使文本视图响应用户键入的文本

Question

我的应用程序中有一个文本视图，允许用户在其中键入任何内容。我希望文本视图在输入时检测到一些单词并改变它们的颜色。

例如，如果用户输入-"My favourite colour is red"，那么我希望单词'red'得到文本颜色'red'。但是，thus 应该在句子中输入 red 之后立即发生。我应该如何实施？

Answer 1

你必须使用 attributedText 在 UITextView 委托方法中

- (void)textViewDidChange:(UITextView *)textView

这将解决您的问题。

Answer 2

我认为你应该做的是这个（如果我错了请纠正我，因为我没有 Xcode 在这台计算机上进行测试，但这应该可以工作）。如果这不起作用，请执行 Fawad Masud 并将其添加到视图中并加载...

 yourTextView.addTarget(self, action: "textViewDidChange:",forControlEvents: UIControlEvents.EditingChanged)

override func viewDidLoad() {
    super.viewDidLoad()
    yourTextView.delegate = self //Basically makes the function below applicable to this textview
}

func textViewDidChange(textView: UITextView) { //Every time text changes this code is run
   var textViewText = yourTextView.text as NSString!

if textViewText.containsString("red") {
      textViewText.textColor = UIColor.redColor()

   }
}

Answer 3

textField.addTarget(self, action: "textFieldDidChange:",forControlEvents: UIControlEvents.EditingChanged)

func textFieldDidChange(textField: UITextField) {
//your code

var main_string = textField.text
var string_to_color = "red"

var range = (main_string as NSString).rangeOfString(string_to_color)

var attributedString = NSMutableAttributedString(string:main_string)
attributedString.addAttribute(NSForegroundColorAttributeName, value: UIColor.redColor() , range: range)

}

Answer 4

你需要三样东西：

在界面生成器中，您需要使用其中一种委托方法。我认为 "editingChanged" 是这里最好的。从带有 "ctrl" 的文本字段拖动到您的文档。
您需要一种方法来遍历文本字段中的字符串并检测单词。

componentsSeparatedByCharactersInSet
您需要一种为句子中的单词设置样式的方法。

NSMutableAttributedString

也很有趣：

部分代码（扔在操场上）：

这会找到所有要更改的词，但会删除分隔符。需要做更多工作才能完成代码。

var strSeperator : NSCharacterSet = NSCharacterSet(charactersInString: ",.:;?! ")

var strArray = str.componentsSeparatedByCharactersInSet(strSeperator)

var styledText = NSMutableAttributedString()

for i in 0..<strArray.count {

    let currentWord = strArray[i]
    var currentBoolFoundInControl : Bool = false

    for iB in 0..<colorTheseStrings.count {

        let controlWord = colorTheseStrings[iB]

        if controlWord == currentWord {
            currentBoolFoundInControl = true
            // add to mutable attributed string in a color
        }

    }

    var attrString1 = NSMutableAttributedString(string: "\(strArray[i]) ")

    if currentBoolFoundInControl == true {

        var range = (strArray[i] as NSString).rangeOfString(strArray[i])
        if strArray[i] == "red" {
            attrString1.addAttribute(NSForegroundColorAttributeName, value: UIColor(red: 0.5, green: 0.0, blue: 0.0, alpha: 1.0), range: range)
        } else if strArray[i] == "blue" {
            attrString1.addAttribute(NSForegroundColorAttributeName, value: UIColor(red: 0.0, green: 0.0, blue: 0.5, alpha: 1.0), range: range)

        }
    }

    styledText.appendAttributedString(attrString1)
}

myTextField.attributedText = styledText

还有一种方法：

download it here

我觉得这种方式是最稳健最酷最高效的。代码可以稍微清理一下，可以使用更多 style/flair。这对于 "sky blue" 之类的东西确实有问题，因为它会首先找到 "blue" 并替换它。但我不得不留下一些改进的余地。 ;)

我情不自禁，所以我解决了最后一个问题。

再一次，我修复了，我的修复。现在效率更高，实际上更正了。

第一部分是 HighLighter class，将其放在单独的文档中。

// text hightlighter

class SyntaxGroup {

    var wordCollection : [String] = []
    var type : String = ""
    var color : UIColor = UIColor(red: 1.0, green: 1.0, blue: 1.0, alpha: 1.0)

    init(wordCollection_I : [String], type_I : String, color_I: UIColor) {

        wordCollection = wordCollection_I
        type = type_I
        color = color_I

    }
}

class SyntaxDictionairy {

    var collections : [SyntaxGroup] = []

}

class SyntaxRange {

    var range : NSRange
    var color : UIColor

    init (color_I : UIColor, range_I : NSRange) {
        color = color_I
        range = range_I
    }

