ios tableview image load duplicate when scrolling tableview - ios

Question

I make two custom cell and display in single UITableView in odd even orders, but when i scroll UITableView all image and schedule data color will change randomly and duplicate data will displayed but name,exp., pri-zone, and rate which is in string they all display proper,only image and color of schedule text will change.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath: (NSIndexPath *)indexPath
{
if (indexPath.row % 2 == 0) {
static NSString *cellIdentifier=#"MyCustomCell";
TableViewCell *cell=[tblResponseData dequeueReusableCellWithIdentifier:cellIdentifier];
if (cell == nil)
{
cell = [[TableViewCell alloc] initWithStyle:UITableViewCellStyleValue1
reuseIdentifier:cellIdentifier];
}
NSString *imgPath=[[arrData objectAtIndex:indexPath.row]valueForKey:#"Pic"];
// NSString *imgPath=[[appDelegate.arrData
objectAtIndex:indexPath.row]valueForKey:#"image"];
NSURL *url = [NSURL URLWithString:[imgPath
stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];
NSString *schedule =[[arrData objectAtIndex:indexPath.row]valueForKey:#"Schedule"];
NSArray *strings = [schedule componentsSeparatedByString:#","];
//NSURL *url = [NSURL URLWithString:url];
[NSURLConnection sendAsynchronousRequest:[NSURLRequest requestWithURL:url]
queue:[NSOperationQueue currentQueue]
completionHandler:^(NSURLResponse * resp, NSData * data, NSError
* error)
{
if(error == NULL){
// here is our image
UIImage *image = [UIImage imageWithData:data];
cell.imgThumbnail.image=image;
}
else{
cell.imgThumbnail.image=[UIImage imageNamed:#"no preview 2.jpeg"];
}
}];
for (NSString *item in strings)
{
if ([item isEqualToString:#"Su"]) {
cell.lblsu.textColor = [UIColor greenColor];
}else if ([item isEqualToString:#"Tu"]){
cell.lblt.textColor = [UIColor greenColor];
}else if ([item isEqualToString:#"Th"]){
cell.lblth.textColor = [UIColor greenColor];
}
else if ([item isEqualToString:#"M"]){
cell.lblm.textColor = [UIColor greenColor];
}
else if ([item isEqualToString:#"F"]){
cell.lblf.textColor = [UIColor greenColor];
}
else if ([item isEqualToString:#"S"]){
cell.lbls.textColor = [UIColor greenColor];
}
else if ([item isEqualToString:#"W"]){
cell.lblw.textColor = [UIColor greenColor];
}
}
cell.lblname.text = [[arrData objectAtIndex:indexPath.row] valueForKey:#"Worker Name"];
cell.lblexperience.text=[[arrData o
bjectAtIndex:indexPath.row]valueForKey:#"Experience"];
cell.lblprizone.text=[[arrData objectAtIndex:indexPath.row]valueForKey:#"Primary
Zone"];
cell.lblrate.text=[[arrData objectAtIndex:indexPath.row]valueForKey:#"Rate"];
return cell;
} else {
static NSString *cellIdentifier1=#"MyCustomCell1";
TableViewCell *cell1=[tblResponseData d
equeueReusableCellWithIdentifier:cellIdentifier1];
if (cell1 == nil)
{
cell1 = [[TableViewCell alloc] initWithStyle:UITableViewCellStyleValue1
reuseIdentifier:cellIdentifier1];
}
NSString *imgPath=[[arrData objectAtIndex:indexPath.row]valueForKey:#"Pic"];
// NSString *imgPath=[[appDelegate.arrData
objectAtIndex:indexPath.row]valueForKey:#"image"];
NSURL *url = [NSURL URLWithString:[imgPath
stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];
//NSURL *url = [NSURL URLWithString:url];
[NSURLConnection sendAsynchronousRequest:[NSURLRequest requestWithURL:url]
queue:[NSOperationQueue currentQueue]
completionHandler:^(NSURLResponse * resp, NSData * data, NSError
* error)
{
if(error == NULL){
// here is our image
UIImage *image = [UIImage imageWithData:data];
cell1.imgThumbnail.image=image;
}
else{
cell1.imgThumbnail.image=[UIImage imageNamed:#"no preview 2.jpeg"];
}
}];
// NSURL *imageUrl = [NSURL URLWithString:imgPath];
// NSData *imageData = [NSData dataWithContentsOfURL:url];
// UIImage *image=[[UIImage alloc]initWithData:imageData];
// cell.imgThumbnail.image=image;
NSString *schedule =[[arrData objectAtIndex:indexPath.row]valueForKey:#"Schedule"];
NSArray *strings = [schedule componentsSeparatedByString:#","];
for (NSString *item in strings)
{
if ([item isEqualToString:#"Su"]) {
cell1.lblsu.textColor = [UIColor greenColor];
}else if ([item isEqualToString:#"Tu"]){
cell1.lblt.textColor = [UIColor greenColor];
}else if ([item isEqualToString:#"Th"]){
cell1.lblth.textColor = [UIColor greenColor];
}
else if ([item isEqualToString:#"M"]){
cell1.lblm.textColor = [UIColor greenColor];
}
else if ([item isEqualToString:#"F"]){
cell1.lblf.textColor = [UIColor greenColor];
}
else if ([item isEqualToString:#"S"]){
cell1.lbls.textColor = [UIColor greenColor];
}
else if ([item isEqualToString:#"W"]){
cell1.lblw.textColor = [UIColor greenColor];
}
}
cell1.lblname.text = [[arrData objectAtIndex:indexPath.row] valueForKey:#"Worker N
ame"];
cell1.lblexperience.text=[[arrData
objectAtIndex:indexPath.row]valueForKey:#"Experience"];
cell1.lblprizone.text=[[arrData objectAtIndex:indexPath.row]valueForKey:#"Primary
Zone"];
cell1.lblrate.text=[[arrData objectAtIndex:indexPath.row]valueForKey:#"Rate"];
return cell1;
}
}

