I want to have a similar functionality as in the Photos app on the iPhone in my Scrollview. So I've added all images to my scrollview like this and it works nicely.
-(void)prepareScrollView
{
for(int i =0;i<[self.layoverPhotoAssets count];i++){
PHAsset *asset = self.layoverPhotoAssets[i];
UIImageView *imageView = [[UIImageView alloc] init];
int x = self.scrollView.frame.size.width * i;
imageView.frame = CGRectMake(x, 0, self.scrollView.frame.size.width, self.scrollView.frame.size.height);
imageView.contentMode = UIViewContentModeScaleAspectFit;
PHImageRequestOptions *options = [[PHImageRequestOptions alloc] init];
options.resizeMode = PHImageRequestOptionsResizeModeFast;
options.deliveryMode = PHImageRequestOptionsDeliveryModeHighQualityFormat; //I only want the highest possible quality
options.synchronous = NO;
options.networkAccessAllowed = YES;
[[PHImageManager defaultManager] requestImageForAsset:asset targetSize:self.scrollView.frame.size contentMode:PHImageContentModeAspectFill options:options resultHandler:^(UIImage *result, NSDictionary *info) {
dispatch_async(dispatch_get_main_queue(), ^{
if(result){
imageView.image = result;
}
});
}];
[self.scrollView setContentSize:CGSizeMake(self.scrollView.frame.size.width * (i + 1), self.scrollView.frame.size.height)];
//self.scrollView.contentSize= ;
[self.scrollView addSubview:imageView];
}
}
However I have 2 questions:
1. Like this, all images will be loaded at once. Memory wise this is quite bad. How can I improve that without worsening the user experience?
2. How can I make the image itself zoomable?
Related
What am I missing? The inner scrollview and the image view fill the entire screen. But somehow my image is not centered. The top left corner of the image starts in the center of the view, but I would like to have the image nicely centered. Also during zooming.
-(void)prepareScrollView
{
for(int i =0;i<[self.layoverPhotoAssets count];i++){
PHAsset *asset = self.layoverPhotoAssets[i];
FMImageZoomViewController *zoomController = [[FMImageZoomViewController alloc] init];
// UIImageView *imageView = [[UIImageView alloc] init];
int x = self.scrollView.frame.size.width * i;
zoomController.view.frame = CGRectMake(x, 0, self.scrollView.frame.size.width, self.scrollView.frame.size.height);
//zoomController.view.frame = CGRectMake(0,0,self.view.bounds.size.width,self.view.bounds.size.height);
[self.scrollView addSubview:zoomController.view];
zoomController.zoomScroller.delegate = self;
zoomController.imageView.tag = 1;
[self.zoomControllers addObject:zoomController];
PHImageRequestOptions *options = [[PHImageRequestOptions alloc] init];
options.resizeMode = PHImageRequestOptionsResizeModeFast;
options.deliveryMode = PHImageRequestOptionsDeliveryModeHighQualityFormat; //I only want the highest possible quality
options.synchronous = NO;
options.networkAccessAllowed = YES;
[[PHImageManager defaultManager] requestImageForAsset:asset targetSize:zoomController.zoomScroller.frame.size contentMode:PHImageContentModeAspectFill options:options resultHandler:^(UIImage *result, NSDictionary *info) {
dispatch_async(dispatch_get_main_queue(), ^{
if(result){
zoomController.imageView.image = result;
zoomController.imageView.backgroundColor = [UIColor redColor];
}
});
}];
//self.scrollView.contentSize= ;
}
[self.scrollView setContentSize:CGSizeMake(self.scrollView.frame.size.width * [self.layoverPhotoAssets count], 0)];
[self scrollToAsset:self.selectedAsset];
}
Consider:
zoomController.view.frame = CGRectMake(x, 0, self.scrollView.frame.size.width, self.scrollView.frame.size.height);
[self.scrollView addSubview:zoomController.view];
That cannot be right. If zoomController.view is to be a subview of self.scrollView, its frame within self.scrollView is in terms of the bounds of self.scrollView, not the frame of self.scrollView.
