@Override
public int delete(Uri uri, String selection, String[] selectionArgs) {
final SQLiteDatabase db = flickrDbHelper.getWritableDatabase();
final int match = uriMatcher.match(uri);
int rowsDeleted;
// this makes delete all rows return the number of rows deleted
if (selection == null) {
selection = "1";
}
switch (match) {
case PICTURE:
rowsDeleted = db.delete(FlickrContract.PictureEntry.TABLE_NAME, selection, selectionArgs);
break;
default:
throw new UnsupportedOperationException("Unknown uri: " + uri);
}
// Because a null deletes all rows
if (rowsDeleted != 0) {
getContext().getContentResolver().notifyChange(uri, null);
}
return rowsDeleted;
}
@Nullable
@Override
public Cursor query(
Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) {
Cursor cursor;
// Here's the switch statement that, given a URI, will determine what kind of request it is,
// and query the database accordingly.
final int match = uriMatcher.match(uri);
if (match == PICTURE) {
cursor =
flickrDbHelper
.getReadableDatabase()
.query(
FlickrContract.PictureEntry.TABLE_NAME,
projection,
selection,
selectionArgs,
null,
null,
sortOrder);
} else if (match == PICTURE_WITH_ID) {
cursor =
flickrDbHelper
.getReadableDatabase()
.query(
FlickrContract.PictureEntry.TABLE_NAME,
projection,
selection,
selectionArgs,
null,
null,
sortOrder);
} else {
throw new UnsupportedOperationException("Unknown uri: " + uri);
}
/**
* set notificationUri for the cursor to the one that was passed into the function The cursor
* registers the content observer to watch for changes to that uri and any of its descendants to
* notify changes on update or insert.
*/
cursor.setNotificationUri(getContext().getContentResolver(), uri);
return cursor;
}
@Override
public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) {
final SQLiteDatabase db = flickrDbHelper.getWritableDatabase();
final int match = uriMatcher.match(uri);
int rowsUpdated;
switch (match) {
case PICTURE:
rowsUpdated =
db.update(FlickrContract.PictureEntry.TABLE_NAME, values, selection, selectionArgs);
break;
default:
throw new UnsupportedOperationException("Unknown uri: " + uri);
}
if (rowsUpdated != 0) {
getContext().getContentResolver().notifyChange(uri, null);
}
return rowsUpdated;
}
@Nullable
@Override
public Uri insert(Uri uri, ContentValues values) {
final SQLiteDatabase db = flickrDbHelper.getWritableDatabase();
final int match = uriMatcher.match(uri);
Uri returnUri;
switch (match) {
case PICTURE:
// insert returns the row id of the inserted row, -1 if there's an error
long _id = db.insert(FlickrContract.PictureEntry.TABLE_NAME, null, values);
if (_id > 0) {
returnUri = FlickrContract.PictureEntry.buildPictureUri(_id);
} else {
throw new android.database.SQLException("Failed to insert row into " + uri);
}
break;
default:
throw new UnsupportedOperationException("Unknown uri: " + uri);
}
getContext().getContentResolver().notifyChange(uri, null);
return returnUri;
}