I am using GCD to load images from web into my UITableViewCell. But, wrong images are showing up.
Here is code:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
AppDelegate *appDelegate = [[UIApplication sharedApplication] delegate];
UITableViewCell *cell = [self.newsTable dequeueReusableCellWithIdentifier:#"newsTableCell"];
NSString *user = [usernames objectAtIndex:[indexPath row]];
NSString *stat = [statistics objectAtIndex:[indexPath row]];
NSString *imagePath = [appDelegate.URL stringByAppendingString:#"ImageName"];
UIImageView *userImageView = (UIImageView *)[self.view viewWithTag:80];
NSString *imagePath1 = [imagePath stringByAppendingString:[imagepaths objectAtIndex:[indexPath row]]];
NSURL *url = [NSURL URLWithString:imagePath1];
dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0ul);
dispatch_async(queue, ^{
NSData *data = [NSData dataWithContentsOfURL:url];
UIImage *img = [[UIImage alloc] initWithData:data];
userImageView.layer.cornerRadius = 5.0;
userImageView.layer.masksToBounds = YES;
dispatch_sync(dispatch_get_main_queue(), ^{
[userImageView setImage:img];
});
});
return cell
}
Please let me know, where I am going wrong.
You are not using at all your cell variable, you are setting images on an UIImageView which comes from self.view. The images will never be set correctly on the cells of the table.
Related
I am setting image on UITableViewCell using image url ,but the images doesn't get load unless i scrolls the UITableView.Here is the code that i have been using,i got to know about SDWeb Image library to download images from url,but i does;t want to use any library.Please tell me what aim doing wrong in this.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
// Configure the cell...
NSDictionary *dictCard=[cardsDetailsArray objectAtIndex:indexPath.row];
UILabel *nameLabel = (UILabel *)[cell viewWithTag:10];
UILabel *dateLabel = (UILabel *)[cell viewWithTag:11];
UIImageView *cellImage=(UIImageView *)[cell viewWithTag:0];
CGSize firstSize=CGSizeZero;
if([[dictCard objectForKey:#"orientation"]isEqualToString:#"1"]){
[cellImage setFrame:CGRectMake(0, 0, 75, 68)];
firstSize=CGSizeMake(75,68);
}
if([[dictCard objectForKey:#"orientation"]isEqualToString:#"0"]){
[cellImage setFrame:CGRectMake(0, 0, 107, 72)];
firstSize=CGSizeMake(107,72);
}
[cellImage setBackgroundColor:[UIColor clearColor]];
NSString *string=[dictCard objectForKey:#"email_sent"];
NSArray *items = [string componentsSeparatedByString:#","];
dateLabel.text=[dictCard objectForKey:#"date"];
nameLabel.text=[NSString stringWithFormat:#"Sent to %d People",[items count]];
NSURL* url = [NSURL URLWithString:(NSString *) [dictCard objectForKey:#"card_thumbnail"]];
NSURLRequest* request = [NSURLRequest requestWithURL:url];
[NSURLConnection sendAsynchronousRequest:request
queue:[NSOperationQueue mainQueue]
completionHandler:^(NSURLResponse * response,
NSData * data,
NSError * error) {
if (!error){
UIImage* image = [[UIImage alloc] initWithData:data];
//i am scaling the image here
UIImage *imageScale=[self imageWithImage:image scaledToSize:firstSize];
[cellImage setImage:imageScale];
}
}];
return cell;
}
I have also added [__tableViewDraft reloadData];after setting the cell image but due to this my cell keeps on changing its cell image.
Once the image has been downloaded, you need to ask iOS to refresh the cell. Check out reloadRowsAtIndexPaths:withRowAnimation:, among others.
Typically you might have have cells backed by CoreData objects and download and save the image to the managed object. You'd then have an NSFetchedResultsControllerDelegate trigger an update when the managed object changes, refreshing the row.
I have a uitableview and each cells have an image from facebook image profile and 2 uilabels (from singleton, not an internet request)
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath*)indexPath
{
static NSString *CellIdentifier = #"MenuCell";
MenuCellViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
if (cell == nil) {
cell = [[MenuCellViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
//Singleton
DataModel *m = [DataModel getModel];
switch ([indexPath section]) {
case 0: //Only Header
break;
case 1: //My cells
{
//If footer - set footer background
if (indexPath.row == [tableView numberOfRowsInSection:indexPath.section] - 1){
[cell setBackgroundView:[[UIImageView alloc]initWithImage:[UIImage imageNamed:#"imgFooter.png"]]];
//Else - set normal cell background
} else {
[cell setBackgroundView:[[UIImageView alloc]initWithImage:[UIImage imageNamed:#"img.png"]]];
}
//Get Facebook image
strForImg = [[NSString alloc] initWithFormat:#"https://graph.facebook.com/%#/picture?type=square",[[[m list] objectAtIndex:indexPath.row] objectForKey:#"id"]];
url =[NSURL URLWithString:strForImg];
img = [UIImage imageWithData: [NSData dataWithContentsOfURL:url]];
[cell.imgProfile setImage:img];
//Set some text (uilabels)
cell.lblNom.text = [[[m list] objectAtIndex:indexPath.row] objectForKey:#"name"];
cell.lblTour.text = [[[m list] objectAtIndex:indexPath.row] objectForKey:#"description"];
break;
}
}
}
This code is very slow and freezes the tableview as it loads from facebook the profile images of each cell dynamically.