Solved it like this:
-(void)prepareScrollView
{
for(int i =0;i<[self.layoverPhotoAssets count];i++){
PHAsset *asset = self.layoverPhotoAssets[i];
FMImageZoomViewController *zoomController = [[FMImageZoomViewController alloc] init];
// UIImageView *imageView = [[UIImageView alloc] init];
int x = self.scrollView.frame.size.width * i;
zoomController.view.frame = CGRectMake(x, 0, self.scrollView.bounds.size.width, self.scrollView.bounds.size.height);
//zoomController.view.frame = CGRectMake(0,0,self.view.bounds.size.width,self.view.bounds.size.height);
[self.scrollView addSubview:zoomController.view];
zoomController.zoomScroller.delegate = self;
[self.zoomControllers addObject:zoomController];
PHImageRequestOptions *options = [[PHImageRequestOptions alloc] init];
options.resizeMode = PHImageRequestOptionsResizeModeExact;
options.deliveryMode = PHImageRequestOptionsDeliveryModeHighQualityFormat; //I only want the highest possible quality
options.synchronous = NO;
options.networkAccessAllowed = YES;
[[PHImageManager defaultManager] requestImageForAsset:asset targetSize:zoomController.zoomScroller.bounds.size contentMode:PHImageContentModeAspectFit options:options resultHandler:^(UIImage *result, NSDictionary *info) {
dispatch_async(dispatch_get_main_queue(), ^{
if(result){
zoomController.imageView = [[UIImageView alloc] initWithImage:result];
zoomController.imageView.frame = zoomController.zoomScroller.bounds;
[zoomController.imageView setContentMode:UIViewContentModeScaleAspectFit];
zoomController.imageView.clipsToBounds = YES;
[zoomController.imageView setCenter: self.scrollView.center];
zoomController.imageView.tag = 1;
[zoomController.zoomScroller addSubview:zoomController.imageView];
// zoomController.imageView.contentMode = UIViewContentModeCenter;
// if (zoomController.imageView.bounds.size.width > result.size.width && zoomController.imageView.bounds.size.height > result.size.height) {
// zoomController.imageView.contentMode = UIViewContentModeScaleAspectFit;
// }
}
});
}];
//self.scrollView.contentSize= ;
}
[self.scrollView setContentSize:CGSizeMake(self.scrollView.frame.size.width * [self.layoverPhotoAssets count], 0)];
[self scrollToAsset:self.selectedAsset];
}
When I apply CIFilters to images the memory usage keeps growing and I don't know what to do.
I've tried everything I could:
using #autoreleasepool:
- (UIImage *)applySepiaToneTo:(UIImage *)img //Sepia
{
#autoreleasepool
{
CIImage *ciimageToFilter = [CIImage imageWithCGImage:img.CGImage];
CIFilter *sepia = [CIFilter filterWithName:#"CISepiaTone"
keysAndValues: kCIInputImageKey, ciimageToFilter,
#"inputIntensity", #1.0, nil];
return [self retrieveFilteredImageWithFilter:sepia];
}
}
- (UIImage *)retrieveFilteredImageWithFilter:(CIFilter *)filtro
{
#autoreleasepool
{
CIImage *ciimageFiltered = [filtro outputImage];
CGImageRef cgimg = [_context createCGImage:ciimageFiltered
fromRect:[ciimageFiltered extent]];
UIImage *filteredImage = [UIImage imageWithCGImage:cgimg];
CGImageRelease(cgimg);
return filteredImage;
}
}
I'm also downsizing the image to be filtered and doing the filtering in a background thread:
- (void)filterWasSelected:(NSNotification *)notification
{
self.darkeningView.alpha = 0.5;
self.darkeningView.userInteractionEnabled = YES;
[self.view bringSubviewToFront:self.darkeningView];
[self.activityIndic startAnimating];
[self.view bringSubviewToFront:self.activityIndic];
int indice = [notification.object intValue];
__block NSArray *returnObj;
__block UIImage *auxUiimage;
if(choosenImage.size.width == 1280 || choosenImage.size.height == 1280)
{
UIImageView *iv;
if(choosenImage.size.width >= choosenImage.size.height)
{
float altura = (320 * choosenImage.size.height)/choosenImage.size.width;
iv = [[UIImageView alloc] initWithFrame:CGRectMake(0,0,320,altura)];
iv.image = choosenImage;
}
else
{
float largura = (choosenImage.size.width * 320)/choosenImage.size.height;
iv = [[UIImageView alloc] initWithFrame:CGRectMake(0,0,largura,320)];
iv.image = choosenImage;
}
UIGraphicsBeginImageContextWithOptions(iv.bounds.size, YES, 0.0);
[iv.layer renderInContext:UIGraphicsGetCurrentContext()];
auxUiimage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
}
else
auxUiimage = choosenImage;
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_BACKGROUND, 0), ^{
if(artisticCollection)
returnObj = [self.filterCoordinator setupFilterArtisticType:indice toImage:auxUiimage];
else
returnObj = [self.filterCoordinator setupFilterOldOrVintageType:indice toImage:auxUiimage];
dispatch_async(dispatch_get_main_queue(), ^{
self.darkeningView.alpha = 0.3;
self.darkeningView.userInteractionEnabled = NO;
[self.activityIndic stopAnimating];
[self.view bringSubviewToFront:stageBackground];
[self.view bringSubviewToFront:stage];
[self.view bringSubviewToFront:self.filtersContainerView];
[self.view bringSubviewToFront:self.framesContainerView];
[self.view bringSubviewToFront:self.colorsContainerView];
if(returnObj)
{
auxUiimage = [returnObj firstObject];
NSLog(#"filtered image width = %f and height = %f", auxUiimage.size.width, auxUiimage.size.height);
returnObj = nil;
choosenImageContainer.image = auxUiimage;
}
});
});
}
I've also tried creating the context using the contextWithEAGLContext method, nothing changed.
