First image in my array is not displayed in collectionview cell - ios

- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath {
cell =[self.imgCllvw dequeueReusableCellWithReuseIdentifier:#"Cell" forIndexPath:indexPath];
if(!cell)
{
cell = [collectionView dequeueReusableCellWithReuseIdentifier:#"Cell" forIndexPath:indexPath];
}
NSDictionary *tmpDict = [images objectAtIndex:indexPath.row];
NSURL *url = [NSURL URLWithString:[tmpDict objectForKey:#"img"]];
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT,0), ^{
NSData *data = [NSData dataWithContentsOfURL:url];
UIImage *imge= [[UIImage alloc]initWithData:data];
dispatch_async(dispatch_get_main_queue(), ^{
cell.imageView.image = imge;
});
});
cell.layer.borderWidth=1.0f;
cell.layer.borderColor=[UIColor colorWithRed:215.0/255.0 green:214.0/255.0 blue:214.0/255.0 alpha:1.0].CGColor;
return cell;
}
First image is not loaded and if I scroll the collectionview images are displayed and I have used autolayout for collectionview

I think you should try async downloading of image rather than sync, something like this
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath {
cell =[self.imgCllvw dequeueReusableCellWithReuseIdentifier:#"Cell" forIndexPath:indexPath];
if(!cell)
{
cell = [collectionView dequeueReusableCellWithReuseIdentifier:#"Cell" forIndexPath:indexPath];
}
NSDictionary *tmpDict = [images objectAtIndex:indexPath.row];
NSURL *url = [NSURL URLWithString:[tmpDict objectForKey:#"img"]];
NSURLSessionTask *task = [[NSURLSession sharedSession] dataTaskWithURL:url completionHandler:^(NSData * _Nullable data, NSURLResponse * _Nullable response, NSError * _Nullable error) {
if (data) {
UIImage *image = [UIImage imageWithData:data];
if (image) {
dispatch_async(dispatch_get_main_queue(), ^{
MyCell *cell = (id)[collectionView cellForItemAtIndexPath:indexPath];
if (cell)
cell.imageView.image = image;
});
}
}
}];
[task resume];
cell.layer.borderWidth=1.0f;
cell.layer.borderColor=[UIColor colorWithRed:215.0/255.0 green:214.0/255.0 blue:214.0/255.0 alpha:1.0].CGColor;
return cell;
}

Instead of dispatch_async, mainqueue you can use dispatch_sync, like this,
dispatch_sync(dispatch_get_main_queue(), ^{
cell.imageView.image = imge;
});

