Add OK button to alerts when AlertState's buttons array is empty (#302)

Author: acosmicflamingo

Sources/UIKitNavigation/Navigation/UIAlertController.swift

@@ -24,6 +24,9 @@
       for button in state.buttons {
         addAction(UIAlertAction(button, action: handler))
       }
+      if state.buttons.isEmpty {
+        addAction(UIAlertAction(title: "OK", style: .cancel))
+      }
     }
 
     /// Creates and returns a view controller for displaying an action sheet using a data
@@ -57,6 +60,9 @@
       for button in state.buttons {
         addAction(UIAlertAction(button, action: handler))
       }
+      if state.buttons.isEmpty {
+        addAction(UIAlertAction(title: "OK", style: .cancel))
+      }
     }
   }