Objective-C(onfusion): different simulators show different # of rows/section in table view

Question

I'm working with the Master-Detail template in the blog reader project. I've got several sections in my master table view, each with 1 - 4 rows. Everything shows up as expected in the 4" 64bit iPhone simulator, but when I switch to the 3.5" or 4" simulators, only the first row per section is displayed. Any thoughts as to what might be happening would be appreciated!

EDIT: I was able to get things to work properly for all simulators by changing two lines in this:

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    NSString *sectionYear = [self.years objectAtIndex:section];
    int journalCountForYear = 0;
    for (NSDictionary *dict in self.journalArticles) {
        if ([dict valueForKey:@"year"] == sectionYear) {
            journalCountForYear++;
        }
    }
    return journalCountForYear;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"Cell" forIndexPath:indexPath];

    NSString *sectionYear = [self.years objectAtIndex:indexPath.section];
    NSMutableArray *journalArticlesInSection = [NSMutableArray array];
    for (NSDictionary *dict in self.journalArticles) {
        if ([dict valueForKey:@"year"] == sectionYear) {
            [journalArticlesInSection addObject:dict];
        }
    }

    NSString *title = [journalArticlesInSection[indexPath.row] valueForKey:@"title"];
    NSString *authors = [journalArticlesInSection[indexPath.row] valueForKey:@"authors"];
    cell.textLabel.text = title;
    cell.detailTextLabel.text = authors;
    return cell;
}

I changed both occurrences of this:

[dict valueForKey:@"year"] == sectionYear

to this:

[dict[@"year"] integerValue] == [sectionYear integerValue]

Does anyone know why this would cause problems for the 32bit sims, but not the 64bit one?

Answer 1 · 2014-05-26T00:42:56Z

May 26, 2014 12:42am

When comparing strings DO NOT use == in Objective-C. The == is comparing pointer addresses not the actual value of the strings. Instead use isEqualToString:(NSString).

 NSString *sectionYear = [self.years objectAtIndex:section];
    if ([sectionYear isEqualToString:[dict valueForKey:@"year"]]) {
        journalCountForYear++;
    }

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Michael Covington

Michael Covington

Objective-C(onfusion): different simulators show different # of rows/section in table view

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Darryl Johnson

Darryl Johnson