How to create uialertcontroller in global swift

Question

I\'m trying to create uialertcontroller in Config.swift file as follow.

static func showAlertMessage(titleStr:String, messageStr:St         


        

Answer 1

If you want to present from AppDelegate windows you can use like this

UIApplication.sharedApplication().delegate?.window.rootViewController?.presentViewController(vc, animated: true, completion: nil)

Answer 2

Details

• Swift 5.1, Xcode 11.3.1

Global UIAlertController With UIViewController Extension

extension UIViewController{

    // Global Alert
    // Define Your number of buttons, styles and completion
    public func openAlert(title: String,
                          message: String,
                          alertStyle:UIAlertController.Style,
                          actionTitles:[String],
                          actionStyles:[UIAlertAction.Style],
                          actions: [((UIAlertAction) -> Void)]){

        let alertController = UIAlertController(title: title, message: message, preferredStyle: alertStyle)
        for(index, indexTitle) in actionTitles.enumerated(){
            let action = UIAlertAction(title: indexTitle, style: actionStyles[index], handler: actions[index])
            alertController.addAction(action)
        }
        self.present(alertController, animated: true)
    }
}

Usage

Alert

self.openAlert(title: "alert",
                      message: "add your message",
                      alertStyle: .alert,
                      actionTitles: ["Okay", "Cancel"],
                      actionStyles: [.default, .cancel],
                      actions: [
                          {_ in
                               print("okay click")
                          },
                          {_ in
                               print("cancel click")
                          }
                     ])

ActionSheet

self.openAlert(title: "actionsheet",
                  message: "add your message",
                  alertStyle: .actionSheet,
                  actionTitles: ["Okay", "Cancel"],
                  actionStyles: [.default, .cancel],
                  actions: [
                      {_ in
                           print("okay click")
                      },
                      {_ in
                           print("cancel click")
                      }
                 ])

Answer 3

self.window would mean that there's a window object in this class, and it's not the case.

You would need to use your let window : UIWindow? with window?.presentViewController(alert, animated: true, completion: nil), but this won't help, since this window does not actually represent any existing window, and it's not a view controller anyway.

So I suggest you pass the actual view controller you'll be using to the method:

static func showAlertMessage(vc: UIViewController, titleStr:String, messageStr:String) -> Void {
    let alert = UIAlertController(title: titleStr, message: messageStr, preferredStyle: UIAlertControllerStyle.Alert);
    vc.presentViewController(alert, animated: true, completion: nil)
}

and you call it from a class where a UIViewController object is available.

Answer 4

You can try this, please add below code in AppDelegate.swift file.

 static func showAlertView(vc : UIViewController, titleString : String , messageString: String) ->()
    {
        let alertView = UIAlertController(title: titleString, message: messageString, preferredStyle: .alert)

        let alertAction = UIAlertAction(title: "ok", style: .cancel) { (alert) in
            vc.dismiss(animated: true, completion: nil)
        }
        alertView.addAction(alertAction)
        vc.present(alertView, animated: true, completion: nil)

    }

and call showAlertView method from any viewcontroller

AppDelegate.showAlertView(vc: self, titleString: "testTitle", messageString: "test msg")

Answer 5

swift

Here's what I used, this is the same as @penatheboss answered, just add the ability of adding actions and handlers.

extension UIViewController {
    func popupAlert(title: String?, message: String?, actionTitles:[String?], actions:[((UIAlertAction) -> Void)?]) {
        let alert = UIAlertController(title: title, message: message, preferredStyle: .alert)
        for (index, title) in actionTitles.enumerated() {
            let action = UIAlertAction(title: title, style: .default, handler: actions[index])
            alert.addAction(action)
        }
        self.present(alert, animated: true, completion: nil)
    }
}

Just make sure actionTitles and actions array the same count. Pass nil if you don't need any action handler closure.

self.popupAlert(title: "Title", message: " Oops, xxxx ", actionTitles: ["Option1","Option2","Option3"], actions:[{action1 in

},{action2 in

}, nil])

Objective C:

Add the category for UIViewController

UIViewController+PopAlert.h

#import <UIKit/UIKit.h>

@interface UIViewController (UIViewControllerCategory)
- (void) popAlertWithTitle: (NSString*) title message: (NSString*) message actionTitles:(NSArray *) actionTitles actions:(NSArray*)actions;
@end

UIViewController+PopAlert.m

#import "UIViewController+PopAlert.h"

@implementation UIViewController (UIViewControllerCategory)
- (void) popAlertWithTitle: (NSString*) title message: (NSString*) message actionTitles:(NSArray *) actionTitles actions:(NSArray*)actions {
    UIAlertController *alert = [UIAlertController alertControllerWithTitle:title message:message preferredStyle:UIAlertControllerStyleAlert];
    [actionTitles enumerateObjectsUsingBlock:^(id  _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
        UIAlertAction *action = [UIAlertAction actionWithTitle:obj style:UIAlertActionStyleDefault handler:actions[idx]];
        [alert addAction:action];
    }];
    [self presentViewController:alert animated:YES completion:nil];
}
@end

Usage:

#import UIViewController+PopAlert.h

...

[super viewDidDisappear:animated];
    NSArray *actions = @[^(){NSLog(@"I am action1");}, ^(){NSLog(@"I am action2");}];
    [self popAlertWithTitle:@"I am title" message:@"good" actionTitles:@[@"good1", @"good2"] actions:actions];

Answer 6

I created a alerMessage class .I can call any where in my application

//Common Alert Message Class 

class AlertMessage {

internal static var alertMessageController:UIAlertController!

internal static func disPlayAlertMessage(titleMessage:String, alertMsg:String){


    AlertMessage.alertMessageController = UIAlertController(title: titleMessage, message:
        alertMsg, preferredStyle: UIAlertControllerStyle.Alert)

    AlertMessage.alertMessageController.addAction(UIAlertAction(title: "Ok", style: UIAlertActionStyle.Default,handler: nil))
    if let controller = UIApplication.sharedApplication().keyWindow?.rootViewController?.presentedViewController {
        controller.presentViewController(AlertMessage.alertMessageController, animated: true, completion: nil)
    }
    else{
        UIApplication.sharedApplication().delegate?.window!!.rootViewController?.presentViewController(AlertMessage.alertMessageController, animated: true, completion: nil)
    }

    return

 }
}