KEEP keyboard ON when UIAlertcontroller is presented in Swift?

问题

When the alert pops up the keyboard is dismissed. I have looked everywhere but did not find solutions to keep the keyboard visible. When alert is presented the textfield seems to resign first responder automatically as the alert is presented modally. How is it possible to keep the keyboard behind this alert which means the textfield still editing even if no interaction will be possible ?

回答1:

This solution works for me:

let rootViewController: UIViewController = 
    UIApplication.sharedApplication().windows.lastObject.rootViewController!!
rootViewController.presentViewController(alert, animated: true, completion: nil)

edit by @galambalazs: The reason it works is because:

You can grab the window with the current highest window level and present your View Controller inside that Window (making it the top View Controller in the top Window).

UIApplication.sharedApplication().windows
The windows in the array are ordered from back to front by window level;
thus, the last window in the array is on top of all other app windows.

Also you might want to set the tintColor of that window so that it matches your apps global tintColor.

UIWindow *topWindow = [UIApplication sharedApplication].windows.lastObject;
// we inherit the main window's tintColor because topWindow may not have the same
topWindow.tintColor = [UIApplication sharedApplication].delegate.window.tintColor;

回答2:

For Swift 3 and iOS11

if let alertWindow = UIApplication.shared.windows.last, alertWindow.windowLevel == 10000001.0 // If keyboard is open
  { // Make sure keyboard is open
    alertWindow.rootViewController?.present(alertController, animated: true, completion: nil)
  }
  else
  {
    viewController?.present(alertController, animated: true, completion: nil)
  }

来源：https://stackoverflow.com/questions/28564710/keep-keyboard-on-when-uialertcontroller-is-presented-in-swift

标签

ios

swift

keyboard

uialertcontroller

presentviewcontroller