以编程方式在 UIView 上添加 UITextField Swift

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【中文标题】以编程方式在 UIView 上添加 UITextField Swift【英文标题】：Adding UITextField on UIView Programmatically Swift 【发布时间】：2014-07-12 05:45:58 【问题描述】：

我是 Swift 和 ios 编程的新手。我试图使用 Swift 以编程方式创建一个UITextField，但不能完全正确。另外，如何将其更改为具有半透明效果以淡入背景？

var myField: UITextField = UITextField (frame:CGRectMake(10, 10, 30, 10));
self.addSubview(myField)

【问题讨论】：

【参考方案1】：

Swift 3 和 Swift 4.2：

override func viewDidLoad() 
    super.viewDidLoad()

    let sampleTextField =  UITextField(frame: CGRect(x: 20, y: 100, width: 300, height: 40))
    sampleTextField.placeholder = "Enter text here"
    sampleTextField.font = UIFont.systemFont(ofSize: 15)
    sampleTextField.borderStyle = UITextField.BorderStyle.roundedRect
    sampleTextField.autocorrectionType = UITextAutocorrectionType.no
    sampleTextField.keyboardType = UIKeyboardType.default
    sampleTextField.returnKeyType = UIReturnKeyType.done
    sampleTextField.clearButtonMode = UITextField.ViewMode.whileEditing
    sampleTextField.contentVerticalAlignment = UIControl.ContentVerticalAlignment.center
    sampleTextField.delegate = self
    self.view.addSubview(sampleTextField)

委托方法：

// MARK:- ---> UITextFieldDelegate

extension ViewController: UITextFieldDelegate 

    func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool 
        // return NO to disallow editing.
        print("TextField should begin editing method called")
        return true
    

    func textFieldDidBeginEditing(_ textField: UITextField) 
        // became first responder
        print("TextField did begin editing method called")
    

    func textFieldShouldEndEditing(_ textField: UITextField) -> Bool 
        // return YES to allow editing to stop and to resign first responder status. NO to disallow the editing session to end
        print("TextField should snd editing method called")
        return true
    

    func textFieldDidEndEditing(_ textField: UITextField) 
        // may be called if forced even if shouldEndEditing returns NO (e.g. view removed from window) or endEditing:YES called
        print("TextField did end editing method called")
    

    func textFieldDidEndEditing(_ textField: UITextField, reason: UITextFieldDidEndEditingReason) 
        // if implemented, called in place of textFieldDidEndEditing:
        print("TextField did end editing with reason method called")
    

    func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool 
        // return NO to not change text
        print("While entering the characters this method gets called")
        return true
    

    func textFieldShouldClear(_ textField: UITextField) -> Bool 
        // called when clear button pressed. return NO to ignore (no notifications)
        print("TextField should clear method called")
        return true
    

    func textFieldShouldReturn(_ textField: UITextField) -> Bool 
        // called when 'return' key pressed. return NO to ignore.
        print("TextField should return method called")
        // may be useful: textField.resignFirstResponder()
        return true
    



// MARK: UITextFieldDelegate <---

Swift 2.0：

let sampleTextField = UITextField(frame: CGRectMake(20, 100, 300, 40))
sampleTextField.placeholder = "Enter text here"
sampleTextField.font = UIFont.systemFontOfSize(15)
sampleTextField.borderStyle = UITextBorderStyle.RoundedRect
sampleTextField.autocorrectionType = UITextAutocorrectionType.No
sampleTextField.keyboardType = UIKeyboardType.Default
sampleTextField.returnKeyType = UIReturnKeyType.Done
sampleTextField.clearButtonMode = UITextFieldViewMode.WhileEditing;
sampleTextField.contentVerticalAlignment = UIControlContentVerticalAlignment.Center
sampleTextField.delegate = self
self.view.addSubview(sampleTextField)

委托方法：

    // MARK:- ---> Textfield Delegates
    func textFieldDidBeginEditing(textField: UITextField) 
        print("TextField did begin editing method called")
    

    func textFieldDidEndEditing(textField: UITextField) 
        print("TextField did end editing method called")
    

    func textFieldShouldBeginEditing(textField: UITextField) -> Bool 
        print("TextField should begin editing method called")
        return true;
    

    func textFieldShouldClear(textField: UITextField) -> Bool 
        print("TextField should clear method called")
        return true;
    

    func textFieldShouldEndEditing(textField: UITextField) -> Bool 
        print("TextField should snd editing method called")
        return true;
    

    func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool 
        print("While entering the characters this method gets called")
        return true;
    

    func textFieldShouldReturn(textField: UITextField) -> Bool 
        print("TextField should return method called")
        textField.resignFirstResponder();
        return true;
    