Answer 1

I think it might be because you load your images by NSURLConnection sendAsynchronousRequest. Because the completitionhandler isn't called immediately, but when the data is returned to the request. So the images will be set after the cells are loaded.
Try to replace
[NSURLConnection sendAsynchronousRequest:[NSURLRequest requestWithURL:url]
queue:[NSOperationQueue currentQueue]
completionHandler:^(NSURLResponse * resp, NSData * data, NSError
* error)
{
if(error == NULL){
// here is our image
UIImage *image = [UIImage imageWithData:data];
cell1.imgThumbnail.image=image;
}
else{
cell1.imgThumbnail.image=[UIImage imageNamed:#"no preview 2.jpeg"];
}
}];
with code that will set imgThumbnail.image to an image that is in your project and see whether you still get radomly changing cells.

Answer 2

Problem: You are using dequeueReusableCellWithIdentifier so the same cell is reused when you are scrolling the tableview and you are send a AsynchronousRequest in that cell so the previously sent cell response we are receiving on another cell so it is showing different result.
For example: Cell 2 you are sending a request and then you scrolled the table view so the same cell is reused for cell 10 by that time you will receive the response of cell 2 send request and that image (response data) is displayed in cell 10.
Solution: send the request in separate method and save the images in array or dictionary then reload the corresponding cells based on the the received response.
For Example:EGOImageView is sending request asynchronously and saving in cache and displaying after receiving response please check that once

Answer 3

try this one ,for loading the images From webservices.
NSString *imgUrl = [[arrCategoryDetails objectAtIndex:indexPath.row]valueForKey:#"Image"];
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
NSData *imgData = [NSData dataWithContentsOfURL:[NSURL URLWithString:imgUrl]];
if (imgData) {
UIImage *image = [UIImage imageWithData:imgData];
if (image) {
dispatch_async(dispatch_get_main_queue(), ^{
CategoryDetailsTableCell *updateCell = (id)[tableView cellForRowAtIndexPath:indexPath];
if (updateCell)
updateCell.imgForCategoryDetailCell.image = image;
});
}
}
});