Table View changes height when using the search bar

[DevSdk]

Ok, here's how I manage the search bar:

#pragma mark -
#pragma mark Content Filtering

- (void)filterContentForSearchText:(NSString*)searchText
{
	/*
	 Update the filtered array based on the search text and scope.
	 */
	
	[self.filteredArray removeAllObjects]; // First clear the filtered array.
	
	/*
	 Search the main list for products whose type matches the scope (if selected) and whose name matches searchText; add items that match to the filtered array.
	 */
	for (MyObject *object in objectsArray)
	{
		NSRange result = [object.name rangeOfString:searchText options:(NSCaseInsensitiveSearch|NSDiacriticInsensitiveSearch)];
		if (result.location != NSNotFound)
		{
			[self.filteredArray addObject:object];
		}
	}
}

#pragma mark -
#pragma mark UISearchDisplayController Delegate Methods

- (BOOL)searchDisplayController:(UISearchDisplayController *)controller shouldReloadTableForSearchString:(NSString *)searchString
{
    [self filterContentForSearchText:searchString];
    
    // Return YES to cause the search result table view to be reloaded.
    return YES;
}

- (void)searchBarTextDidEndEditing:(UISearchBar *)searchBar
{
	[self.tableView reloadData];
}

Everything works just fine, expect for this problem: the tableview get resized and changes the height when the user inserts something in the search bar; when pressing "search" in the keyboard, the keyboard disappears and the tableview ends at the end of the screen. I would like it to remain in my interface. Anyone has an idea why?