The specified URL has an unsupported scheme. Only HTTP and HTTPS URLs are supported

Question

My code is

let idx = (self.tappedIndexPath?.row)!
let pcs = self.sortedArray[idx]
let urlW = URL(string: ("https://en.wikipedia.org/w/index.php?search=\(String(describing: pcs.name))".addingPercentEncoding(withAllowedCharacters: .urlHostAllowed))!)
let svm = SFSafariViewController.init(url: urlW!)
self.navigationController?.pushViewController(svm, animated: true)

is crashing for this error:

"The specified URL has an unsupported scheme. Only HTTP and HTTPS URLs are supported."

I do not understand the problem, my url is in https so why it is crashing?

Answer 1

The error message is misleading. Too many percent escaped characters confuse the URL(string initializer.

The solution is to percent escape only the search query using the proper character set ( urlHostAllowed is only for the host, the part between :// and the following slash) and for safety add optional bindings:

let pcs = self.sortedArray[idx]
if let query = pcs.name.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed),
    let urlW = URL(string: "https://en.wikipedia.org/w/index.php?search=" + query) {
       let svm = SFSafariViewController(url: urlW)
       self.navigationController?.pushViewController(svm, animated: true)
} else {
    print("Bad URL")
}