DataProvider.java 文件源码

@Override
public int delete(@NonNull Uri uri, String selection, String[] selectionArgs) {

    final SQLiteDatabase db_g = mOpenHelper_gallery.getReadableDatabase();
    final SQLiteDatabase db_a = mOpenHelper_article.getReadableDatabase();
    final int match = sUriMatcher.match(uri);
    int rowDeleted;

    if (selection == null) selection = "1";

    switch (match) {
        case IMAGE:
            rowDeleted = db_g.delete(TABLE_NAME_GALLERY, selection, selectionArgs);
            break;

        case ARTICLE:
            rowDeleted = db_a.delete(TABLE_NAME_ARTICLE, selection, selectionArgs);
            break;

        default:
            throw new UnsupportedOperationException("Unknown uri: " + uri);
    }

    if (rowDeleted != 0) {
        getContext().getContentResolver().notifyChange(uri, null);
    }

    return rowDeleted;
}