Swift - 将带有 AttributedString 的 URL 添加到 UITextView

Question

当我按下按钮时，我正在尝试向我的 uitextview 添加一个链接。

到目前为止，我已经做到了，但是如果我开始在 UITextView 中编辑文本，它会继续作为链接。

我有很多人设法通过为属性文本添加一个范围来进行排序，这很有效，但是如果我返回并删除例如 URL(attributedString) 文本现在又是一个属性字符串(link) ...

这是我的一些代码：

  @IBAction func webLink(_ sender: Any) {
        let alertController = UIAlertController(title: "Insert Link", message: "", preferredStyle: .alert)


        alertController.addTextField { (textField) in
            textField.placeholder = "URL"
            textField.keyboardType = .URL

        }

        alertController.addTextField { (textField) in
            textField.placeholder = "Link name"
            textField.keyboardType = .default
        }

        let cancelAction = UIAlertAction(title: "Cancel", style: .cancel) { (action) in
            self.dismiss(animated: true, completion: nil)
        }

        let insertAction = UIAlertAction(title: "Insert", style: .default) { (action) in


            let systemFont = self.Text.font!
            let linkAttributes = [
                NSFontAttributeName : systemFont,
                NSLinkAttributeName: NSURL(string: alertController.textFields![0].text!)!] as [String : Any]

            let myAttributes2 = [ NSForegroundColorAttributeName: customGreen ]
            let attributedString = NSMutableAttributedString(string: "\(alertController.textFields![1].text!)   ")

            // Set the 'click here' substring to be the link
            attributedString.setAttributes(linkAttributes, range: NSMakeRange(0, 3))

            self.Text.linkTextAttributes = myAttributes2
            self.Text.textStorage.insert(attributedString, at: self.Text.selectedRange.location)

            let cursor = NSRange(location: self.Text.selectedRange.location + "\(alertController.textFields![1].text!)   ".characters.count, length: 0)
            self.Text.selectedRange = cursor
            self.Text.font = systemFont

        }

        alertController.addAction(cancelAction)
        alertController.addAction(insertAction)


        self.present(alertController, animated: true) {
        }


     }

Answer 1

您需要使用 UITextView 委托功能：

func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {...}

在该函数中，您不能用您的属性覆盖插入“”（空格）字符。

About string attributes

Swift 3 中的完整示例

ViewController.swift

import UIKit

class ViewController: UIViewController, UITextViewDelegate {

@IBOutlet var textView: UITextView!

override func viewDidLoad() {
    super.viewDidLoad()
    self.textView.delegate = self
}

@IBAction func webLink(_ sender: AnyObject) {
    let alertController = UIAlertController(title: "Insert Link", message: "", preferredStyle: .alert)

    alertController.addTextField { (textField) in
        textField.placeholder = "URL"
        textField.keyboardType = .URL
    }

    alertController.addTextField { (textField) in
        textField.placeholder = "Link name"
        textField.keyboardType = .default
    }

    let cancelAction = UIAlertAction(title: "Cancel", style: .cancel) { (action) in
        self.dismiss(animated: true, completion: nil)
    }

    let insertAction = UIAlertAction(title: "Insert", style: .default) { (action) in

        if let urlName = alertController.textFields![1].text {

            let systemFont = self.textView.font!
            let linkAttributes = [
                NSFontAttributeName : systemFont,
                NSLinkAttributeName: NSURL(string: alertController.textFields![0].text!)!] as [String : Any]

            let myAttributes2 = [ NSForegroundColorAttributeName: UIColor.green]

            let attributedString = NSMutableAttributedString(string: urlName)

            // Set the 'click here' substring to be the link
            attributedString.setAttributes(linkAttributes, range: NSMakeRange(0, urlName.characters.count))

            self.textView.linkTextAttributes = myAttributes2
            self.textView.textStorage.insert(attributedString, at: self.textView.selectedRange.location)

            let cursor = NSRange(location: self.textView.selectedRange.location + urlName.characters.count, length: 0)
            self.textView.selectedRange = cursor
            self.textView.font = systemFont
        }
    }

    alertController.addAction(cancelAction)
    alertController.addAction(insertAction)

    self.present(alertController, animated: true) {}
}
    func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {

    if text == " " {
        let attributes = [NSForegroundColorAttributeName: UIColor.black, NSFontAttributeName: self.textView.font!] as [String : Any]
        let attributedString = NSMutableAttributedString(string: text, attributes: attributes)
        self.textView.textStorage.insert(attributedString, at: range.location)
        let cursor = NSRange(location: self.textView.selectedRange.location+1, length: 0)
        textView.selectedRange = cursor
        return false
    }
    return true
}
}