I tried doing with a dispatch like this
case 1://My cells
{
if (indexPath.row == [tableView numberOfRowsInSection:indexPath.section] - 1){
[cell setBackgroundView:[[UIImageView alloc]initWithImage:[UIImage imageNamed:#"imgFooter.png"]]];
} else {
[cell setBackgroundView:[[UIImageView alloc]initWithImage:[UIImage imageNamed:#"img.png"]]];
}
dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0ul);
dispatch_async(queue, ^{
dispatch_sync(dispatch_get_main_queue(), ^{
strForImg = [[NSString alloc] initWithFormat:#"https://graph.facebook.com/%#/picture?type=square",[[list objectAtIndex:indexPath.row] objectForKey:#"id"]];
url =[NSURL URLWithString:strForImg];
img = [UIImage imageWithData: [NSData dataWithContentsOfURL:url]];
[cell.imgProfile setImage:img];
});
});
cell.lblNom.text = [[[m list] objectAtIndex:indexPath.row] objectForKey:#"name"];
cell.lblTour.text = [[[m list] objectAtIndex:indexPath.row] objectForKey:#"description"];
break;
}
The speed has slighty increased but it is still FREEZING when scrolling.
Is my dispatch not correct ? (I have just discovered it, maybe it is not well used).
Or is there any better method ?
I like the facebook friend picker. It puts a default profile image and refreshes the correct image profile when it is received from internet. How is this magic done ? :)
Fix this block:
dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0ul);
dispatch_async(queue, ^{
strForImg = [[NSString alloc] initWithFormat:#"https://graph.facebook.com/%#/picture?type=square",[[list objectAtIndex:indexPath.row] objectForKey:#"id"]];
url =[NSURL URLWithString:strForImg];
img = [UIImage imageWithData: [NSData dataWithContentsOfURL:url]];
dispatch_sync(dispatch_get_main_queue(), ^{
[cell.imgProfile setImage:img];
});
});
I'm using this code to load an image into my UITableView.
But nothing is loading, any ideas why? The link is correct when I NSLog it.
NSString *temp = [appointmentDictionaryTemp objectForKey:#"patient_small_photo_url"];
NSData * imageData = [NSData dataWithContentsOfURL:[NSURL URLWithString:temp]];
UIImage * image = [UIImage imageWithData:imageData];
UIImageView * myImageView = [[UIImageView alloc] initWithImage:image];
cell.patientImage = myImageView;
Update:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"appointmentCell";
AppointmentTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
NSDictionary *appointmentDictionaryTemp = [self.appointmentArray objectAtIndex:indexPath.row];
cell.patientNameLabel.text = [appointmentDictionaryTemp objectForKey:#"patient"];
cell.appointmentTimeLabel.text = [appointmentDictionaryTemp objectForKey:#"scheduled_time"];
NSString *urlString = [[appointmentDictionaryTemp objectForKey:#"patient_small_photo_url"] stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSData * imageData = [NSData dataWithContentsOfURL:[NSURL URLWithString:urlString]];
UIImage * image = [UIImage imageWithData:imageData];
cell.patientImage.image = image;
return cell;
}
Have you tried with:
cell.patientImage.image = image;
Of course you don't need to create myImageView.
Try adding percent escapes to your URL string.
NSString *urlString = [[appointmentDictionaryTemp objectForKey:#"patient_small_photo_url"] stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
I have tableView and need to load image from URL. I have an array that contains the URLs of images and when the page loads I need to load all the images into the tableview. Note that, not from a single URL, have an array with different URLs. How can I implement that? Please help
Thanks.
You can use GCD to load images in background thread, like this:
//get a dispatch queue
dispatch_queue_t concurrentQueue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
//this will start the image loading in bg
dispatch_async(concurrentQueue, ^{
NSData *image = [[NSData alloc] initWithContentsOfURL:imageURL];
//this will set the image when loading is finished
dispatch_async(dispatch_get_main_queue(), ^{
imageView.image = [UIImage imageWithData:image];
});
});
Hi. But you probably need to add a dispatch_release(concurrentQueue); to be sure no leak. – Franck Aug 25 at 19:43
You can use Lazy Loading when you want to download Images from internet
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
//All you reusable cell implementation here.
