UITextField does not update caret when toggling isSecureText

Originator:macbellingrath
Number:rdar://38465011 Date Originated:03/14/2018
Status:Open Resolved:
Product:UIKit Product Version:11.2.0
Classification:Bug Reproducible:Always
 
Area:
UIKit

Summary:
If a UITextField contains secure text, toggling `isSecureText` does not update the position of the caret. In our case, this makes it appear as if the field has appended a single white space to the text in the field.

Steps to Reproduce:
- Initialize a UITextField
- Set `isSecureText` to true on the text field
- Enter some text in the field 
- Programmatically toggle `isSecureText` to reveal the masked characters

Expected Results:
When the characters are revealed, there the caret moves to the end of the unmasked characters

Actual Results:
The caret remains in the same position without adjusting for the changed characters. 

Version/Build:
iOS 11.2.0

Configuration:
Xcode 9.2
iPhone X, iOS 11.2.0

Comments

Workaround

Seems update is delayed and rendering is wrong.

In tick, caretRect(for: endOfDocument) becomes correct, but not in immediately after toggling isSecureTextEntry. Rendering must be updated in "not previous value" manner.

Temporary solution before native fix: 

    // update caret position
    DispatchQueue.main.asyncAfter(deadline: .now() + 0.01) {
        let (beginning, end) = (self.beginningOfDocument, self.endOfDocument)

        self.selectedTextRange = self.textRange(from: beginning, to: end)
        self.selectedTextRange = self.textRange(from: end, to: end)
    }
By dimpiax at Aug. 17, 2018, 12:47 p.m. (reply...)

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