I have an app with a TextField. If TextField is empty then it is displayed UIAlertView with one button. When a user taps on a button in UIAlertView, he must return to the TextField.
I'm using self.TextField.becomeFirstResponder() for this. It works. But the problem is that the keyboard is displayed really slowly. It looks like there is a one second delay before displayed.
if TextField.text?.isEmpty ?? true {
let alert = UIAlertController(title: "Title", message: "Text", preferredStyle: .alert)
alert.addAction(UIAlertAction(title: "Okay", style: .cancel, handler: { (action: UIAlertAction!) in
self.TextField.becomeFirstResponder()
}))
self.present(alert, animated: true)
print("textField is empty")
} else { ...
Make sure that the Slow Animation is disabled in Debug menu:
Related
I want the user to press a button, and then for them to be able to see an alert where they can enter an input (to set a price for a service). The other logic involves saving data to a database, which is not really relevant to my problem.
I am using the following example:
https://stackoverflow.com/a/30139623/2411290
It definitely works, in that it shows the alert correctly, but once I include
print("Amount: \(self.tField.text)")
"self.tField.text" is not recognized. The specific error I get is:
value of type 'testVC' has no member 'tField'
#IBAction func setAmount(_ sender: Any) {
var tField: UITextField!
func configurationTextField(textField: UITextField!)
{
print("generating textField")
textField.placeholder = "Enter amount"
tField = textField
}
func handleCancel(alertView: UIAlertAction!)
{
print("Cancelled")
}
let alert = UIAlertController(title: "Set price of service", message: "", preferredStyle: .alert)
alert.addTextField(configurationHandler: configurationTextField)
alert.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler:handleCancel))
alert.addAction(UIAlertAction(title: "Done", style: .default, handler:{ (UIAlertAction) in
print("Done !!")
}))
self.present(alert, animated: true, completion: {
print("completion block")
print("Amount: \(self.tField.text)") // Error here
})
//// other logic for app
}
tField is a local variable inside your setAmount function. It is not a property of the class.
Change:
self.tField.text
to:
tField.text
That will allow you to access the local variable.
But the real question is why are you creating a local variable of UITextField inside this function? Why are you printing its text when the text field isn't used anywhere?
Most likely you should be accessing the alert's text field inside the action handler for the "Done" button. There's no need to do anything inside the completion block of presenting the alert.
#IBAction func setAmount(_ sender: Any) {
let alert = UIAlertController(title: "Set price of service", message: "", preferredStyle: .alert)
alert.addTextField(configurationHandler: { (textField) in
print("generating textField")
textField.placeholder = "Enter amount"
})
alert.addAction(UIAlertAction(title: "Cancel", style: .cancel) { (action) in
print("Cancelled")
})
alert.addAction(UIAlertAction(title: "Done", style: .default) { (action) in
print("Done !!")
if let textField = alert.textFields?.first {
print("Amount: \(textField.text)")
}
})
self.present(alert, animated: true, completion: nil)
}
My guess is that when you present an alert your current ViewController is the alert viewController... And in your alert there is no variable tField.
On the exampled you quoted the alert was presented only after the print with tField's value. That why that worked there and doesn't work in your case.
I have a signup screen with a phone number field.
If the user type a too short phone number, I display an UIAlertController.
After she dismisses the Alert, the user can't send her phone number again as the send button is tapped.
Is there a way to reload the view when the alert is dismissed to make the button untapped?
Thanks
func present_alert(title:String, content : String){
let myAlert = UIAlertController(title:title, message:content, preferredStyle:UIAlertControllerStyle.alert)
let okAction = UIAlertAction(title: "Ok", style: UIAlertActionStyle.default, handler:nil)
myAlert.addAction(okAction)
self.present(myAlert, animated:true)
}
the main reason on button click you disabled the yourbutton sender.isEnabled = false, when ever the alert is presented again enable your button , surely works addyourbuttonName.isEnabled = true
if you want to clear the current textfield value then use yourtextfield.text = ""
let alertController = UIAlertController(title: “Simple”, message: “Simple alertView demo with Cancel and Ok.”, preferredStyle: UIAlertControllerStyle.alert)
let okAction = UIAlertAction(title: “OK”, style: UIAlertActionStyle.default) { (result : UIAlertAction) -> Void in
print(“OK”)
yourtextfield.text = ""
yourtextfield.becomeFirstResponder()
addyourbuttonName.isEnabled = true
}
alertController.addAction(okAction)
self.present(alertController, animated: true, completion: nil)
func present_alert(title:String, content:String, button:UIButton){
let myAlert = UIAlertController(title:title, message:content, preferredStyle:UIAlertControllerStyle.alert)
let okAction = UIAlertAction(title: "Ok", style: UIAlertActionStyle.default, handler:nil)
myAlert.addAction(okAction)
self.present(myAlert, animated:true){
button.isEnabled = true
}
}
As i understand your issue the problem is that you receive your button false value of parameter "isEnabled". To fix that just add to your block last string:
buttonName.isEnabled = true
After click on UIAlertAction(cancel or ok), you can add some functionality in that ok or cancel method. In the final step of that method, add viewWillAppear(true) method. Then UIViewController automatically refresh.