I've researched a lot including stack overflow and found nothing.
Until I place the image in the image view (the image comes from the photo album) I'm only using 23 mega of memory, when I apply a filter, the use jumps to 51 mega and does not comes down. If I continue to apply other filters the memory usage only grows.
There's no linking in my app, I've checked in Instruments.
Also the bringSubviewToFront methods are not responsible, I've checked.
It's in the creation of the CIImage followed by the creation of the CIFilter object.
I know that in the process of applying the filter data is loaded into memory, but how to clean the memory after applying the filter?
Is there any secret that I'm not aware of?? Please help
I have UIScrollView that contains images from the server.
I should put Activity Indicator while the image is currently loading.
UIScrollView contains dynamic number of images from the server.
May I know how can I add activity indicators on each page while the image is loading and remove once image is loaded.
Here's my code to retrieve images:
NSDictionary *items = [NSDictionary dictionaryWithObject:dictInfo forKey:#"images"];
imageList = [items objectForKey:#"images"];
NSArray *img = [imageList objectForKey:#"list"];
NSInteger imgCount = [img count];
buttonArray = [[NSMutableArray alloc] init];
for (int i=0; i<imgCount; i++) {
NSDictionary *imgDict = [img objectAtIndex:i];
// REQUEST FOR IMAGES
NSString *imgPath = [imgDict objectForKey:#"image_slot"];
NSString *imgURL = imgPath;
__block ASIHTTPRequest *requestImage = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:imgURL]];
[requestImage setCompletionBlock:^{
imgView = [UIImage imageWithData:[requestImage responseData]];
if (imgURL.length) {
[pendingRequests removeObjectForKey:imgURL];
}
scrollView.userInteractionEnabled = YES;
scrollView.exclusiveTouch = YES;
scrollView.canCancelContentTouches = YES;
scrollView.delaysContentTouches = YES;
scrollView.bounces = NO;
CGRect frame;
frame.origin.x = self.scrollView.frame.size.width * i;
frame.origin.y = 0;
frame.size = self.scrollView.frame.size;
SWTUIButton *imgBtn = [[SWTUIButton alloc] initWithFrame:frame];
imgBtn.url = [requestImage.userInfo objectForKey:#"rURL"];
[imgBtn setImage:imgView forState:UIControlStateNormal];
imgBtn.backgroundColor = [UIColor clearColor];
[imgBtn addTarget:self action:#selector(buttonpushed:) forControlEvents:UIControlEventTouchUpInside];
[scrollView addSubview:imgBtn];
[buttonArray addObject:imgBtn];
[imgBtn release];
self.scrollView.contentSize = CGSizeMake(self.scrollView.frame.size.width * img.count, self.scrollView.frame.size.height);
}];
I highly suggest you use NINetworkImageView from https://github.com/jverkoey/nimbus project.
It's very light and useful.
It has a delegate method to let you know when an image is loaded.
