I'm presenting a UIAlertView
to the user and I can't figure out how to write the handler. This is my attempt:
let alert = UIAlertController(title: "Title",
message: "Message",
preferredStyle: UIAlertControllerStyle.Alert)
alert.addAction(UIAlertAction(title: "Okay",
style: UIAlertActionStyle.Default,
handler: {self in println("Foo")})
I get a bunch of issues in Xcode.
The documentation says convenience init(title title: String!, style style: UIAlertActionStyle, handler handler: ((UIAlertAction!) -> Void)!)
The whole blocks/closures is a little over my head at the moment. Any suggestion are much appreciated.
This question is related to
ios
uialertview
swift
uialertcontroller
In Swift
let alertController = UIAlertController(title:"Title", message: "Message", preferredStyle:.alert)
let Action = UIAlertAction.init(title: "Ok", style: .default) { (UIAlertAction) in
// Write Your code Here
}
alertController.addAction(Action)
self.present(alertController, animated: true, completion: nil)
In Objective C
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"Title" message:@"Message" preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *OK = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action)
{
}];
[alertController addAction:OK];
[self presentViewController:alertController animated:YES completion:nil];
create alert, tested in xcode 9
let alert = UIAlertController(title: "title", message: "message", preferredStyle: UIAlertControllerStyle.alert)
alert.addAction(UIAlertAction(title: "Ok", style: UIAlertActionStyle.default, handler: self.finishAlert))
self.present(alert, animated: true, completion: nil)
and the function
func finishAlert(alert: UIAlertAction!)
{
}
In Swift 4 :
let alert=UIAlertController(title:"someAlert", message: "someMessage", preferredStyle:UIAlertControllerStyle.alert )
alert.addAction(UIAlertAction(title: "ok", style: UIAlertActionStyle.default, handler: {
_ in print("FOO ")
}))
present(alert, animated: true, completion: nil)
Functions are first-class objects in Swift. So if you don't want to use a closure, you can also just define a function with the appropriate signature and then pass it as the handler
argument. Observe:
func someHandler(alert: UIAlertAction!) {
// Do something...
}
alert.addAction(UIAlertAction(title: "Okay",
style: UIAlertActionStyle.Default,
handler: someHandler))
Syntax change in swift 3.0
alert.addAction(UIAlertAction(title: "Okay",
style: .default,
handler: { _ in print("Foo") } ))
Lets assume that you want an UIAlertAction with main title, two actions (save and discard) and cancel button:
let actionSheetController = UIAlertController (title: "My Action Title", message: "", preferredStyle: UIAlertControllerStyle.ActionSheet)
//Add Cancel-Action
actionSheetController.addAction(UIAlertAction(title: "Cancel", style: UIAlertActionStyle.Cancel, handler: nil))
//Add Save-Action
actionSheetController.addAction(UIAlertAction(title: "Save", style: UIAlertActionStyle.Default, handler: { (actionSheetController) -> Void in
print("handle Save action...")
}))
//Add Discard-Action
actionSheetController.addAction(UIAlertAction(title: "Discard", style: UIAlertActionStyle.Default, handler: { (actionSheetController) -> Void in
print("handle Discard action ...")
}))
//present actionSheetController
presentViewController(actionSheetController, animated: true, completion: nil)
This works for swift 2 (Xcode Version 7.0 beta 3)
You can do it as simple as this using swift 2:
let alertController = UIAlertController(title: "iOScreator", message:
"Hello, world!", preferredStyle: UIAlertControllerStyle.Alert)
alertController.addAction(UIAlertAction(title: "Dismiss", style: UIAlertActionStyle.Destructive,handler: { action in
self.pressed()
}))
func pressed()
{
print("you pressed")
}
**or**
let alertController = UIAlertController(title: "iOScreator", message:
"Hello, world!", preferredStyle: UIAlertControllerStyle.Alert)
alertController.addAction(UIAlertAction(title: "Dismiss", style: UIAlertActionStyle.Destructive,handler: { action in
print("pressed")
}))
All the answers above are correct i am just showing another way that can be done.
this is how i do it with xcode 7.3.1
// create function
func sayhi(){
print("hello")
}
// create the button
let sayinghi = UIAlertAction(title: "More", style: UIAlertActionStyle.Default, handler: { action in
self.sayhi()})
// adding the button to the alert control
myAlert.addAction(sayhi);
// the whole code, this code will add 2 buttons
@IBAction func sayhi(sender: AnyObject) {
let myAlert = UIAlertController(title: "Alert", message:"sup", preferredStyle: UIAlertControllerStyle.Alert);
let okAction = UIAlertAction(title: "OK", style: UIAlertActionStyle.Default, handler:nil)
let sayhi = UIAlertAction(title: "say hi", style: UIAlertActionStyle.Default, handler: { action in
self.sayhi()})
// this action can add to more button
myAlert.addAction(okAction);
myAlert.addAction(sayhi);
self.presentViewController(myAlert, animated: true, completion: nil)
}
func sayhi(){
// move to tabbarcontroller
print("hello")
}
Source: Stackoverflow.com