Related

Multiple UICollectionView in one view update second UICollectionView data

I want to design as like image. I use two UICollectionView to design. But I can't update second UICollectionView data after click fast on UICollectionview row. I never think this is the correct way to do this. Any suggestion please. I need to do with Objective-C.
My Code:
- (NSInteger)collectionView:(UICollectionView *)view numberOfItemsInSection:(NSInteger)section
{
if (view.tag == 1) {
return 20;//SelfiThemeIm;age.count
} else {
return 15;
}
}
- (UICollectionViewCell *)collectionView:(UICollectionView *)cv cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
if (cv.tag == 0) {
TopCell *cell = [cv dequeueReusableCellWithReuseIdentifier:#"TopCell" forIndexPath:indexPath];
NSData * imageData = [[NSData alloc] initWithContentsOfURL: [NSURL URLWithString: SelfiThemeImage[indexPath.row]]];
cell.imageView.image = [UIImage imageWithData: imageData];
return cell;
} else {
BottomCell *cell = [cv dequeueReusableCellWithReuseIdentifier:#"BottomCell" forIndexPath:indexPath];
NSData * imageData = [[NSData alloc] initWithContentsOfURL: [NSURL URLWithString: SelfiThemePhysicalFileName[indexPath.row]]];
cell.imageView.image = [UIImage imageWithData: imageData];
return cell;
}
}
- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath
{
NSString *ThemeURL;
if (collectionView.tag == 1) {
ThemeURL = #"http://wap.shabox.mobi/sticker_app_server/content.aspx?catid=";
ThemeURL =[ThemeURL stringByAppendingString:[SelfiThemeImageContentCode objectAtIndex:indexPath.row]];
BottomCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:#"BottomCell" forIndexPath:indexPath];
AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];
[manager GET:ThemeURL
parameters:nil
success:^(AFHTTPRequestOperation *operation, id responseObject) {
NSString *array= [responseObject objectForKey:#"stickers"];
self.selfidata = array;
// NSLog(#"JSON responce Selfi: %#", self.selfidata);
for(int i=0; i<=self.selfidata.count-1; i++){
NSString *PhysicalFileName = #"http://wap.shabox.mobi/CMS/content/graphics/Stickers/D200x200/";
PhysicalFileName =[PhysicalFileName stringByAppendingString:[[self.selfidata objectAtIndex:i]objectForKey:#"PhysicalFileName"]];
PhysicalFileName =[PhysicalFileName stringByAppendingString:#".png"];
[SelfiThemePhysicalFileName addObject:[NSString stringWithFormat:PhysicalFileName]];
NSLog(#"PhysicalFileName Array - %#", PhysicalFileName);
}
NSLog(#"SelfiThemePhysicalFileName Array - %#", SelfiThemePhysicalFileName);
NSData * imageData = [[NSData alloc] initWithContentsOfURL: [NSURL URLWithString: SelfiThemePhysicalFileName[indexPath.row]]];
cell.imageView.image = [UIImage imageWithData: imageData];
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
NSLog(#"Error: %#", error);
}];
}else{
}
}
- (NSInteger)collectionView:(UICollectionView *)view numberOfItemsInSection:(NSInteger)section
{
if (view.tag == 1) {
return SelfiThemeImage.count;
} else {
return SelfiThemePhysicalFileName.count;
}
}
- (UICollectionViewCell *)collectionView:(UICollectionView *)cv cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
if (cv.tag == 0) {
TopCell *cell = [cv dequeueReusableCellWithReuseIdentifier:#"TopCell" forIndexPath:indexPath];
NSData * imageData = [[NSData alloc] initWithContentsOfURL: [NSURL URLWithString: SelfiThemeImage[indexPath.row]]];
cell.imageView.image = [UIImage imageWithData: imageData];
return cell;
} else {
BottomCell *cell = [cv dequeueReusableCellWithReuseIdentifier:#"BottomCell" forIndexPath:indexPath];
NSData * imageData = [[NSData alloc] initWithContentsOfURL: [NSURL URLWithString: SelfiThemePhysicalFileName[indexPath.row]]];
cell.imageView.image = [UIImage imageWithData: imageData];
return cell;
}
}
- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath
{
NSString *ThemeURL;
if (collectionView.tag == 1) {
ThemeURL = #"http://wap.shabox.mobi/sticker_app_server/content.aspx?catid=";
ThemeURL =[ThemeURL stringByAppendingString:[SelfiThemeImageContentCode objectAtIndex:indexPath.row]];
BottomCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:#"BottomCell" forIndexPath:indexPath];
AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];
[manager GET:ThemeURL
parameters:nil
success:^(AFHTTPRequestOperation *operation, id responseObject) {
NSString *array= [responseObject objectForKey:#"stickers"];
self.selfidata = array;
// NSLog(#"JSON responce Selfi: %#", self.selfidata);
for(int i=0; i<=self.selfidata.count-1; i++){
NSString *PhysicalFileName = #"http://wap.shabox.mobi/CMS/content/graphics/Stickers/D200x200/";
PhysicalFileName =[PhysicalFileName stringByAppendingString:[[self.selfidata objectAtIndex:i]objectForKey:#"PhysicalFileName"]];
PhysicalFileName =[PhysicalFileName stringByAppendingString:#".png"];
[SelfiThemePhysicalFileName addObject:[NSString stringWithFormat:PhysicalFileName]];
NSLog(#"PhysicalFileName Array - %#", PhysicalFileName);
}
NSLog(#"SelfiThemePhysicalFileName Array - %#", SelfiThemePhysicalFileName);
[self.myCollectionView reloadData];
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
NSLog(#"Error: %#", error);
}];
}else{
}
}
I made changes in your code that just replace it with your code .
Happy Coding. give vote and approve it
Thank You.
You need have 2 objects referring CollectioView lets say _collectionView1 and _collectionView1.
Now make sure delegate for these 2 is set to self
in -(void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath check
if ([collectionView isEqualTo:_collectionView1]) {
_collectionView2DataSource = ;//Do your calculation and setting
[_collectionView2 reloadData] ;
}
I am considering you have populated initial value and you are aware of all collection-view datasource and delegate functioning.
If you have the 2nd collectionview in storyboard/xib file, create the IBOUTLET for that collectionview and name it "what_ever_name_you_want"
if you have created this programatically, make the collectionview a global variable in the class
in didSelect method reload the collection view by calling ["what_ever_name_you_gave" reloadData];
you need to change this line because this line create new cell instance .
BottomCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:#"BottomCell" forIndexPath:indexPath];
change with :
BottomCell *cell = [collectionView cellForItemAtIndexPath:indexPath];

