fix bug on URL loginweb

iOSClient/Login/NCLoginWeb.swift

@@ -64,7 +64,11 @@ class NCLoginWeb: UIViewController {
         activityIndicator.startAnimating()
         self.view.addSubview(activityIndicator)
         
-        loadWebPage(webView: webView!, url: URL(string: urlBase)!)
+        if let url = URL(string: urlBase) {
+            loadWebPage(webView: webView!, url: url)
+        } else {
+            NCContentPresenter.shared.messageNotification("_error_", description: "_login_url_error_", delay: TimeInterval(k_dismissAfterSecond), type: NCContentPresenter.messageType.error, errorCode: 0)
+        }
     }
     
     override func viewDidAppear(_ animated: Bool) {

iOSClient/Media/NCMedia.swift

@@ -621,7 +621,7 @@ extension NCMedia {
                 
             }  else {
                 
-                 NCContentPresenter.shared.messageNotification("_error_", description: message, delay: TimeInterval(k_dismissAfterSecond), type: NCContentPresenter.messageType.error, errorCode: errorCode)
+                NCContentPresenter.shared.messageNotification("_error_", description: message, delay: TimeInterval(k_dismissAfterSecond), type: NCContentPresenter.messageType.error, errorCode: errorCode)
                 
                 self.loadingSearch = false
                 

iOSClient/Supporting Files/en.lproj/Localizable.strings

@@ -284,6 +284,7 @@
 "_account_already_exists_"      = "The account %@ already exists";
 "_traditional_login_"           = "Revert to old login method";
 "_web_login_"                   = "Revert to web login method";
+"_login_url_error_"             = "Url error, please verify your server url";
 
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