Unable to start Activity Indicator in Swift 3? - ios

Question

I am new to IOS. I am trying to implement activity indicator while loading web view, but I am unable to do that.While debugging I encounter that animator is starting but it is not getting visible. I am using swift 3. Here my code is as below.Please let me know what I am doing wrong. If anyone have good resource to learn about activity indicator please mention that also.
class ViewController: UIViewController,UIWebViewDelegate {
var WebView: UIWebView!
override func viewDidLoad()
{
super.viewDidLoad()
WebView = UIWebView(frame: UIScreen.main.bounds)
WebView.delegate = self
view.addSubview(WebView)
if let url = URL(string: "https://apple.com")
{
let request = URLRequest(url: url)
WebView.loadRequest(request)
}
activityindicator.startAnimating()
activityindicator.color = UIColor.black
activityindicator.alpha = 1
activityindicator.isHidden = false
}
// weak var activityindicator: UIActivityIndicatorView!
let activityindicator = UIActivityIndicatorView()
func webViewDidStartLoad(_ webView: UIWebView)
{
activityindicator.startAnimating()
activityindicator.color = UIColor.black
activityindicator.alpha = 1
activityindicator.isHidden = false
UIApplication.shared.isNetworkActivityIndicatorVisible = true
}
func webViewDidFinishLoad(_ webView: UIWebView)
{
UIApplication.shared.isNetworkActivityIndicatorVisible = false
activityindicator.stopAnimating()
activityindicator.alpha = 0
activityindicator.isHidden = true
}
func webView(webView: UIWebView, didFailLoadWithError error: NSError)
{
activityindicator.isHidden = true
}
}

Answer 1

Looks like the activity indicator is not added to view. Similar to how we are adding webview, center and add the indicator in viewDidLoad (code below).
activityindicator.center = self.view.center
view.addSubview(activityindicator)
Also I would suggest moving the global declarations to one place. i.e move the indicator declaration let activityindicator = UIActivityIndicatorView(), to be below webview's on top, instead of middle of class. This helps in quick readability.

Answer 2

Here is your full code. Now it's working -
import UIKit
class ViewController: UIViewController,UIWebViewDelegate {
var WebView: UIWebView!
override func viewDidLoad()
{
super.viewDidLoad()
WebView = UIWebView(frame: UIScreen.main.bounds)
WebView.delegate = self
view.addSubview(WebView)
if let url = URL(string: "https://apple.com")
{
let request = URLRequest(url: url)
WebView.loadRequest(request)
}
activityindicator.startAnimating()
activityindicator.center = self.view.center
view.addSubview(activityindicator)
activityindicator.color = UIColor.black
activityindicator.alpha = 1
}
// weak var activityindicator: UIActivityIndicatorView!
let activityindicator = UIActivityIndicatorView()
func webViewDidStartLoad(_ webView: UIWebView)
{
activityindicator.startAnimating()
activityindicator.color = UIColor.black
activityindicator.alpha = 1
activityindicator.isHidden = false
UIApplication.shared.isNetworkActivityIndicatorVisible = true
}
func webViewDidFinishLoad(_ webView: UIWebView)
{
UIApplication.shared.isNetworkActivityIndicatorVisible = false
activityindicator.stopAnimating()
activityindicator.alpha = 0
activityindicator.isHidden = true
}
func webView(webView: UIWebView, didFailLoadWithError error: NSError)
{
activityindicator.isHidden = true
}
}