//Since your Images sizes differ. Keep a custom Imageview
if(![imagesForCategories containsObject:indexPath])
{
customImageView.image = [UIImage imageNamed:#"default-image.png"];
NSMutableArray *arr = [[NSArray alloc] initWithObjects:[imageUrlArray objectAtIndex:indexPath.row],indexPath, nil];
[self performSelectorInBackground:#selector(loadImageInBackground:) withObject:arr];
[arr release];
}
return cell;
}
- (void) loadImageInBackground:(NSArray *)urlAndTagReference
{
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
NSURL *imgUrl=[[NSURL alloc] initWithString:[urlAndTagReference objectAtIndex:0]];
NSData *imgData = [NSData dataWithContentsOfURL:imgUrl];
UIImage *img = [UIImage imageWithData:imgData];
[imgUrl release];
NSMutableArray *arr = [[NSMutableArray alloc ] initWithObjects:img,[urlAndTagReference objectAtIndex:1], nil ];
[self performSelectorOnMainThread:#selector(assignImageToImageView:) withObject:arr waitUntilDone:YES];
[arr release];
[pool release];
}
- (void) assignImageToImageView:(NSMutableArray *)imgAndTagReference
{
[imagesForCategories addObject:[imgAndTagReference objectAtIndex:1]];
UITableViewCell *cell = [celebCategoryTableView cellForRowAtIndexPath:[imgAndTagReference objectAtIndex:1]];
UIImageView *profilePic = (UIImageView *)[cell.contentView viewWithTag:20];
profilePic.image = [imgAndTagReference objectAtIndex:0];
}
You can use SDWebImage which permits very easy and speed loading of images in UITableView.
https://github.com/rs/SDWebImage
Try this code,imagearray contains urls of image
-(UITableViewCell *) tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
NSData* imageData = [[NSData alloc] initWithContentsOfURL:[NSURL URLWithString: [imagearray objectAtIndex:row]]];
UIImage* image = [[UIImage alloc] initWithData:imageData];
cell.imageView.image =image;
return cell;
}
You need to create your custom cell for lazy loading. This will allow you to download images correctly and without freezing. Here is nice example how to do this:
Asynch image loading
With afnetworki, it is too easy.
//afnetworking
#import "UIImageView+AFNetworking.h"
[cell.iboImageView setImageWithURL:[NSURL URLWithString:server.imagen] placeholderImage:[UIImage imageNamed:#"qhacer_logo.png"]];
I download some images using an NSThread. When all the images are downloaded, I have to put them in cell.myimageview. Give me the solution for setting an image in a user-defined method.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
TableCell *cell = (TableCell *)[TableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[TableCell alloc] initWithFrame:CGRectZero reuseIdentifier:CellIdentifier] autorelease];
}
NSString *bedsbaths=[NSString stringWithFormat:#"Beds:%# Baths:%#",[[AppDeleget.statuses valueForKey:#"beds"] objectAtIndex:indexPath.row],[[AppDeleget.statuses valueForKey:#"baths"] objectAtIndex:indexPath.row]];
cell.mlsno.text=[[AppDeleget.statuses valueForKey:#"mlsno"] objectAtIndex:indexPath.row];
cell.price.text=[[AppDeleget.statuses valueForKey:#"price"] objectAtIndex:indexPath.row];
cell.address.text=[[AppDeleget.statuses valueForKey:#"address"] objectAtIndex:indexPath.row];
cell.bedsbaths.text=bedsbaths;
cell.accessoryType=UITableViewCellAccessoryDetailDisclosureButton;
return cell;
}
-(void)LoadImage
{
for(int x=0;x<[ListPhotos count];x++)
{
NSData *imageData =[ListPhotos objectAtIndex:x];
id path = imageData;
NSURL *url = [NSURL URLWithString:path];
NSLog(#"%#",url);
NSData *data = [NSData dataWithContentsOfURL:url];
UIImage *img = [[UIImage alloc] initWithData:data];
[self performSelectorOnMainThread:#selector(downloadDone:) withObject:img waitUntilDone:NO];
}
}
-(void)downloadDone:(UIImage*)img {
// I have to set the cell here. How?
cell.myimageView.image=img
}
In -(void)LoadImage
Store the img in a NSArray.
In - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath , code as
cell.myimageView.image=[imgArray objectAtIndex:indexPath.row];
Assign the delegate and datasource of tableview as,
-(void)downloadDone:(UIImage*)img {
self.tableView.delegate=self;
self.tableView.datasource=self;
}