UITableView, Its jerking while scrolling - ios

Question

/Problem is that, I created my own contentviews in UITableview and showing. While scrolling the table view is giving Jerking. How to resolve this issue./
[cell setAccessoryType:UITableViewCellAccessoryDisclosureIndicator];
/ImageDetails, I am receiving from server and loading using lazy loading./
UIImageView *lblImage = [[UIImageView alloc]initWithFrame:CGRectMake(10, 10, 60, 60)];
lblImage.contentMode = UIViewContentModeScaleAspectFill;
[cell.contentView addSubview:lblImage];
if([[[lArray objectAtIndex:indexPath.row] objectForKey:#"Foto"] length] > 0){
NSURL *imageURL = [NSURL URLWithString:[[lMovikidListArray objectAtIndex:indexPath.row] objectForKey:#"MovikitFoto"]];
NSString *key = [[[lArray objectAtIndex:indexPath.row] objectForKey:#"Foto"] MD5Hash];
NSData *data = [FTWCache objectForKey:key];
if (data) {
UIImage *image = [UIImage imageWithData:data];
lblImage.image = image;
} else {
lblImage.image = [UIImage imageNamed:#"defaultprofile.png"];
dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0ul);
dispatch_async(queue, ^{
NSData *data = [NSData dataWithContentsOfURL:imageURL];
[FTWCache setObject:data forKey:key];
UIImage *image = [UIImage imageWithData:data];
dispatch_sync(dispatch_get_main_queue(), ^{
lblImage.image = image;
});
});
}
CALayer *imageLayer = lblImage.layer;
[imageLayer setCornerRadius:lblImage.frame.size.width/2];
[imageLayer setMasksToBounds:YES];
}
else{
lblImage.image = [UIImage imageNamed:#"defaultprofile.png"];
}
UILabel *lblTitle = [[UILabel alloc]initWithFrame:CGRectMake(75, 10, 220, 25)];
lblTitle.text = [NSString stringWithFormat:#"%# - %#", [[lArray objectAtIndex:indexPath.row] objectForKey:#"Name"], [[lArray objectAtIndex:indexPath.row] objectForKey:#"SimNo"]];
lblTitle.font = [UIFont boldSystemFontOfSize:14.0f];
[cell.contentView addSubview:lblTitle];
UILabel *lblSubTitle = [[UILabel alloc]initWithFrame:CGRectMake(100, 40, 195, 35)];
if([[[lArray objectAtIndex:indexPath.row] objectForKey:#"Location"] length] <= 1){
lblSubTitle.text = LOCATION_NOT_AVAILABLE;
lImageName = #"caution_icon.png";
}
else{
lblSubTitle.text = [self calculateDistance:<some data>];
}
lblSubTitle.textColor = [UIColor darkGrayColor];
lblSubTitle.numberOfLines = 2;
lblSubTitle.font = [UIFont italicSystemFontOfSize:12.0f];
[cell.contentView addSubview:lblSubTitle];
/This image is a small image to show some indicators./
UIImageView *lblIndicatorImage = [[UIImageView alloc]initWithFrame:CGRectMake(75, 45, 20, 20)];
lblIndicatorImage.image = [UIImage imageNamed:lImageName];
[cell.contentView addSubview:lblIndicatorImage];
[cell setNeedsDisplay];

Answer 1

You cant do any UIKit operation on background thread. So just remove your graphical operation from background thread and it will be fine.
else {
lblImage.image = [UIImage imageNamed:#"defaultprofile.png"];
dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0ul);
dispatch_async(queue, ^{
NSData *data = [NSData dataWithContentsOfURL:imageURL];
[FTWCache setObject:data forKey:key];
dispatch_async(dispatch_get_main_queue(), ^{
UIImage *image = [UIImage imageWithData:data];
lblImage.image = image;
});
});