asynchronous image downloading in tabelviewcell?

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"cell";
TVcell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[TVcell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
cell.titleLabel.text = [[[arrayData objectAtIndex:indexPath.row]valueForKey:#"title"]stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
cell.txtlabel.text = [[[arrayData objectAtIndex:indexPath.row] valueForKey:#"description"]stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
cell.tag = indexPath.row;
cell.imageView.image = nil;
dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0ul);
dispatch_async(queue, ^(void) {
NSData *imageData = [NSData dataWithContentsOfURL:[NSURL URLWithString:[enclosureUrlArray objectAtIndex:indexPath.row]]];
UIImage* image = [[UIImage alloc] initWithData:imageData];
if (image) {
dispatch_async(dispatch_get_main_queue(), ^{
if (cell.tag == indexPath.row) {
cell.IMGLabel.image = image;
[cell setNeedsLayout];
}
});
}
});
return cell;
}
while i'm scrolling that same images are appearing on the cells,which cells im reusing.i used scroll view delegate also.im storing urls in enclosureUrlArray and i'm passing.
Put cell.IMGLabel.image = nil in your cellForRowAtIndexPath before downloading image, i.e. below cell.imageView.image = nil; this line.
Or set some place holder image (no image available kind of image to cell's image in interface builder), so if image is not downloaded then it will show this place holder image otherwise it will show downloaded image.
SDWebImage is good for this kind of case. It will cache the images so it will give better performance also. There is nothing wrong to use any good third party library.
By using SDWeb image:
#import <SDWebImage/UIImageView+WebCache.h>
...
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *MyIdentifier = #"MyIdentifier";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:MyIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault
reuseIdentifier:MyIdentifier] autorelease];
}
// Here we use the new provided sd_setImageWithURL: method to load the web image
[cell.imageView sd_setImageWithURL:[NSURL URLWithString:#"http://www.domain.com/path/to/image.jpg"]
placeholderImage:[UIImage imageNamed:#"placeholder.png"]];
cell.textLabel.text = #"My Text";
return cell;
}
You can also use NSURLSession as well,see this link
Async image loading from url inside a UITableView cell - image changes to wrong image while scrolling
NSURL *url = [NSURL URLWithString:[enclosureUrlArray objectAtIndex:indexPath.row]];
NSURLSessionTask *task = [[NSURLSession sharedSession] dataTaskWithURL:url completionHandler:^(NSData * _Nullable data, NSURLResponse * _Nullable response, NSError * _Nullable error) {
if (data) {
UIImage *image = [UIImage imageWithData:data];
if (image) {
dispatch_async(dispatch_get_main_queue(), ^{
MyCell *updateCell = (id)[tableView cellForRowAtIndexPath:indexPath];
if (updateCell)
updateCell.IMGLabel.image = image;
});
}
}
}];
[task resume];
works perfect for me..
with the help of sdwebimage you can show the image like this:-
NSString *string2 = [[businessListArray objectAtIndex:indexPath.row ]valueForKey:#"logo"];
NSURL *url1 = [NSURL URLWithString:
[NSString stringWithFormat:
#"%#%#",
#"http://dev-demo.info.bh-in-15./upload/post/",
string2]];
UIImageView *imageView = (UIImageView *)[cell.contentView viewWithTag:301];
[imageView sd_setImageWithURL:url1
placeholderImage:[UIImage imageNamed:#"pocket.png"]
completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType, NSURL *imageURL) {
imageView.image = image;
}];

