Turn a String value to a URL value - ios

Question

im redoing my ode after getting mixed up with some concepts of swift. Have in mind im new to swift.
In my project there are currently 2 ViewControllers, in the first one there is a UITextField and a UIButton. in the second one there is a UIWebView.
I know that the UIWebView only allows a URL type address, so i want the text introduced in the UITextField to be a URL, So how do i change the string introduced into a URL and display that value (URL introduced) in the UIWebView? Should i store that value in a global variable? I really tried all...

Answer 1

You can send it to the nextVC via Segue , or store it in defaults and read it there
let myUrl = URL(string:textfield.text)
self.performSegue(withIdentifier: "goToNext", sender:myUrl)
//
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if let let next = segue.destination as? nextVC {
next.currentUrl = sender as! URL
}
}
//
class nextVC : UIViewController
{
var currentUrl:URL?
}

Answer 2

It is very important to check if the user has entered a valid url. you can check that in Second viewController while loading the request from url.
Here is the overall code :
First viewController :
var url: String!
url = URL(string:textfield.text) // Convert text to url
self.performSegue(withIdentifier: "yourIdentifier", sender:url) // Go from one VC to other.
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if let let vc = segue.destination as? nextVC {
vc.url = self.url
}
}
Second viewController :
var url: String! // Global var
if url.isUrl
{
webView.loadRequest(URLRequest(url: url!))
}
else
{
print("invalid url")
}
Validate URL string extension :
extension String {
var isUrl: Bool {
// for http://regexr.com checking
// (?:(?:https?|ftp):\/\/)(?:xn--)?(?:\S+(?::\S*)?#)?(?:(?!10(?:\.\d{1,3}){3})(?!127(?:\.\d{1,3}){3})(?!169\.254(?:\.\d{1,3}){2})(?!192\.168(?:\.\d{1,3}){2})(?!172\.(?:1[6-9]|2\d|3[0-1])(?:\.\d{1,3}){2})(?:[1-9]\d?|1\d\d|2[01]\d|22[0-3])(?:\.(?:1?\d{1,2}|2[0-4]\d|25[0-5])){2}(?:\.(?:[1-9]\d?|1\d\d|2[0-4]\d|25[0-4]))|(?:(?:[a-z\u00a1-\uffff0-9]+-?)*[a-z\u00a1-\uffff0-9]+)(?:\.(?:[a-z\u00a1-\uffff0-9]+-?)*[a-z\u00a1-\uffff0-9]+)*(?:\.(?:[#-z\u00a1-\uffff]{2,})))(?::\d{2,5})?(?:\/[^\s]*)?
let schemes = URLSchemes.getAllSchemes(separetedBy: "|").replacingOccurrences(of: "://", with: "")
let regex = "(?:(?:\(schemes)):\\/\\/)(?:xn--)?(?:\\S+(?::\\S*)?#)?(?:(?!10(?:\\.\\d{1,3}){3})(?!127(?:\\.\\d{1,3}){3})(?!169\\.254(?:\\.\\d{1,3}){2})(?!192\\.168(?:\\.\\d{1,3}){2})(?!172\\.(?:1[6-9]|2\\d|3[0-1])(?:\\.\\d{1,3}){2})(?:[1-9]\\d?|1\\d\\d|2[01]\\d|22[0-3])(?:\\.(?:1?\\d{1,2}|2[0-4]\\d|25[0-5])){2}(?:\\.(?:[1-9]\\d?|1\\d\\d|2[0-4]\\d|25[0-4]))|(?:(?:[a-z\\u00a1-\\uffff0-9]+-?)*[a-z\\u00a1-\\uffff0-9]+)(?:\\.(?:[a-z\\u00a1-\\uffff0-9]+-?)*[a-z\\u00a1-\\uffff0-9]+)*(?:\\.(?:[#-z\\u00a1-\\uffff]{2,})))(?::\\d{2,5})?(?:\\/[^\\s]*)?"
let regularExpression = try! NSRegularExpression(pattern: regex, options: [])
let range = NSRange(location: 0, length: self.characters.count)
let matches = regularExpression.matches(in: self, options: [], range: range)
for match in matches {
if range.location == match.range.location && range.length == match.range.length {
return true
}
}
return false
}
var toURL: URL? {
let urlChecker: (String)->(URL?) = { url_string in
if url_string.isUrl, let url = URL(string: url_string) {
return url
}
return nil
}
if !contains(".") {
return nil
}
if let url = urlChecker(self) {
return url
}
let scheme = URLSchemes.detectScheme(urlString: self)
if scheme == .unknown {
let newEncodedString = URLSchemes.http.rawValue + self
if let url = urlChecker(newEncodedString) {
return url
}
}
return nil
}
}

Answer 3

Here is an example of how to do this.
Here is the gist:
ViewController:
class ViewController: UIViewController, UIWebViewDelegate {
#IBOutlet weak var urlTextView: UITextField!
override func viewDidLoad() {
super.viewDidLoad()
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if let webViewController = segue.destination as? WebViewController {
if let url = sender as? URL {
webViewController.urlToLoad = url
}
}
}
#IBAction func gotoURLButtonAction(_ sender: Any) {
let url = self.urlTextView.text ?? ""
if url.count > 0 {
if isProperHTTPUrl(str: url) {
self.performSegue(withIdentifier: "ViewControllerToWebViewController", sender: URL(string: url))
} else {
showError("not proper url format")
}
} else {
showError("must set url")
}
}
func isProperHTTPUrl(str:String) -> Bool {
let re = try! NSRegularExpression(pattern: "(?i)https?:\\/.*", options: [])
return re.numberOfMatches(in: str, options: .anchored, range: NSRange(location: 0, length: str.count)) > 0
}
}
WebViewController:
class WebViewController: UIViewController {
var urlToLoad:URL?
#IBOutlet weak var webView: UIWebView!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
if let url = self.urlToLoad {
self.webView.loadRequest(URLRequest(url: url))
}
}
public func webView(_ webView: UIWebView, didFailLoadWithError error: Error) {
showError("Unable to load, \(error)")
}
}