swift中UITextField的使用

UITextField的使用

mport UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        
        self.setupTextField()
    }
    
    func setupTextField() {
        // 创建textField
        let textField = UITextField(frame: CGRect(x: 100, y: 100, width: 100, height: 40))
        // 设置输入框的边框样式
        /**
         public enum UITextBorderStyle : Int {
         case none  无边框
         case line  直线边框
         case bezel 边线+阴影
         case roundedRect   圆角矩形边框
         }
         */
        textField.borderStyle = .none
        // 设置提示文字
        textField.placeholder = "请输入相关文字"
        // 设置使用*** 显示, 如密码
        textField.isSecureTextEntry = true
        // 当文字超出文本框宽度时，自动调整文字大小
        textField.adjustsFontSizeToFitWidth = true
        // 最小可缩小的字号
        textField.minimumFontSize = 12.0
        // 水平对齐
        /**
         public enum NSTextAlignment : Int {
         
         case left // Visually left aligned
         case center // Visually centered
         case right // Visually right aligned
         case justified // Fully-justified. The last line in a paragraph is natural-aligned.
         case natural // Indicates the default alignment for script
         }
         */
        textField.textAlignment = .center
        // 垂直对齐
        /**
         public enum UIControlContentVerticalAlignment : Int {
         
         case center    垂直居中对齐
         case top       垂直向上对齐
         case bottom    垂直向下对齐
         case fill
         }

         */
        textField.contentVerticalAlignment = .top
        
        // 设置背景图片，先要去除边框样式
        textField.borderStyle = .none
        textField.background = UIImage(named: "back")
        // 清除按钮
        /**
         public enum UITextFieldViewMode : Int {
         
         case never         从不出现
         case whileEditing  编辑时出现清除按钮
         case unlessEditing 编辑时不出现，编辑后才出现清除按钮
         case always        一直显示清除按钮
         }
         */
        textField.clearButtonMode = .whileEditing
        // 键盘类型
        /**
         public enum UIKeyboardType : Int {
         
         
         case `default` // Default type for the current input method.   系统默认的虚拟键盘
         case asciiCapable // Displays a keyboard which can enter ASCII characters  显示英文字母的虚拟键盘
         case numbersAndPunctuation // Numbers and assorted punctuation.    显示数字和标点的虚拟键盘
         case URL // A type optimized for URL entry (shows . / .com prominently).   显示便于输入数字的虚拟键盘
         case numberPad // A number pad with locale-appropriate digits (0-9, ۰-۹, ०-९, etc.). Suitable for PIN entry.   显示便于输入数字的虚拟键盘
         case phonePad // A phone pad (1-9, *, 0, #, with letters under the numbers).   显示便于拨号呼叫的虚拟键盘
         case namePhonePad // A type optimized for entering a person's name or phone number.    显示便于聊天拨号的虚拟键盘
         case emailAddress // A type optimized for multiple email address entry (shows space @ . prominently).  显示便于输入Email的虚拟键盘
         @available(iOS 4.1, *)
         case decimalPad // A number pad with a decimal point.  显示用于输入数字和小数点的虚拟键盘
         @available(iOS 5.0, *)
         case twitter // A type optimized for twitter text entry (easy access to @ #)   显示方便些Twitter的虚拟键盘
         @available(iOS 7.0, *)
         case webSearch // A default keyboard type with URL-oriented addition (shows space . prominently).  显示便于在网页上书写的虚拟键盘
         @available(iOS 10.0, *)
         case asciiCapableNumberPad // A number pad (0-9) that will always be ASCII digits.
         public static var alphabet: UIKeyboardType { get } // Deprecated
         }
         */
        textField.keyboardType = .default
        // 成为第一响应者
        textField.becomeFirstResponder()
        // 放弃第一响应者
        textField.resignFirstResponder()
        // 设置键盘return键的样式
        /**
         public enum UIReturnKeyType : Int {
         
         case `default`
         case go    表示完成输入，同时会跳到另一页
         case google
         case join  表示注册用户或添加数据
         case next  表示继续下一步
         case route
         case search    表示搜索
         case send  表示继续下一步
         case yahoo
         case done  表示完成输入
         case emergencyCall
         @available(iOS 9.0, *)
         case `continue`
         }
         */
        textField.returnKeyType = .done
        // 设置代理
        textField.delegate = self
        
        // 设置attributedPlaceholder
        // 1. 创建属性字典，存放需要修改的属性
        var attributed:[String: AnyObject] = NSMutableDictionary() as! [String: AnyObject]
        attributed[NSFontAttributeName] = UIFont.systemFont(ofSize: 13)
        // 2. 创建带属性的字符串
        let string:NSAttributedString = NSAttributedString.init(string: "你还好嘛，hello world", attributes: attributed)
        // 3. 设置placeholder属性
        textField.attributedPlaceholder = string
        
        /**
         public enum UITextFieldViewMode : Int {
         
         case never
         case whileEditing
         case unlessEditing
         case always
         }
         */
        textField.leftView = UIView(frame: CGRect(x: 0, y: 0, width: 30, height: 30))
        textField.leftViewMode = .always
        
        
        self.view.addSubview(textField)
        
    
    }

}

extension ViewController: UITextFieldDelegate {

    // 点击return键时调用
    func textFieldShouldReturn(_ textField: UITextField) -> Bool {
        return true
    }
    
    // 将要开始输入的时候调用
    func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool {
        
        return true
    }
    
    // 已经开始输入
    func textFieldDidBeginEditing(_ textField: UITextField) {
        
    }
    
    // 将要结束输入时调用
    func textFieldShouldEndEditing(_ textField: UITextField) -> Bool {
       return true
    }
    
    // 已经输入结束
    func textFieldDidEndEditing(_ textField: UITextField) {
        
    }
    
    // 清除文字按钮的点击事件
    func textFieldShouldClear(_ textField: UITextField) -> Bool {
        return true
    }
    
}