Async image loading from url inside a UITableView cell - image changes to wrong image while scrolling?

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{ static NSString *CellIdentifier = #"cell";
TVcell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
if (cell == nil)
cell = [[TVcell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
cell.txtlabel.text = [[[arrayData objectAtIndex:indexPath.row] valueForKey:#"description"]stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
cell.IMGLabel.contentMode = UIViewContentModeScaleAspectFill;
cell.IMGLabel.image = nil;
NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:#"%#",[enclosureUrlArray objectAtIndex:indexPath.row]]];
NSURLSessionTask *task = [[NSURLSession sharedSession] dataTaskWithURL:url completionHandler:^(NSData * _Nullable data, NSURLResponse * _Nullable response, NSError * _Nullable error) {
if (data) {
UIImage *image = [UIImage imageWithData:data];
if (image) {
dispatch_async(dispatch_get_main_queue(), ^{
cell.IMGLabel.image = image;
[cell.IMGLabel setImage:image];
[cell.IMGLabel.layer setMasksToBounds:YES];
[cell.IMGLabel.layer setCornerRadius:2.5f];
[cell setNeedsLayout];
});
}
}
}];
[task resume];
Your problem is that you have no guarantee that your NSUrlRequests will terminate in the same order than they started. This is bad because your cells are re-used for better performance and it can end with strange behavior.
You can find a fix here: Asynchronous downloading of images for UITableView with GCD
Or you can use tools listed here to help you address this issue: https://stackoverflow.com/a/32601838/3769338

Images in cell are changing everytime when tableview is scrolled

In the below code whenever I am scrolling the tableview, images in each cell are changing, which shouldn't happen. Please help. Thanks in advance.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
UserDetails *userDetails = [arrUserDetails objectAtIndex:indexPath.row];
static NSString *CellIdentifier = #"CustomCell";
__weak TableViewCell *cell = (TableViewCell *)[_tableViewUsername dequeueReusableCellWithIdentifier:CellIdentifier];
cell.tag = indexPath.row;
cell.userName.text = userDetails.userName;
[self.operationQueue addOperationWithBlock: ^ {
NSURL *aURL = [NSURL URLWithString:userDetails.userImageURL];
NSError *error = nil;
NSData *data = [NSData dataWithContentsOfURL:aURL options:nil error:&error];
UIImage *image = nil;
if (cell.tag == indexPath.row)
{
image = [UIImage imageWithData:data];
[[NSOperationQueue mainQueue] addOperationWithBlock: ^ {
cell.customImageView.image = image;
cell.customImageView.contentMode = UIViewContentModeScaleToFill;
cell.accessoryType = UITableViewCellAccessoryCheckmark;
}];
}
}];
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
UserDetails *userDetails = [arrUserDetails objectAtIndex:indexPath.row];
static NSString *CellIdentifier = #"CustomCell";
__weak TableViewCell *cell = (TableViewCell *)[_tableViewUsername dequeueReusableCellWithIdentifier:CellIdentifier];
cell.tag = indexPath.row;
cell.userName.text = userDetails.userName;
//Add Default placeholder
cell.customImageView.image = [UIImage imageNamed:#"Default.png"];
[self.operationQueue addOperationWithBlock: ^ {
NSURL *aURL = [NSURL URLWithString:userDetails.userImageURL];
NSError *error = nil;
NSData *data = [NSData dataWithContentsOfURL:aURL options:nil error:&error];
UIImage *image = nil;
if (cell.tag == indexPath.row)
{
image = [UIImage imageWithData:data];
[[NSOperationQueue mainQueue] addOperationWithBlock: ^ {
cell.customImageView.image = image;
cell.customImageView.contentMode = UIViewContentModeScaleToFill;
cell.accessoryType = UITableViewCellAccessoryCheckmark;
}];
}
}];
Add Default placeholder for image before loading it from url,As cells are being reused it takes the previous image
You can use SDWebImage.framework to load image
[cell.customImageView sd_setImageWithURL:[NSURL URLWithString:userDetails.userImageURL] placeholderImage:nil options:SDWebImageCacheMemoryOnly completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType, NSURL *imageURL) {
if (image) {
[cell.customImageView setImage:image];
}
}];
You can use Afnetworking class for this .
Simply import #import "UIImageView+AFNetworking.h"
And use this line:-
[cell.imgProfile setImageWithURL:imgurl placeholderImage:[UIImage imageNamed:#""]];
Imgurl is the image Url which you are getting from response

