可点击 @、# 标记文本实现

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
import UIKit

enum wordType{
    case hashtag   // #标示文本类型
    case mention   // @标示文本类型
}

／/自定义视图用于高亮 # 和 @ 之后的文本（效果类似于微博、twitter），并添加点击事件
class AttrTextView: UITextView {
    var textString: NSString?
    var attrString: NSMutableAttributedString?
    var callBack: ((String, wordType) -> Void)?
    
    ...
}

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
public func setText(text: String,normalColor: UIColor, hashtagColor: UIColor, mentionColor: UIColor,  normalFont: UIFont, hashTagFont: UIFont, mentionFont: UIFont,tapCallBack callBack: @escaping (String, wordType) -> Void) {
    self.callBack = callBack
    self.attrString = NSMutableAttributedString(string: text)
    self.textString = NSString(string: text)
    
    // Set initial font attributes for our string
    // 设置字体和文本颜色
    attrString?.addAttribute(NSFontAttributeName, value: normalFont, range: NSRange(location: 0, length: (textString?.length)!))
    attrString?.addAttribute(NSForegroundColorAttributeName, value: normalColor, range: NSRange(location: 0, length: (textString?.length)!))
    
    // Call a custom set Hashtag and Mention Attributes Function
    // 设置 #、@ 的高亮色等属性
    setAttrWithName(attrName: "Hashtag", wordPrefix: "#", color: hashtagColor, text: text, font: hashTagFont)
    setAttrWithName(attrName: "Mention", wordPrefix: "@", color: mentionColor, text: text, font: mentionFont)
    
    // Add tap gesture that calls a function tapRecognized when tapped
    // 添加手势
    let tapper = UITapGestureRecognizer(target: self, action: #selector(self.tapRecognized(tapGesture:)))
    addGestureRecognizer(tapper)
}

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
private func setAttrWithName(attrName: String, wordPrefix: String, color: UIColor, text: String, font: UIFont) {
    // Words can be separated by either a space or a line break
    // 将文本按照空格和 n 键拆分为单词数组
    var words: [String] = []
    let wordtext: [String] = text.components(separatedBy: " ")
    for var word in wordtext {
        
        if word.hasPrefix("n") {
            word = word.replacingOccurrences(of: "n", with: "")
        }
        words.append(word)
        
    }
    
    // 便利数组，检查是否满足条件并进行属性设置
    for word in words.filter({$0.hasPrefix(wordPrefix)}) {
        let range = textString!.range(of: word)
        attrString?.addAttribute(NSForegroundColorAttributeName, value: color, range: range)
        attrString?.addAttribute(attrName, value: 1, range: range)
        attrString?.addAttribute("Clickable", value: 1, range: range)
        attrString?.addAttribute(NSFontAttributeName, value: font, range: range)
    }
    self.attributedText = attrString
}

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
func tapRecognized(tapGesture: UITapGestureRecognizer) {
    var wordString: String?         // The String value of the word to pass into callback function
    var char: NSAttributedString!   //The character the user clicks on. It is non optional because if the user clicks on nothing, char will be a space or " "
    var word: NSAttributedString?   //The word the user clicks on
    var isHashtag: AnyObject?
    var isAtMention: AnyObject?
        
    // Gets the range of the character at the place the user taps
    // 检查用户点击字符的范围
    let point = tapGesture.location(in: self)
    let charPosition = closestPosition(to: point)
        
        
    guard let charRange = tokenizer.rangeEnclosingPosition(charPosition!, with: .character, inDirection: 1) else {
        return
    }
        
    let location = offset(from: beginningOfDocument, to: charRange.start)
    let length = offset(from: charRange.start, to: charRange.end)
    let attrRange = NSMakeRange(location, length)
    char = attributedText.attributedSubstring(from: attrRange)
        
    // If the user has not clicked on anything, exit the function
    if char.string == " "{
        print("User clicked on nothing")
        return
    }
        
    // Checks the character's attribute, if any
    // 检查属性标示
    isHashtag = char?.attribute("Hashtag", at: 0, longestEffectiveRange: nil, in: NSMakeRange(0, char!.length)) as AnyObject?
    isAtMention = char?.attribute("Mention", at: 0, longestEffectiveRange: nil, in: NSMakeRange(0, char!.length)) as AnyObject?
        
        
        
    // Gets the range of the word at the place user taps
    // 获得点击单词的范围
    let wordRange = tokenizer.rangeEnclosingPosition(charPosition!, with: .word, inDirection: 1)
        
        
    /*
    单词的范围在下面两种情况下为 nil:
    1. 点击在 "#" or "@" 标示上
    2. 没有点击在任何字符上。但是这种情况在上面的代码中已经排除了，所有只剩下 1
    */
    if wordRange != nil {
        let wordLocation = offset(from: beginningOfDocument, to: wordRange!.start)
        let wordLength = offset(from: wordRange!.start, to: wordRange!.end)
        let wordAttrRange = NSMakeRange(wordLocation, wordLength)
        word = attributedText.attributedSubstring(from: wordAttrRange)
        wordString = word!.string
    } else {
        /*
        右移12像素后再获取单词
        */
        var modifiedPoint = point
         modifiedPoint.x += 12
        let modifiedPosition = closestPosition(to: modifiedPoint)
        let modifedWordRange = tokenizer.rangeEnclosingPosition(modifiedPosition!, with: .word, inDirection: 1)
        if modifedWordRange != nil {
            let wordLocation = offset(from: beginningOfDocument, to: modifedWordRange!.start)
            let wordLength = offset(from: modifedWordRange!.start, to: modifedWordRange!.end)
            let wordAttrRange = NSMakeRange(wordLocation, wordLength)
            word = attributedText.attributedSubstring(from: wordAttrRange)
            wordString = word!.string
        }
    }
        
    if let stringToPass = wordString {
        // 点击回掉函数
        if isHashtag != nil && callBack != nil {
            callBack!(stringToPass, wordType.hashtag)
        } else if isAtMention != nil && callBack != nil {
            callBack!(stringToPass, wordType.mention)
        }
    }
}

1
2
3
4
5
6
7
let attrView = AttrTextView.init(frame: CGRect.init(x: 0, y: 64, width: view.bounds.size.width, height: view.bounds.size.height - 64), textContainer: nil)
    self.view.addSubview(attrView)
      
attrView.setText(text: "#PHP 是不是世界上最好的语言？ @all ",normalColor: .black, hashtagColor: .red, mentionColor: .blue, normalFont: UIFont.systemFont(ofSize: 10), hashTagFont:  UIFont.systemFont(ofSize: 14), mentionFont:  UIFont.systemFont(ofSize: 14)) { word,wordType in
    print(word)
}