I have written code for an alert to appear when the input in one of my UITextFields is less than 1050. It successfully appears when the inputs satisfies that, but after I press "OK" it instantly re-appears.
Below is the code in the viewDidLoad function:
override func viewDidLoad(){
super.viewDidLoad()
alert = UIAlertController(title: "Error", message: "Please enter an exit width value greater than 1050", preferredStyle: UIAlertControllerStyle.Alert)
let okay = UIAlertAction(title: "OK", style: UIAlertActionStyle.Destructive, handler: valueCalc)
alert.addAction(okay)
}
Then I have in my valueCalc function (which is called when a button is tapped):
#IBAction func valueCalc(sender: AnyObject){
if(Int(mmText.text!)! < 1050){ //mmText is an UITextField
self.presentViewController(alert, animated: true, completion: nil)
}
}
According to your line of code
let okay = UIAlertAction(title: "OK", style: UIAlertActionStyle.Destructive, handler: valueCalc)
Your handler name valueCalc is called when you press OK.
Again the value is calculated which when come out be less then the specified characters shows back you the alert.
Instead of that, replace this line in your code -
let okay = UIAlertAction(title: "OK", style: UIAlertActionStyle.Destructive, handler: handlerMethod)
and add this method to your code
func handlerMethod() {
//handle your action here after ok is pressed for e.g if you wanna just dismiss the alert then write
dismissViewControllerAnimated(true, completion: nil)
}
You have the handler argument for your UIAlertAction set to valueCalc. Therefore, whenever the user taps "OK", the method valueCalc gets run again, and since the value is (presumably) still the same, the alert is presented right back again.
Try this
override func viewDidLoad(){
super.viewDidLoad()
alert = UIAlertController(title: "Error", message: "Please enter an exit width value greater than 1050", preferredStyle: UIAlertControllerStyle.Alert)
let okay = UIAlertAction(
title: "OK",
style: UIAlertActionStyle.Destructive) { (action) in }
}
#IBAction func valueCalc(sender: AnyObject){
if(Int(mmText.text!)! < 1050){ //mmText is an UITextField
self.presentViewController(alert, animated: true, completion: nil)
}
I want to make a "rate app" alert, but for some reason it gets deallocated before showing it.
Here's the code:
func showAlert() {
if #available(iOS 8.0, *)
{
let alertController = UIAlertController(title: "Rate App", message: "Rate this app now", preferredStyle: .Alert)
let neverAction = UIAlertAction(title: "Never Show This Again", style: .Destructive, handler: { (action: UIAlertAction) in
self.userDefaults.setBool(true, forKey: "rateAlertRejected")
})
let rateAction = UIAlertAction(title: "Rate Now", style: .Default, handler: { (action: UIAlertAction) in
// Rate App
})
let remindAction = UIAlertAction(title: "Remind Me Later", style: .Cancel, handler: nil)
alertController.addAction(rateAction)
alertController.addAction(neverAction)
alertController.addAction(remindAction)
presentViewController(alertController, animated: true, completion: nil)
}
else
{
// Identical code (using UIAlertView) for iOS 7 which works perfectly
}
}
The method executes (in certain conditions, but for testing purposes it does it every time) after a custom unwind segue.
Why do I have this problem? I used UIAlertController before but I had no issues.
According to your comment you show showAlert in
a method that executes after a custom unwind segue.
unwind segue dismisses the view heriarchy and therefore your alert
does not get reference to a view controller to show from.
To solve this, show your alert in the View controller you unwind to or wait for the alert controller action to be completed before unwinding.
I wrote the following function below to display alerts through my project. Every time i check for an error in a form i display the alert when the user clicks submit. I want to simply show the alert, but not unwind the pervious segue. I want to stay at the current screen and give the user the opportunity to complete the form. Right now when the user clicks submit, it displays the alert ..but when i click the ok button to dismiss the alert it immediately unwinds the segue to the previous screen.
I have included the UIAlertViewDelegate in the class.... any ideas why this might be happening?
func displayAlert(title:String, error:String) {
var alert = UIAlertController(title: title, message: error, preferredStyle: UIAlertControllerStyle.Alert)
alert.addAction(UIAlertAction(title: "OK", style: .Default, handler: { action in
self.dismissViewControllerAnimated(true, completion: nil)
}))
self.presentViewController(alert, animated: true, completion: nil)
}
Never mind.
func displayAlert(title:String, error:String) {
var alert = UIAlertController(title: title, message: error, preferredStyle: UIAlertControllerStyle.Alert)
alert.addAction(UIAlertAction(title: "OK", style: .Default, handler: { action in
//comment out this line and it will still work. It will not segue back to the previous screen.
//self.dismissViewControllerAnimated(true, completion: nil)
}))
self.presentViewController(alert, animated: true, completion: nil)
}