how to loading images using Asynchronous GCD For UITableviewcell/

I'm loading images for my uitableview asynchronously using GCD, but there is a problem - when scrolling down UITableview the images are dissappeared on top.And sometimes the images are not displayed in UITableviewcell. This is my code.please give me any idea.Is there any error in my code.Please help me.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *identifier=#"cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:identifier];
if (cell == nil)
{
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:#"identifier"];
}
image=[[UIImageView alloc]initWithFrame:CGRectMake(0, 0, 300, 80)];
[cell.contentView addSubview:image];
str=att.classimage;
url=#"My URL";
if(str!=nil){
dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0ul);
dispatch_async(queue, ^(void) {
dispatch_async(dispatch_get_main_queue(), ^{
NSString *imageStr=[url stringByAppendingString:str];
image.image = [UIImage imageNamed:imageStr];
});
});
image.image=[UIImage imageNamed:#"nav-bar-logo.png"];
}
return cell;
}
Before setting Image check if that cell is still in memory.
UITableViewCell *updateCell = (id)[tableView cellForRowAtIndexPath:indexPath];
if (updateCell)
{
yourImageView.image = [imagePost fixOrientation];
}
I am doing similar thing, but Using NSURLConnection.
NSURL *postImage = [NSURL URLWithString:#"Your URL"];
NSMutableURLRequest *imageRequest = [[NSMutableURLRequest alloc]initWithURL:postImage cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:30];
[imageRequest setHTTPMethod:#"GET"];
[NSURLConnection sendAsynchronousRequest:imageRequest queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *error)
{
imagePost = [UIImage imageWithData:data]; // UIImage Object
UITableViewCell *updateCell = (id)[tableView cellForRowAtIndexPath:indexPath];
if (updateCell)
{
postImageView.image = [imagePost fixOrientation];// setting my ImageView
}
}];
Hope this will help you.
You can use AFNetworknig for showing images from remote URL.
get AFNetworking from here
just
#import "AFNetworking.h"
[imageView setImageWithURL:url placeholderImage:[UIImage imageNamed:#"placeHolderImage"]];
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *identifier=#"cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:identifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:identifier];
UIImageView *imageView =[[UIImageView alloc]initWithFrame:CGRectMake(0, 0, 300, 80)];
imageView.tag = 100;
[cell.contentView addSubview:imageView];
}
str=att.classimage;
url=#"My URL";
UIImageView *cellImageView = [cell.contentView viewWithTag:100];
cellImageView.image = nil;
if(str!=nil) {
dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0ul);
dispatch_async(queue, ^(void) {
NSString *imageStr = [url stringByAppendingString:str];
UIImage *image = [UIImage imageWithData:[NSData dataWithContentsOfURL:[NSURL URLWithString:imageStr]]];
dispatch_async(dispatch_get_main_queue(), ^{
cellImageView.image = image;
});
});
}
return cell;
}

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