Strange UIImageview remote image loading behaviour - iphone

Question

I am trying to load remote image on my imageview using the following code. displayImage is referenced with imageview at testview.xib
- (void)viewDidLoad
{
[super viewDidLoad];
self.displayImage.userInteractionEnabled = YES;
NSMutableURLRequest *requestWithBodyParams = [NSMutableURLRequest requestWithURL:self.gImg.URL];
NSData *imageData = [NSURLConnection sendSynchronousRequest:requestWithBodyParams returningResponse:nil error:nil];
self.originalImage = [UIImage imageWithData:imageData];
self.displayImage.contentMode = UIViewContentModeScaleAspectFit;
self.displayImage = [[UIImageView alloc] initWithImage:self.originalImage];
[self.displayImage setImage:self.originalImage];
NSLog(#"DisplayImage Object:%#",self.displayImage);
NSLog(#"height of Displayimage image:%.f",self.displayImage.image.size.height);
}
But the image is not showing. I am certain image did loaded on imageview. Here is output log:
DisplayImage Object:<UIImageView: 0x11033270; frame = (0 0; 720 632); opaque = NO; userInteractionEnabled = NO; layer = <CALayer: 0x1104c620>>
height of Displayimage image:632

Answer 1

Here I am modified your code:
No need to alloc the UIImageView in code, if you have the UIImageView in .xib.
NSURL *gImg = [NSURL URLWithString:#"http://www.vinfotech.com/sites/default/files/iphoe-app-design-ios7-way-12.jpg"];
NSMutableURLRequest *requestWithBodyParams = [NSMutableURLRequest requestWithURL:gImg];
NSData *imageData = [NSURLConnection sendSynchronousRequest:requestWithBodyParams returningResponse:nil error:nil];
UIImage *originalImage = [UIImage imageWithData:imageData];
self.displayImage.contentMode = UIViewContentModeScaleAspectFit;
// self.displayImage = [[UIImageView alloc] initWithImage:originalImage];
[self.displayImage setImage:originalImage];
NSLog(#"DisplayImage Object:%#",self.displayImage);
NSLog(#"height of Displayimage image:%.f",self.displayImage.image.size.height);
Hope so, this code helps you.

Answer 2

Create a dispatch queue:
dispatch_queue_t backgroundQueue = dispatch_queue_create("com.mayapp", NULL);
Use NSData method dataWithContentsOfURL and download the image in a background thread:
dispatch_async(backgroundQueue, ^(void) {
NSData *data = [NSData dataWithContentsOfURL:requestWithBodyParams];
//as soon as the image is downloaded, draw image in a main thread
dispatch_sync(dispatch_get_main_queue(), ^(void) {
self.originalImage = [UIImage imageWithData:data];
self.displayImage.contentMode = UIViewContentModeScaleAspectFit;
self.displayImage = [[UIImageView alloc] initWithImage:self.originalImage];
[self.displayImage setImage:self.originalImage];
});//close main block
});//background block

Answer 3

This Sample code works fine for me :
- (void)viewDidLoad
{
[super viewDidLoad];
NSURL *url = [NSURL URLWithString:#"http://iceclearmedia.com/wp-content/uploads/2011/04/SEO-and-url-Shorteners.jpg"];
NSData* imageData = [[NSData alloc] initWithContentsOfURL:url];
UIImage* image = [[UIImage alloc] initWithData:imageData] ;
[self performSelectorOnMainThread:#selector(displayImage:) withObject:image waitUntilDone:NO];
}
- (void)displayImage:(UIImage *)image {
[self.imagedownload setImage:image]; //UIImageView
}