}

class HighLighter {

    var ranges : [SyntaxRange] = []
    var baseString : NSMutableString = NSMutableString()
    var highlightedString : NSMutableAttributedString = NSMutableAttributedString()
    var syntaxDictionairy : SyntaxDictionairy

    init (syntaxDictionairy_I : SyntaxDictionairy) {

        syntaxDictionairy = syntaxDictionairy_I

    }

    func run(string : String?, completion: (finished: Bool) -> Void) {

        ranges = [] // reset the ranges, else it crashes when you change a previous part of the text
        highlightedString = NSMutableAttributedString() // make sure all strings start fresh
        baseString = NSMutableString() // make sure all strings start fresh

        // multi threading to prevent locking up the interface with large libraries.
        let qualityOfServiceClass = QOS_CLASS_DEFAULT
        let backgroundQueue = dispatch_get_global_queue(qualityOfServiceClass, 0)
        dispatch_async(backgroundQueue) { () -> Void in

            if string != nil && string != "" {

                self.highlightedString = NSMutableAttributedString(string: string!)

                for i in 0..<self.syntaxDictionairy.collections.count {

                    for iB in 0..<self.syntaxDictionairy.collections[i].wordCollection.count {

                        let currentWordToCheck = self.syntaxDictionairy.collections[i].wordCollection[iB]
                        self.baseString = NSMutableString(string: string!)

                        while self.baseString.containsString(self.syntaxDictionairy.collections[i].wordCollection[iB]) {

                            let nsRange = (self.baseString as NSString).rangeOfString(currentWordToCheck)
                            let newSyntaxRange = SyntaxRange(color_I: self.syntaxDictionairy.collections[i].color, range_I: nsRange)
                            self.ranges.append(newSyntaxRange)

                            var replaceString = ""
                            for _ in 0..<nsRange.length {
                                replaceString += "§" // secret unallowed character
                            }
                            self.baseString.replaceCharactersInRange(nsRange, withString: replaceString)
                        }
                    }
                }
                for i in 0..<self.ranges.count {

                    self.highlightedString.addAttribute(NSForegroundColorAttributeName, value: self.ranges[i].color, range: self.ranges[i].range)

                }
            }

            dispatch_sync(dispatch_get_main_queue()) { () -> Void in

                completion(finished: true)
            }

        }
    }
}

在 ViewController 中：这是您将与 UITextfield 一起使用的代码。首先创建一个荧光笔实例并设置你的单词字典和相应的颜色。然后在需要的时候启动运行函数。

import UIKit

class ViewController: UIViewController {

    @IBOutlet weak var myTextfield: UITextField!

    var syntaxHighLighter : HighLighter! // declare highlighter

    override func viewDidLoad() {
        super.viewDidLoad()
        setUpHighLighter()
    }
    // this is just a little function to put the set up for the highlighter outside of viewDidLoad()
    func setUpHighLighter() {

        // build a dict of words to highlight
        let redColor = UIColor(red: 0.5, green: 0.0, blue: 0.0, alpha: 1.0)
        let blueColor = UIColor(red: 0.0, green: 0.0, blue: 0.5, alpha: 1.0)
        let greenColor = UIColor(red: 0.0, green: 0.5, blue: 0.0, alpha: 1.0)

        let redGroup = SyntaxGroup(wordCollection_I: ["red","bordeaux"], type_I: "Color", color_I: redColor)
        let blueGroup = SyntaxGroup(wordCollection_I: ["coralblue","blue","skyblue","azur"], type_I: "Color", color_I: blueColor)
        let greenGroup = SyntaxGroup(wordCollection_I: ["green"], type_I: "Color", color_I: greenColor)

        let dictionairy : SyntaxDictionairy = SyntaxDictionairy()
        dictionairy.collections.append(blueGroup)
        dictionairy.collections.append(greenGroup)
        dictionairy.collections.append(redGroup)

        syntaxHighLighter = HighLighter(syntaxDictionairy_I: dictionairy)

    }
    // this is where the magic happens, place the code from inside the editingChanged inside your function that responds to text changes.
    @IBAction func editingChanged(sender: UITextField) {

        syntaxHighLighter.run(myTextfield.text) { (finished) -> Void in
            self.myTextfield.attributedText = self.syntaxHighLighter.highlightedString
        }
    }
}

Answer 5

也许你可以实现文本视图委托来检测用户何时完成输入，有条件地询问所写文本是否是你想要的，如果是，则做一些事情（改变颜色）。这里有一些文档 https://developer.apple.com/library/ios/documentation/UIKit/Reference/UITextViewDelegate_Protocol/ 你可以尝试实现这样的东西：

let text: UITextView? //this must be binded with the storyboard ui

//MARK UITextViewDelegate

func textViewDidChange(_ textView: UITextView){
     if (textView.text == "bla"){
         textView.colour == UIColour(Red)
     }
}

此代码只是一个架构。阅读文档并检查语法。希望对你有帮助！！

联邦

使文本视图响应用户键入的文本

Making a text view respond to text typed by the user

uitextview

ios

swift

xcode6