Unable to load images asynchronous with FSPagerView - ios

Question

I have problem displaying the images in the slider because I have to wait for them to download and then load them inside the FSPagerViewCell ImageView.
Inside the delegate function
- (FSPagerViewCell *)pagerView:(FSPagerView *)pagerView cellForItemAtIndex:(NSInteger)index
I am using an async function which when the image is ready, returns the downloaded image.
I use
dispatch_async(dispatch_get_main_queue(), ^{
to load the image inside the FSPagerViewCell.imageView
but it doesn't show anything, just white space.
Here is the complete code:
- (FSPagerViewCell *)pagerView:(FSPagerView *)pagerView cellForItemAtIndex:(NSInteger)index
{
FSPagerViewCell *cell = [pagerView dequeueReusableCellWithReuseIdentifier:#"pagerCell" atIndex:index];
if (index < [arrMediaGallery count])
{
pageControl.currentPage=index;
MediaGallery *firstImage = arrMediaGallery[index];
NSString *imageName = firstImage.Source;
NSString *imageURL;
if (imageName != nil && [imageName isEqualToString:#"NULL"] == NO && [imageName isEqualToString:#""] == NO) {
imageName = [NSString stringWithFormat:#"thumblarge_%#", imageName];
imageURL = [NSString stringWithFormat:#"%#/cache/photos/%#", [MyApp sharedInstance].settings.StaticURL, imageName];
}
UIImage *image = [NetworkUtilities resolveImageWithName:imageName];
if (image == nil) {
ProcessServerData *processData = [ProcessServerData new];
[processData downloadImageForURL:imageURL verifyDownload:NO
verifyHash:nil
oldImageName:nil
parentView:[cell contentView]
completion:^(NSError *error) {
UIImage* image = [NetworkUtilities resolveImageWithName:[NSString stringWithFormat:#"%#", imageName]];
dispatch_async(dispatch_get_main_queue(), ^{
[UIView transitionWithView:cell.imageView
duration:2.0f
options:UIViewAnimationOptionTransitionCrossDissolve
animations:^{
[cell.imageView setImage:image];
} completion:nil];
});
}];
}
else {
[cell.imageView setImage:image];
}
}
return cell;
}
Am I doing something wrong?

Answer 1

Step:1 - install From "https://github.com/WenchaoD/FSPagerView"
Step:2 - import "FSPagerViewDataSource,FSPagerViewDelegate" in VC
Step:3 - implement methods
//MARK: - FSPagerview Delegate and Datasource -
func numberOfItems(in pagerView: FSPagerView) -> Int
{
if pagerView == self.News_images_View
{
return 3
}
else
{
return 3
}
}
func pagerView(_ pagerView: FSPagerView, cellForItemAt index: Int) -> FSPagerViewCell
{
let cell = pagerView.dequeueReusableCell(withReuseIdentifier: "cell", at: index)
cell.imageView?.contentMode = .scaleAspectFit
cell.imageView?.clipsToBounds = true
if pagerView == self.News_images_View
{
cell.imageView?.image = UIImage(named: "noticia.jpg")
}
return cell
}
func pagerView(_ pagerView: FSPagerView, didSelectItemAt index: Int)
{
if pagerView == self.News_images_View
{
}
}
#IBOutlet var viewFirstAdvView: FSPagerView!
Inside ViewDidLoad
self.viewFirstAdvView.register(FSPagerViewCell.self, forCellWithReuseIdentifier: "cell") self.viewFirstAdvView.itemSize =
CGSize(width: self.view.frame.size.width, height:
UIScreen.main.bounds.size.width / 2)
self.viewFirstAdvView.isInfinite = true
self.viewFirstAdvView.automaticSlidingInterval = 3.0
self.lastAdvertiseView.transformer =
FSPagerViewTransformer(type:.crossFading)