ObjectAtIndex崩溃

Question

程序崩溃，下面有评论。不确定是什么问题。第一次编程的任何提示？

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

    if(cell == nil){
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:@"MainCell"];
    }

    cell.textLabel.text = [[users objectAtIndex:indexPath.row] objectForKey:[[NSString alloc] initWithFormat:@"%d", indexPath.row]];
    //My program runs but then crashes at this line, I have no idea what's wrong with it though "reason: '-[__NSCFDictionary objectAtIndex:]: unrecognized selector sent to instance"


    return cell;
}

更多代码（不是全部代码）As Requested

- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
    [UIApplication sharedApplication].networkActivityIndicatorVisible = NO;

    users = [NSJSONSerialization JSONObjectWithData:data options:nil error:nil];
    [self.tableView reloadData];
}

- (int)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    return [users count];
}

在.h文件中

  

@interface GIFUsersListViewController：UITableViewController {

NSArray *users;
NSMutableData *data;

     

} @end

Answer 1

截至此消息：'-[__NSCFDictionary objectAtIndex:]: unrecognized selector sent to instance看起来用户不是NSArray，而是NSDictionary。

---

如果您不确定JSON中的内容，请在分配给用户之前进行检查：

id usersFromJSON = [NSJSONSerialization JSONObjectWithData:data options:nil error:nil];
if ([usersFromJSON isKindOfClass:[NSArray class]]) {
    users = usersFromJSON;
} else {
    NSLog(@"Something wrong with my JSON: %@", usersFromJSON);
}