Rxswift: UITextView.rx_text doesn't catch iOS autocorrect text changes

[timojaask]

UITextView.rx_text observes text changes via textViewDidChange. Unfortunately, when text changes due to iOS autocorrect, the textViewDidChange is not called, therefore rx_text never receives that new text.

You can test it by creating a text view, make sure autocorrection is enabled, observe rx_text, type a misspelled word and move focus away from the text view. The text will be automatically corrected, but the last change will never be observed via rx_text, because textViewDidChange doesn't fire when autocorrect happens.

[kzaher]

Hi @timojaask ,

I've confirmed the problem. This is the only way I know how to solve this, but I don't like it.

https://github.com/ReactiveX/RxSwift/commit/e14ca2e94d4e995c552c2d7c417f52ad9c3b75d7

Any ideas how to solve this more elegantly?

[sergdort]

Hi, guys
@kzaher how about rx_observeWeakly of text keypath

[kzaher]

Hi @sergdort ,

that's an interesting idea :) I've just tried it, and unfortunately it doesn't seem to work either :/

Also NSNotificationCenter.defaultCenter().rx_notification(UITextViewTextDidChangeNotification, object:self) doesn't fire in that case.

Is there some obvious API I'm missing?

[sergdort]

Just looked at how ReactiveCocoa did this, looks like they did the same and probable they also have bug =)

[kzaher]

Haha, yeah, I've also checked other reactive/binding frameworks :)

This hack is the best thing I could conjure so far. ¯_(ツ)_/¯
This does look like a bug in UITextView, but this is a pretty ugly one and would like to find some workaround.

[sergdort]

How about observe textViewDidEndEditing instead of func textView(textView: UITextView, shouldChangeTextInRange range: NSRange, replacementText text: String) -> Bool

Looks like this bug appears only when you moving focus away from the text view

[kzaher]

Yeah, that also appears to be working ...

I'm wondering is there any other edge case like this one what textViewDidEndEditing: can't catch ...

Maybe we can use textViewDidEndEditing: and I can just implement @objc public func textView(textView: UITextView, shouldChangeTextInRange range: NSRange, replacementText text: String) -> Bool { return true } so that if we need this uglier hack in future, we don't touch public interface ...

[sergdort]

Looks like this bug could also appears on UITextField rx_text

[sergdort]

There is also NSTextStorageDelegate in textStorage of UITextView
and probably method:

- (void)textStorage:(NSTextStorage *)textStorage didProcessEditing(NSTextStorageEditActions)editedMask range:(NSRange)editedRange changeInLength:(NSInteger)delta

could work too

[kzaher]

I have noticed that same behavior on UITextField also. I've also been able to repro this without ending editing :(

I think it's worth a shot to try

- (void)textStorage:(NSTextStorage *)textStorage didProcessEditing(NSTextStorageEditActions)editedMask range:(NSRange)editedRange changeInLength:(NSInteger)delta

... for NSTextView.

I'm still unsure how to solve NSTextField without equivalent ugly hack :/

[sergdort]

Hi @kzaher
Have you tried to add proxy target for UIControlEvents UIControlEvents.AllEditingEvents ?

With this setup
self.textField.addTarget(self, action: "textFieldDidChange:", forControlEvents: .AllEditingEvents)

I was able to get all changes of text

[sergdort]

Hi @kzaher looks like NSTextStorageDelegate works great, please take a look, may be I did something wrong :)

[kzaher]

This is done :)