What you basically need to do is:
1. create an NINetworkImageView for each page, just like you do with UIImageView, and call set
NINetworkImageView* networkImageView = [[[NINetworkImageView alloc] initWithImage:initialImage]
autorelease];
networkImageView.delegate = self;
networkImageView.contentMode = UIViewContentModeCenter;
[networkImageView setPathToNetworkImage:
#"http://farm3.static.flickr.com/2484/3929945380_deef6f4962_z.jpg"
forDisplaySize: CGSizeMake(kImageDimensions, kImageDimensions)];
https://github.com/jverkoey/nimbus/tree/master/examples/photos/NetworkPhotoAlbums
the add the indicator to the networkImageView as a subview.
implement the delegate as follows:
-(void)networkImageView:(NINetworkImageView *)imageView didLoadImage:(UIImage *)image {
[imageView removeAllSubviews];
}
the end result would be a much smaller code for doing the same thing.
I'm parsing my data on this way:
NSDictionary *item = [tableData objectAtIndex:[indexPath row]];
[[cell textLabel] setText:[item objectForKey:#"title"]];
[[cell detailTextLabel] setText:[item objectForKey:#"description"]];
But is there a way to parse an cell image? Normally it's
UIImage *cellImage = [UIImage imageNamed:#"image.png"];
cell.imageView.image = cellImage;
But i'm searching for a way like
[[cell UIImage cellimage] ....
Something like that so i can parse an image url from json in it
is that possible?
NSURL *url = [NSURL URLWithString:[item objectForKey:#"image"]];
NSData *data = [NSData dataWithContentsOfURL:url];
cell.imageView.image = [UIImage imageWithData:data];
Set a max width for the image
- (void)searchBarSearchButtonClicked:(UISearchBar *)searchBar // called when keyboard search button pressed
{
[spinner startAnimating];
spinner.hidden=NO;
NSLog( #" Searchbar text = %#",searchBar.text);
strSearch=searchBar.text;
strSearch=[strSearch stringByReplacingOccurrencesOfString:#" " withString:#"+"];
[searchBar resignFirstResponder];
[self searchGooglePhotos];
}
- (void)searchBarCancelButtonClicked:(UISearchBar *) searchBar // called when cancel button pressed
{
[searchBar resignFirstResponder];
}
-(void)searchGooglePhotos
{
// Build the string to call the Flickr API
NSString *urlString = [NSString stringWithFormat:#"http://ajax.googleapis.com/ajax/services/search/images?v=1.0&q=%#",strSearch];
NSLog(#"urlarrystring is := %#",urlString);
// Create NSURL string from formatted string
NSURL *url = [NSURL URLWithString:urlString];
// Setup and start async download
NSURLRequest *request = [[NSURLRequest alloc] initWithURL: url];
NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
[connection release];
[request release];
}
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
// Store incoming data into a string
NSString *jsonString = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
// Create a dictionary from the JSON string
NSDictionary *respone = [jsonString JSONValue];
//NSLog(#"result dict is :%#",respone);
// Build an array from the dictionary for easy access to each entry
urlarry = [[[respone valueForKey:#"responseData"] valueForKey:#"results"]valueForKey:#"url"];
NSArray *title = [[[respone valueForKey:#"responseData"] valueForKey:#"results"]valueForKey:#"title"];
MoreUrlarry=[[[respone valueForKey:#"responseData"] valueForKey:#"cursor"]valueForKey:#"moreResultsUrl"];
[urlarry retain];
NSLog(#"photourlarry is :%#",urlarry);
NSLog(#"phototitle is :%#",title);
NSLog(#"photoMoreUrlarry is :%#",MoreUrlarry);
NSData *data2;
NSString *str=[[NSString alloc] init];
[scrl removeFromSuperview];
[displayview removeFromSuperview];
scrl=[[UIScrollView alloc] initWithFrame:CGRectMake(0, 44,320, 430)];
[scrl setContentSize:CGSizeMake(320*[urlarry count], 430)];
scrl.pagingEnabled=YES;
//==========
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
// Assign activity indicator to the pre-defined property (so it can be removed when image loaded)
//self.activityIndicator = [[UIActivityIndicatorView alloc] initWithFrame:CGRectMake(55, 67, 25, 25)];
// Start it animating and add it to the view
// Create multiple imageviews to simulate a 'real' application with multiple images
CGFloat verticalPosition = 10;
int i = 1;
for (i=1; i<5; i++) {
// Set vertical position of image in view.
if (i > 1) {
verticalPosition = verticalPosition+85;
}
UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake(122, verticalPosition, 80, 80)];
imageView.tag = i;
[self.view addSubview:imageView];
// set the image to be loaded (using the same one here but could/would be different)
NSString *str123=[urlarry objectAtIndex:i-1];
NSURL *imgURL = [NSURL URLWithString:str123];
// Create an array with the URL and imageView tag to
// reference the correct imageView in background thread.