Main.storyboard

<?xml version="1.0" encoding="UTF-8"?>
<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="11201" systemVersion="16A323" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" colorMatched="YES" initialViewController="BYZ-38-t0r">
<dependencies>
    <deployment identifier="iOS"/>
    <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="11161"/>
    <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
</dependencies>
<scenes>
    <!--View Controller-->
    <scene sceneID="tne-QT-ifu">
        <objects>
            <viewController id="BYZ-38-t0r" customClass="ViewController" customModule="stackoverflow_40611248" customModuleProvider="target" sceneMemberID="viewController">
                <layoutGuides>
                    <viewControllerLayoutGuide type="top" id="y3c-jy-aDJ"/>
                    <viewControllerLayoutGuide type="bottom" id="wfy-db-euE"/>
                </layoutGuides>
                <view key="view" contentMode="scaleToFill" id="8bC-Xf-vdC">
                    <rect key="frame" x="0.0" y="0.0" width="375" height="667"/>
                    <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
                    <subviews>
                        <button opaque="NO" contentMode="scaleToFill" contentHorizontalAlignment="center" contentVerticalAlignment="center" buttonType="roundedRect" lineBreakMode="middleTruncation" translatesAutoresizingMaskIntoConstraints="NO" id="MAb-bM-rda">
                            <state key="normal" title="Button"/>
                            <connections>
                                <action selector="webLink:" destination="BYZ-38-t0r" eventType="touchUpInside" id="lEW-xK-QqL"/>
                            </connections>
                        </button>
                        <textView clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="scaleToFill" textAlignment="natural" translatesAutoresizingMaskIntoConstraints="NO" id="NfR-7H-lIY">
                            <color key="backgroundColor" white="1" alpha="1" colorSpace="calibratedWhite"/>
                            <constraints>
                                <constraint firstAttribute="width" constant="240" id="oZX-gx-ivA"/>
                            </constraints>
                            <string key="text">Lorem ipsum dolor sit er elit lamet, consectetaur cillium adipisicing pecu, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. Nam liber te conscient to factor tum poen legum odioque civiuda.</string>
                            <fontDescription key="fontDescription" type="system" pointSize="14"/>
                            <textInputTraits key="textInputTraits" autocapitalizationType="sentences"/>
                        </textView>
                    </subviews>
                    <color key="backgroundColor" red="1" green="1" blue="1" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
                    <constraints>
                        <constraint firstItem="MAb-bM-rda" firstAttribute="centerY" secondItem="8bC-Xf-vdC" secondAttribute="centerY" id="EUe-Ac-j39"/>
                        <constraint firstItem="NfR-7H-lIY" firstAttribute="top" secondItem="y3c-jy-aDJ" secondAttribute="bottom" constant="162" id="LtY-X7-xvc"/>
                        <constraint firstItem="MAb-bM-rda" firstAttribute="centerX" secondItem="8bC-Xf-vdC" secondAttribute="centerX" id="XWA-IA-8Bd"/>
                        <constraint firstItem="MAb-bM-rda" firstAttribute="top" secondItem="NfR-7H-lIY" secondAttribute="bottom" constant="8" symbolic="YES" id="cUB-uR-AvM"/>
                        <constraint firstItem="NfR-7H-lIY" firstAttribute="centerX" secondItem="MAb-bM-rda" secondAttribute="centerX" id="pyb-a7-lJG"/>
                    </constraints>
                </view>
                <connections>
                    <outlet property="textView" destination="NfR-7H-lIY" id="vYj-cp-6P8"/>
                </connections>
            </viewController>
            <placeholder placeholderIdentifier="IBFirstResponder" id="dkx-z0-nzr" sceneMemberID="firstResponder"/>
        </objects>
    </scene>
</scenes>
</document>