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ios - UIControlEventEditingChanged doesn't get fired when using setText of UITextfield

I am currently trying to track the states of a textfield.

I am using a custom datePicker which sets the text via -setText

[self.textField setText:[self.dateFormatter stringFromDate:self.date]];

Inside my textFieldDelegate I wrote the following code:

-(void)viewDidLoad {
  [super viewDidLoad];
  self.travelToOnTextField.delegate = self;
  [self.travelToOnTextField addTarget:self action:@selector(travelToOnTextFieldDidChange:) forControlEvents:UIControlEventEditingChanged];
}

-(void)travelToOnTextFieldDidChange:(id)sender
{
   NSLog(@"Event Handler called");
}

If I change the text through my custom Datepicker the Method travelToOnDateTextFieldDidChange doesn't get called. But if I change the text using my Computer Keyboard it gets called for some reason.

Is this intentional?

See Question&Answers more detail:os

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1 Answer

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by (71.8m points)

I had to rate this question up because this is super important.

It appears this has changed in iOS6. Maybe even iOS5. This event USED to be the preferred method for observing text changes in a UITextField. I've been using it since iOS3. After recompiling my app on iOS6 to perform some updates, it mysteriously stopped working. Parts of my app use:

[UITextField insertText];

and others use

[UITextField setText];

or

UITextField.text = @"xxx";

For whatever reason it's important to note that setText events no longer fire the Editing Changed event. If you use an insertText method, it still works.

So if you're in a bind and you just need a quick fix, you can change out your code from:

textField.text;

or

[textField setText:@"xxx"];

to

textField.text = @"";
[textField insertText:@"new text"];

This also works:

[((UITextField*)view) sendActionsForControlEvents:UIControlEventEditingChanged];

I hope this helps someone, because I wasted an entire day trying to figure out why this code suddenly stopped working when I moved up to iOS6.

You can still use NSNotificationCenter as well. See the UITextField reference for more info:

https://developer.apple.com/documentation/uikit/uitextfield


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