iOS Swift：选中JLAttributedTextView文本后内容全部变白问题求助

Hey there! Let's figure out why your JLAttributedTextView (inside JLStickerTextView) turns all white when text is selected. This is a common issue tied to how the text view handles attributed string styles during selection, so let's break down the fixes step by step.

1. Explicitly Set Selection Text Attributes #

The most likely culprit is missing configuration for how text should look when selected. UITextView has a selectedTextAttributes property that lets you define the foreground and background color for selected text. Add this to your JLAttributedTextView setup:

// In your JLAttributedTextView subclass or initialization code
override init(frame: CGRect, textContainer: NSTextContainer?) {
    super.init(frame: frame, textContainer: textContainer)
    setupSelectionStyles()
}

required init?(coder: NSCoder) {
    super.init(coder: coder)
    setupSelectionStyles()
}

private func setupSelectionStyles() {
    // Set the tint color (cursor and selection highlight border color)
    self.tintColor = UIColor.systemBlue
    
    // Define exactly how selected text should appear
    self.selectedTextAttributes = [
        NSAttributedString.Key.foregroundColor: UIColor.white, // Adjust to your preferred text color
        NSAttributedString.Key.backgroundColor: UIColor.systemBlue // Adjust to your preferred highlight color
    ]
}

This overrides any default or inherited styles that might be forcing the text to turn white without a visible background.

2. Check for Conflicting Attributed String Attributes #

Sometimes the base attributed text you're setting might have attributes that clash with selection styles. For example, if your normal text uses a white color, but the selection background is also light, it could look like everything is white. Verify your attributed string setup:

// Example of creating a safe attributed string
let yourText = "Sample text for JLAttributedTextView"
let baseAttributes: [NSAttributedString.Key: Any] = [
    .foregroundColor: UIColor.black, // Ensure normal text color is visible
    .font: UIFont.systemFont(ofSize: 16)
]
let attributedText = NSAttributedString(string: yourText, attributes: baseAttributes)
yourAttributedTextView.attributedText = attributedText

Make sure there's no logic that resets the text color when the selection changes.

3. Inspect JLStickerTextView's Custom Logic #

Since JLAttributedTextView is part of the JLStickerTextView component, check if the parent class or the subclass has custom code that modifies text attributes on selection:

• Look for overrides of textViewDidChangeSelection(_:) in any delegate implementations
• Check if layoutSubviews or textDidChange methods are altering the attributed text's color
• If this is a third-party library, browse its source code for references to selectedTextRange or forced color changes

4. Debug the Attributed Text in Selection State #

To pinpoint the issue, add a breakpoint in the textViewDidChangeSelection(_:) delegate method and print the attributed text's properties:

func textViewDidChangeSelection(_ textView: UITextView) {
    guard let attributedText = textView.attributedText else { return }
    attributedText.enumerateAttributes(in: NSRange(location: 0, length: attributedText.length), options: []) { attributes, range, stop in
        print("Range \(range): Attributes \(attributes)")
    }
}

This will show you if the foregroundColor is being set to white across all ranges when selection happens, which would confirm where the override is occurring.

内容的提问来源于stack exchange，提问作者Ahsan Aasim