使用 Swift 在带有属性文本的 UITextView 中的光标点设置特定字体大小

Question

I am trying to build a RichTextEditor using UITextView. When I apply a different font size at the end of the text, it fails to update the font size for new text typed.

I am currently having the below code which I tried to make it work:

Rich text outlet is
@IBOutlet weak var richTextView: UITextView!

The code for trying to change the font is

func setAttributesForSelectedTextRange(_ attributes: [NSAttributedString.Key: Any]) {
    if let text = richTextView.attributedText.mutableCopy() as? NSMutableAttributedString, let selectedRange = richTextView.selectedTextRange {
        let cursorPosition = richTextView.offset(from: richTextView.beginningOfDocument, to: selectedRange.start)
        text.addAttributes(attributes, range: richTextView.selectedRange)
        if selectedRange.end == richTextView.endOfDocument {
            text.append(NSAttributedString(string: "", attributes: attributes))
        }

        richTextView.attributedText = text
    }
}

I tried adding an empty string to the end with new attributes, but that didn't work out. How do I achieve setting the attribute change in the above example?

Answer 1

it fails to update the font size for new text typed.

The way to set the attributes of the text that the user will type is to set the UITextView's typingAttributes .

https://developer.apple.com/documentation/uikit/uitextview/1618629-typingattributes