    // MARK: Textfield Delegates <---

【讨论】：

我能够以编程方式创建文本字段，但是我在哪里或如何为这个文本字段创建一个出口？当按下按钮时，我需要读取此字段中的值运行一些代码。 没关系，我想通了。就像sampleTextField.text 一样简单:) 如何以编程方式添加多个文本字段？如果有输入则在循环中 @XcodianSolangi 在这里查看：gist.github.com/AshokKumarYes/f064f25787607cca46932fc76555be26【参考方案2】： 
self.addSubview(myTextField)

仅当您使用 UIView 的子类时才有效。

您必须将其添加为 ViewController 层次结构的 UIView 的子视图。

var txtField: UITextField = UITextField(frame: CGRect(x: 0, y: 0, width: 500.00, height: 30.00));
self.view.addSubview(txtField)

默认背景颜色为白色，它可能不会出现。您需要提供样式以及文本颜色和背景颜色。

txtField.borderStyle = UITextBorderStyle.Line
txtField.text = "myString" 
txtField.backgroundColor = UIColor.redColor()

欲了解更多信息，here

【讨论】：

也不应该是 let 而不是 var 吗？- 你仍然可以更改类属性，而且不太可能需要重新分配。【参考方案3】：

为 Swift 3 和 Xcode 8.2 更新

    let stepsTextField = UITextField(frame: CGRect(x: 20, y: 100, width: 300, height: 40))
    stepsTextField.placeholder = "Enter text here"
    stepsTextField.font = UIFont.systemFont(ofSize: 15)
    stepsTextField.borderStyle = UITextBorderStyle.roundedRect
    stepsTextField.autocorrectionType = UITextAutocorrectionType.no
    stepsTextField.keyboardType = UIKeyboardType.default
    stepsTextField.returnKeyType = UIReturnKeyType.done
    stepsTextField.clearButtonMode = UITextFieldViewMode.whileEditing;
    stepsTextField.contentVerticalAlignment = UIControlContentVerticalAlignment.center

【讨论】：

【参考方案4】：

试试下面的代码

var textFiled = UITextField(frame: CGRectMake(20.0, 30.0, 100.0, 33.0))
        textFiled.backgroundColor = UIColor.redColor()
        textFiled.borderStyle = UITextBorderStyle.Line
        self.view.addSubview(textFiled)

【讨论】：

【参考方案5】：

您可以在 Swift 5.2 中使用以下代码：

lazy var titleTextField:UITextField = 
    let textField = UITextField()
    textField.translatesAutoresizingMaskIntoConstraints = false
    textField.placeholder = "Title *"
    textField.keyboardType = UIKeyboardType.default
    textField.returnKeyType = UIReturnKeyType.done
    textField.autocorrectionType = UITextAutocorrectionType.no
    textField.font = UIFont.systemFont(ofSize: 13)
    textField.borderStyle = UITextField.BorderStyle.roundedRect
    textField.clearButtonMode = UITextField.ViewMode.whileEditing;
    textField.contentVerticalAlignment = UIControl.ContentVerticalAlignment.center
    return textField
()

【讨论】：

【参考方案6】：

您需要将文本字段添加到self.view 而不是self。

var myField: UITextField = UITextField (frame:CGRectMake(10, 10, 30, 10));
self.view.addSubview(myField)

关于添加半透明模糊效果已经有一些建议，你可以通过 -

UIView border with fade or blur effect

【讨论】：

【参考方案7】：

在 UIView 上添加 textField 是

var textField=UITextField(frame:CGRectMake(x,y,width,height));
self.view.addSubView(textField)

【讨论】：

【参考方案8】：

确保您在 viewDidLoad() 中，然后只需添加以下代码即可生成一个 textField：

let myTextField: UITextField = UITextField(frame: CGRect(x: 0, y: 0, width: 200.00, height: 40.00));
    self.view.addSubview(myTextField)

    myTextField.backgroundColor = UIColor.redColor()
    myTextField.text = "some string"
    myTextField.borderStyle = UITextBorderStyle.Line

【讨论】：

【参考方案9】：

在viewDidLoad()中编写代码并实现委托UITextFieldDelegate

let _textField: UITextField = UITextField(frame: CGRect(x: 0, y: 0, width: 200.00, height: 40.00))
_textField.backgroundColor = UIColor.redColor()
_textField.text = "some string"
_textField.delegate = self
_textField.borderStyle = UITextBorderStyle.Line
self.view.addSubview(_textField)

【讨论】：

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