NSMutableArray *arr = [[NSArray alloc] initWithObjects:imgURL, [NSString stringWithFormat:#"%d", i], nil ];
// Start a background thread by calling method to load the image
[self performSelectorInBackground:#selector(loadImageInBackground:) withObject:arr];
}
[pool release];
/*
int x=10,y=50,p=250,q=20;
for (int i=0; i<[urlarry count]; i++)
{
str=[NSString stringWithString:[urlarry objectAtIndex:i]];
data2 = [NSData dataWithContentsOfURL:[NSURL URLWithString:str]];
Favimage = [[UIImage alloc]initWithData:data2];
markButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[markButton setFrame:CGRectMake(p, q, 35,20)];
markButton.tag=i;
NSLog(#"tag is :%d",markButton.tag);
//[imgButton setTitle:[NSString stringWithFormat:#"%i",i] forState:UIControlStateNormal];
//imgButton.contentMode=UIViewContentModeScaleAspectFit;
// [imgButton setBackgroundImage:[UIImage imageNamed:#"no.png"]forState:UIControlStateNormal];
//[imgButton setImage:[Favimage imageScaledToFitSize:CGSizeMake(300, 320)] forState:UIControlStateNormal];
[markButton addTarget:self action:#selector(mark_buttonPressed:) forControlEvents:UIControlEventTouchUpInside];
[scrl addSubview:markButton];
UIButton *imgButton = [UIButton buttonWithType:UIButtonTypeCustom];
[imgButton setFrame:CGRectMake(x, y, 300,320)];
imgButton.tag=i;
NSLog(#"tag is :%d",imgButton.tag);
//[imgButton setTitle:[NSString stringWithFormat:#"%i",i] forState:UIControlStateNormal];
imgButton.contentMode=UIViewContentModeScaleAspectFit;
// [imgButton setBackgroundImage:[UIImage imageNamed:#"no.png"]forState:UIControlStateNormal];
[imgButton setImage:[Favimage imageScaledToFitSize:CGSizeMake(300, 320)] forState:UIControlStateNormal];
[imgButton addTarget:self action:#selector(buttonPressed:) forControlEvents:UIControlEventTouchUpInside];
//[imgButton setImage:Favimage forState:UIControlStateNormal];
[scrl addSubview:imgButton];
//UIImageView *imageview=[[UIImageView alloc] initWithFrame:CGRectMake(x, y, 90, 90)];
// [imageview setImage:Favimage];
// [scrl addSubview:imageview];
NSLog(#"value of x=%d",x);
NSLog(#"value of y=%d",y);
NSLog(#"value of p=%d",p);
NSLog(#"value of q=%d",q);
NSLog(#"str is : %#",str);
if (y>=30 )
{
//x=15;
x=x+320;
}
if (q>=0 )
{
//x=15;
p=p+320;
}
//else
// {
// y=y+;
// }
}*/
[spinner stopAnimating];
spinner.hidden=TRUE;
[self.view addSubview:scrl];
btnmore.hidden=NO;
//NSLog(#"str is : %#",str);
// NSLog(#"j is : %d",j);
// NSLog(#"p is : %d",p);
}
- (void) loadImageInBackground:(NSArray *)urlAndTagReference {
NSLog(#"Received URL for tagID: %#", urlAndTagReference);
// Create a pool
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
// Retrieve the remote image. Retrieve the imgURL from the passed in array
NSData *imgData = [NSData dataWithContentsOfURL:[urlAndTagReference objectAtIndex:0]];
UIImage *img = [[UIImage alloc] initWithData:imgData];
// Create an array with the URL and imageView tag to
// reference the correct imageView in background thread.
