNT(*) AS " + COLUMN_COUNT };

    // === params for showSingleMediaType: false ===
    private static final String SELECTION = "(" + MediaStore.Files.FileColumns.MEDIA_TYPE + "=?" + " OR "
            + MediaStore.Files.FileColumns.MEDIA_TYPE + "=?)" + " AND " + MediaStore.MediaColumns.SIZE + ">0"
            + ") GROUP BY (bucket_id";
    private static final String[] SELECTION_ARGS = { String.valueOf(MediaStore.Files.FileColumns.MEDIA_TYPE_IMAGE),
            String.valueOf(MediaStore.Files.FileColumns.MEDIA_TYPE_VIDEO), };
    // =============================================

    // === params for showSingleMediaType: true ===
    private static final String SELECTION_FOR_SINGLE_MEDIA_TYPE = MediaStore.Files.FileColumns.MEDIA_TYPE + "=?"
            + " AND " + MediaStore.MediaColumns.SIZE + ">0" + ") GROUP BY (bucket_id";

    private static String[] getSelectionArgsForSingleMediaType(int mediaType) {
        return new String[] { String.valueOf(mediaType) };
    }
    // =============================================

    private static final String BUCKET_ORDER_BY = "datetaken DESC";

    private AlbumLoader(Context context, String selection, String[] selectionArgs) {
        super(context, QUERY_URI, PROJECTION, selection, selectionArgs, BUCKET_ORDER_BY);
    }

    public static CursorLoader newInstance(Context context) {
        String selection;
        String[] selectionArgs;
        if (SelectionSpec.getInstance().onlyShowImages()) {
            selection = SELECTION_FOR_SINGLE_MEDIA_TYPE;
            selectionArgs = getSelectionArgsForSingleMediaType(MediaStore.Files.FileColumns.MEDIA_TYPE_IMAGE);
        } else if (SelectionSpec.getInstance().onlyShowVideos()) {
            selection = SELECTION_FOR_SINGLE_MEDIA_TYPE;
            selectionArgs = getSelectionArgsForSingleMediaType(MediaStore.Files.FileColumns.MEDIA_TYPE_VIDEO);
        } else {
            selection = SELECTION;
            selectionArgs = SELECTION_ARGS;
        }
        return new AlbumLoader(context, selection, selectionArgs);
    }

    @Override
    public Cursor loadInBackground() {
        Cursor albums = super.loadInBackground();
        MatrixCursor allAlbum = new MatrixCursor(COLUMNS);
        int totalCount = 0;
        String allAlbumCoverPath = "";
        if (albums != null) {
            while (albums.moveToNext()) {
                totalCount += albums.getInt(albums.getColumnIndex(COLUMN_COUNT));
            }
            if (albums.moveToFirst()) {
                allAlbumCoverPath = albums.getString(albums.getColumnIndex(MediaStore.MediaColumns.DATA));
            }
        }
        allAlbum.addRow(new String[] { Album.ALBUM_ID_ALL, Album.ALBUM_ID_ALL, Album.ALBUM_NAME_ALL,
                allAlbumCoverPath, String.valueOf(totalCount) });

        return new MergeCursor(new Cursor[] { allAlbum, albums });
    }

    @Override
    public void onContentChanged() {
        // FIXME a dirty way to fix loading multiple times
    }
}