UIImageView and UIImage. Load Image From Remote URL.

In this Swift code example we will learn how to create UIImageView programmatically and how to load an image from a remote url.

  • Create UIImageView and UIImage programmatically
  • Load image data from a remote url
  • Learn how to use dispatch_get_global_queue to start a background thread
  • Learn how to use dispatch_get_main_queue to update UI when background thread completes
  • Add UIImageView as subview to main view
  • Position UIImageView at the centre of UIView
  
    import UIKit
  
  class ViewController: UIViewController {
    override func viewDidLoad() {
        super.viewDidLoad()
    }
    
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        
        let imageUrlString = "http://swiftdeveloperblog.com/wp-content/uploads/2015/07/1.jpeg"
        let imageUrl:URL = URL(string: imageUrlString)!
        
        // Start background thread so that image loading does not make app unresponsive
         DispatchQueue.global(qos: .userInitiated).async {
            
            let imageData:NSData = NSData(contentsOf: imageUrl)!
            let imageView = UIImageView(frame: CGRect(x:0, y:0, width:200, height:200))
            imageView.center = self.view.center
            
            // When from background thread, UI needs to be updated on main_queue
           DispatchQueue.main.async {
                let image = UIImage(data: imageData as Data)
                imageView.image = image
                imageView.contentMode = UIViewContentMode.scaleAspectFit
                self.view.addSubview(imageView)      
            }
        }
    }
    
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
    
  }
 

Create an Image With Rounded Corners in Swift

Check out this code example that demonstrates how to create an Image with rounded corners.

Make UIImage Corners Rounded


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