Mutable Array sometimes working for images in UITableView - ios

Question

I am getting a very strange array issue with LogoURL. Sometimes it works and sometimes it errors when trying to display the URL's in the array as an image. This is an Mutable array problem and its driving me crazy.
import "ViewController.h"
#interface ViewController ()
#property (nonatomic, strong) MSTable *table;
#property (nonatomic, strong) NSMutableArray *items;
#property (weak, nonatomic) IBOutlet UITableView *MainTableView;
#end
#implementation ViewController
- (void)viewDidLoad
{
[super viewDidLoad];
// create the activity indicator in the main queue
self.MainTableView.hidden = YES;
UIActivityIndicatorView *ac = [[UIActivityIndicatorView alloc]
initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
[self.view addSubview:ac];
[ac startAnimating];
self.client = [MSClient clientWithApplicationURLString:#"https://mobile.net/" applicationKey:#""];
self.table = [self.client tableWithName:#"notifications"];
self.logoURL = [[NSMutableArray alloc] init];
self.rowitems = [[NSMutableArray alloc] init];
MSQuery *query = [self.table query];
query.fetchLimit = 3;
[query readWithCompletion:^(NSArray *items, NSInteger totalCount, NSError *error)
{
self.rowitems = [items mutableCopy];
//[self.MainTableView reloadData];
int a;
for (a = 0; a < 3; a++)
{
NSDictionary *apt = [self.rowitems objectAtIndex:a];
NSLog(#"%#", apt[#"barID"]);
NSDictionary *barIDDictionary = #{ #"myParam": apt[#"barID"]};
self.client = [MSClient clientWithApplicationURLString:#"https://outnight-mobile.azure-mobile.net/" applicationKey:#"okYeRGfBagYrsbkaqWIRObeDtktjkF10"];
[self.client invokeAPI:#"photos" body:barIDDictionary HTTPMethod:#"POST" parameters:nil headers:nil completion:^(id result, NSHTTPURLResponse *response, NSError *error) {
if (error) {
NSLog(#"Error %#", error );
}
else {
NSString *string = [NSString stringWithFormat:#"%#", [result objectForKey:#"rows"]];
NSString *stringWithoutbracketsend = [string stringByReplacingOccurrencesOfString:#")" withString:#""];
NSString *stringWithoutbracketsfront = [stringWithoutbracketsend stringByReplacingOccurrencesOfString:#"(" withString:#""];
NSString *completion = [stringWithoutbracketsfront stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
NSString *newStr = [completion substringFromIndex:1];
NSString *finalstring = [newStr substringToIndex:newStr.length-(newStr.length>0)];
[self.logoURL insertObject:finalstring atIndex:a];
[self.MainTableView reloadData];
}
}];
}
}];
self.MainTableView.hidden = NO;
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return [self.rowitems count];
}
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
UITableViewCell *cell = [[UITableViewCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:#"cell"];
NSDictionary *stress = [self.rowitems objectAtIndex:indexPath.row];
cell.textLabel.text = stress[#"content"];
if (self.logoURL.count > indexPath.row) {
[cell.imageView setImageWithURL:[NSURL URLWithString:self.logoURL[indexPath.row]] placeholderImage:[UIImage imageNamed:#"greybox40.png"]];
NSLog(#"%#", self.logoURL[indexPath.row]);
}
else
cell.imageView.image = nil;
return cell;
}
#end
I need some fresh eyes on it, can anyone advice ?
thanks

Answer 1

I don’t know much about MSQuery, but if the completion block can be in a separate thread, this is going to mess you up.
The tableView can call -tableView:numberOfRowsInSection: when you have some number of rows, and then call -tableView:cellForRowAtIndexPath: when there’s a totally different number.
Also I don’t know what MSClient is, but if it’s running its completion block in a background thread you’re reloading your tableView in a background thread, so that’s gonna kill you, too.