抛出另一个不需要子类化的解决方案:

UITextField *txtField = [UITextField new];
txtField.borderStyle = UITextBorderStyleRoundedRect;

// grab BG layer
CALayer *bgLayer = txtField.layer.sublayers.lastObject;
bgLayer.opacity = 0.f;

// add new bg view
UIView *bgView = [UIView new];
bgView.backgroundColor = [UIColor whiteColor];
bgView.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;
bgView.userInteractionEnabled = NO;

[txtField addSubview: bgView];
[txtField sendSubviewToBack: bgView];

在iOS 7和iOS 8上测试。这两个工作。苹果仍然有可能修改UITextField的层层次结构，把事情搞砸了。

抛出另一个不需要子类化的解决方案:

UITextField *txtField = [UITextField new];
txtField.borderStyle = UITextBorderStyleRoundedRect;

// grab BG layer
CALayer *bgLayer = txtField.layer.sublayers.lastObject;
bgLayer.opacity = 0.f;

// add new bg view
UIView *bgView = [UIView new];
bgView.backgroundColor = [UIColor whiteColor];
bgView.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;
bgView.userInteractionEnabled = NO;

[txtField addSubview: bgView];
[txtField sendSubviewToBack: bgView];

在iOS 7和iOS 8上测试。这两个工作。苹果仍然有可能修改UITextField的层层次结构，把事情搞砸了。

斯威夫特

 class TextField: UITextField {

    let inset: CGFloat = 8

    // placeholder position
    override func textRect(forBounds bounds: CGRect) -> CGRect {
        return bounds.insetBy(dx: inset, dy: inset)
    }

    // text position
    override func editingRect(forBounds bounds: CGRect) -> CGRect {
        return bounds.insetBy(dx: inset, dy: inset)
    }
}

我想我可以提供一个快速解决方案

import UIKit

class TextField: UITextField {
    let inset: CGFloat = 10

    // placeholder position
    override func textRectForBounds(bounds: CGRect) -> CGRect {
        return CGRectInset(bounds , inset , inset)
    }

    // text position
    override func editingRectForBounds(bounds: CGRect) -> CGRect {
        return CGRectInset(bounds , inset , inset)
    }

    override func placeholderRectForBounds(bounds: CGRect) -> CGRect {
        return CGRectInset(bounds, inset, inset) 
    }
}

斯威夫特 3+

import UIKit

class TextField: UITextField {
    let inset: CGFloat = 10

    // placeholder position
    override func textRect(forBounds: CGRect) -> CGRect {
        return forBounds.insetBy(dx: self.inset , dy: self.inset)
    }

    // text position
    override func editingRect(forBounds: CGRect) -> CGRect {
        return forBounds.insetBy(dx: self.inset , dy: self.inset)
    }

    override func placeholderRect(forBounds: CGRect) -> CGRect {
        return forBounds.insetBy(dx: self.inset, dy: self.inset)
    }
}

Swift 3 /可在界面构建器中设计/单独的水平和垂直昆虫/可用

@IBDesignable
class TextFieldWithPadding: UITextField {

@IBInspectable var horizontalInset: CGFloat = 0
@IBInspectable var verticalInset: CGFloat = 0

override func textRect(forBounds bounds: CGRect) -> CGRect {
    return bounds.insetBy(dx: horizontalInset, dy: verticalInset)
}

override func editingRect(forBounds bounds: CGRect) -> CGRect {
    return bounds.insetBy(dx: horizontalInset , dy: verticalInset)
}

override func placeholderRect(forBounds bounds: CGRect) -> CGRect {
    return bounds.insetBy(dx: horizontalInset, dy: verticalInset)
}
}

用法:

&

@IBInspectable， @IBDesignable swift类怎么样?

@IBDesignable
class TextField: UITextField {
    @IBInspectable var insetX: CGFloat = 6 {
       didSet {
         layoutIfNeeded()
       }
    }
    @IBInspectable var insetY: CGFloat = 6 {
       didSet {
         layoutIfNeeded()
       }
    }

    // placeholder position
    override func textRectForBounds(bounds: CGRect) -> CGRect {
        return CGRectInset(bounds , insetX , insetY)
    }

    // text position
    override func editingRectForBounds(bounds: CGRect) -> CGRect {
        return CGRectInset(bounds , insetX , insetY)
    }
}

你会在你的故事板中看到这个。

更新- Swift 3

@IBDesignable
class TextField: UITextField {
    @IBInspectable var insetX: CGFloat = 0
    @IBInspectable var insetY: CGFloat = 0

    // placeholder position
    override func textRect(forBounds bounds: CGRect) -> CGRect {
        return bounds.insetBy(dx: insetX, dy: insetY)
    }

    // text position
    override func editingRect(forBounds bounds: CGRect) -> CGRect {
        return bounds.insetBy(dx: insetX, dy: insetY)
    }
}