Show UIAlertView if UITableView is empty

I have RSS, and the UITableView loads data from it, how can I show UIAlertView if the UITableView is empty, but not by count of an array because the array is different every time it is refreshed, is there some kind of function which w开发者_如何学运维ill check if UITableView is empty after it completes drawing?

You can query the UITableView itself. So assuming you have a single section you could do the following ...

// Reload the tableview
[tableView reloadData];
// Test the number of rows in the first section
if ([tableView numberofRowsInSection:0] == 0) {
    // Display UIAlertView here
}

EDIT; Based on the comments below ...

In your header file (.h) iVar declarations ...

int feedCount;
int feedsParsed;

In your implementation ...

- (void)refresh {
    feedCount = 0;
    feedsParsed = 0;

    [feedParser stopParsing];
    self.title = @"Refreshing...";
    [parsedItems removeAllObjects];
    for (NSString *imePredmeta in [Data variables].mojiPredmeti) {
        ... // I've removed these lines for brevity but they are still required
        [feedParser parse];
        feedCount += 1;
    }
    // Delete everything else after this line
}

- (void)feedParserDidFinish:(MWFeedParser *)parser {
    feedsParsed += 1;
    if (feedsParsed == feedCount) {
        [self.tableView reloadData];
        if ([self.tableView numberofRowsInSection:0] == 0) {
            // Fade out tableview and display alert here as we now know for
            // sure that there are no more feeds to parse and we definitely
            // have nothing to display
        }
    }
 } 

You will need to loop round the array and check to determine if there are no results. Please post your existing tableview code if you want a more explicit answer.

edit: micpringle answer above is better.