Enable UISearchDisplayController to search text contains string

Question

This is my UISearchDisplayController that works if I perform search and return the result with matching starting alphabet.
However, what I what to do is to enable searching of text contains string.
For example, if I have data chocolate chip and dark chocolate, when I type chocolate on the search bar, I wish to return both result.

The following code only return chocolate chip but not dark chocolate :

self.searchDisplayController = [[[UISearchDisplayController alloc] initWithSearchBar:self.searchBar contentsController:self] autorelease];
self.searchDisplayController.searchResultsDelegate = self;
self.searchDisplayController.searchResultsDataSource = self;
self.searchDisplayController.searchResultsTitle = NSLocalizedString(@"Matches", @"");

- (void)searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText
{
    NSString *text = [searchBar.text stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
    if ([text length]) {
        [self.db fetchCompletionListWithString:text callback:^(NSArray *list) {
            self.prefixArray = list;
            [self.searchDisplayController.searchResultsTableView reloadData];
        }];
    }
}

This is the fetchCompletionListWithString

- (void)_fetchCompletionListWithString:(NSString *)inStr callback:(void(^)(NSArray *))inCallback
{
    if (!inStr || ![inStr length]) {
        return;
    }

    const char *SQL = "SELECT id,title FROM entries WHERE title LIKE ? || '%';";
    ObjSqliteStatement *statement = [[ObjSqliteStatement alloc] initWithSQL:SQL db:db];
    [statement bindText:inStr toColumn:1];
    NSMutableArray *list = [NSMutableArray array];
    while ([statement step]) {
        NSInteger entryID = [statement intFromColumn:0];
        NSString *title = [statement textFromColumn:1];
        if (entryID) {
            [list addObject:@{kMDIdentifierKey:@(entryID), kMDTitleKey:title}];
        }
    }
    [statement release];
    dispatch_async(dispatch_get_main_queue(), ^{
        inCallback(list);
    });
}

I tried to change the *SQL to "SELECT id,title FROM entries WHERE title LIKE ? '%' || '%';". But this do not work.

Any suggestion will be appreciated. Thanks in advance.

Answer 1

Depend on where you query the result.

If you query on an Array, use NSPredicate to filter the result like this.

NSPredicate *predicate = [NSPredicate predicateWithFormat:@"name CONTAINS[cd] %@",searchToken];

If you query on Database, use SQL query like that:

SELECT * FROM mytable
WHERE name LIKE '%chocolate%'

Hope this help.

Base on your edit, you can try this way as a tricky (Because your library you use is so old). If you want to handle SQL, i recommend you use Realm

- (void)_fetchCompletionListWithString:(NSString *)inStr callback:(void(^)(NSArray *))inCallback
{
    if (!inStr || ![inStr length]) {
        return;
    }
inStr = [NSString stringWithFormat:@"%%%@%%",inStr];
    const char *SQL = "SELECT id,title FROM entries WHERE title LIKE ? ;";
    ObjSqliteStatement *statement = [[ObjSqliteStatement alloc] initWithSQL:SQL db:db];
    [statement bindText:inStr toColumn:1];
    NSMutableArray *list = [NSMutableArray array];
    while ([statement step]) {
        NSInteger entryID = [statement intFromColumn:0];
        NSString *title = [statement textFromColumn:1];
        if (entryID) {
            [list addObject:@{kMDIdentifierKey:@(entryID), kMDTitleKey:title}];
        }
    }
    [statement release];
    dispatch_async(dispatch_get_main_queue(), ^{
        inCallback(list);
    });
}