NSMutableArray *arr = [[NSArray alloc] initWithObjects:img, [urlAndTagReference objectAtIndex:1], nil ];
// Image retrieved, call main thread method to update image, passing it the downloaded UIImage
[self performSelectorOnMainThread:#selector(assignImageToImageView:) withObject:arr waitUntilDone:YES];
}
- (void) assignImageToImageView:(NSArray *)imgAndTagReference
{
// Create a pool
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
// loop
for (UIImageView *checkView in [self.view subviews] ) {
NSLog(#"Checking tag: %d against passed in tag %d",[checkView tag], [[imgAndTagReference objectAtIndex:1] intValue]);
if ([checkView tag] == [[imgAndTagReference objectAtIndex:1] intValue]) {
// Found imageView from tag, update with img
[checkView setImage:[imgAndTagReference objectAtIndex:0]];
//set contentMode to scale aspect to fit
checkView.contentMode = UIViewContentModeScaleAspectFit;
//change width of frame
CGRect frame = checkView.frame;
frame.size.width = 80;
checkView.frame = frame;
}
}
// release the pool
[pool release];
// Remove the activity indicator created in ViewDidLoad()
//[self.activityIndicator removeFromSuperview];
}
-(void)buttonPressed:(id)sender
{
UIButton *imgButton = (UIButton *)sender;
int q=imgButton.tag;
string=[[NSString alloc] init];
string=[NSString stringWithString:[urlarry objectAtIndex:q]];
// NSLog(#"aap str is :%#",appDel.appstr);
// [self.navigationController pushViewController:objimv animated:YES];
}
i found an issue with Photo Library Images. It not displaying first time in my View,Image View is blank while loading first time.
Because i found Asset Library block working on another thread.After reloading my View ,I can see all the Images. However first time the Image Views are Blank.
can any one tell me a good way to deal with the problem
It working with Bundle Images.
also some times console shows that
app is crashing due to Program received signal: “0”. Data Formatters temporarily unavailable, will re-try after a 'continue'. (Unknown error loading shared library "/Developer/usr/lib/libXcodeDebuggerSupport.dylib")
My Code:
for (int j = 0; j<9; j++)
{
//allocating View
UIView *smallView = [[UIView alloc] initWithFrame:CGRectMake(xCordImage, yCordImage, 200, 190)];
// allocating ImageView
imageViewTopic = [[[UIImageView alloc] init] autorelease];
typedef void (^ALAssetsLibraryAssetForURLResultBlock)(ALAsset *asset);
typedef void (^ALAssetsLibraryAccessFailureBlock)(NSError *error);
ALAssetsLibraryAssetForURLResultBlock resultblock = ^(ALAsset *myasset)
{
ALAssetRepresentation *rep = [myasset defaultRepresentation];
CGImageRef iref = [rep fullResolutionImage];
UIImage *images;
if (iref) {
images = [UIImage imageWithCGImage:iref];
}
else {
images = [UIImage imageNamed:#"Nofile.png"];
}
imageViewTopic .image = images ;
};
ALAssetsLibraryAccessFailureBlock failureblock = ^(NSError *myerror)
{
imageViewTopic .image = [UIImage imageNamed:#"Nofile.png"];
NSLog(#"booya, cant get image - %#",[myerror localizedDescription]);
};
NSString *string ;
MyClass *obj = [imageFileNameArray objectAtIndex:j];
**//obj.fileName contains ALAsset URL of a Image**
string = obj.fileName;
NSURL *asseturl = [NSURL URLWithString:string];
ALAssetsLibrary* assetslibrary = [[[ALAssetsLibrary alloc] init] autorelease];
[assetslibrary assetForURL:asseturl resultBlock:resultblock
failureBlock:failureblock];
imageViewTopic.userInteractionEnabled = YES;
imageViewTopic.frame = CGRectMake(0,0, 200, 150);
[currentView addSubview:scroller];
**// adding the imageView to View**
[smallView addSubview:imageViewTopic];
[myView addSubview:smallView];
[scroller addSubview:myView];
}
I am using this method to show images in scroll view with lazy loading. It works well.
First initialize the value of j1. And data is the image data coming from loop from an array.
dispatch_async(dispatch_get_global_queue(0,0), ^{
NSData * data = [[NSData alloc] initWithContentsOfURL:url];
if ( data == nil )
return;
dispatch_async(dispatch_get_main_queue(), ^{
__block int j1=_j;
// WARNING: is the cell still using the same data by this point??
// NSURL *url = [NSURL URLWithString: imageName];
UIImage *image = [UIImage imageWithData: data]; //image.size.height
image1=[[UIImageView alloc] initWithFrame:CGRectMake(j1,10,image.size.width,image.size.height)];
image1.image=image;
CALayer *layer = [image1 layer];
[layer setMasksToBounds:YES];
[layer setCornerRadius:0.0]; //note that when radius is 0, the border is a rectangle
[layer setBorderWidth:3.0];
[layer setBorderColor:[[UIColor whiteColor] CGColor]];
[portfolio_scroll addSubview:image1];
});
});
_j = _j+ 320;