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 4.2版本:

import UIKit

class InsetTextField: UITextField {

  let inset: CGFloat = 10

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


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

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

}

为UITextField添加填充的一个好方法是子类化UITextField并添加一个edgeInsets属性。然后设置edgeInsets和UITextField将相应地绘制。对于自定义的leftView或rightView集，这也能正确地发挥作用。

OSTextField.h

#import <UIKit/UIKit.h>

@interface OSTextField : UITextField

@property (nonatomic, assign) UIEdgeInsets edgeInsets;

@end

OSTextField.m

#import "OSTextField.h"

@implementation OSTextField

- (id)initWithFrame:(CGRect)frame{
    self = [super initWithFrame:frame];
    if (self) {
        self.edgeInsets = UIEdgeInsetsMake(0, 0, 0, 0);
    }
    return self;
}

-(id)initWithCoder:(NSCoder *)aDecoder{
    self = [super initWithCoder:aDecoder];
    if(self){
        self.edgeInsets = UIEdgeInsetsMake(0, 0, 0, 0);
    }
    return self;
}

- (CGRect)textRectForBounds:(CGRect)bounds {
    return [super textRectForBounds:UIEdgeInsetsInsetRect(bounds, self.edgeInsets)];
}

- (CGRect)editingRectForBounds:(CGRect)bounds {
    return [super editingRectForBounds:UIEdgeInsetsInsetRect(bounds, self.edgeInsets)];
}

@end

在从UITextField派生的类中，至少重写以下两个方法:

- (CGRect)textRectForBounds:(CGRect)bounds;
- (CGRect)editingRectForBounds:(CGRect)bounds;

如果你没有额外的内容，它可能就像这样简单:

return CGRectInset(bounds , 10, 10);

UITextField提供了几个可以覆盖的定位方法。

Swift 5版本的克里斯托弗的答案与额外的用法示例

import UIKit

private class InsetTextField: UITextField {
    var insets: UIEdgeInsets

    init(insets: UIEdgeInsets) {
        self.insets = insets
        super.init(frame: .zero)
    }

    required init(coder aDecoder: NSCoder) {
        fatalError("not intended for use from a NIB")
    }

    // placeholder position
    override func textRect(forBounds bounds: CGRect) -> CGRect {
         return super.textRect(forBounds: bounds.inset(by: insets))
    }
 
    // text position
    override func editingRect(forBounds bounds: CGRect) -> CGRect {
         return super.editingRect(forBounds: bounds.inset(by: insets))
    }
}

extension UITextField {

    class func textFieldWithInsets(insets: UIEdgeInsets) -> UITextField {
        return InsetTextField(insets: insets)
    }

}

用法:-

class ViewController: UIViewController {

  private let passwordTextField: UITextField = {

        let textField = UITextField.textFieldWithInsets(insets: UIEdgeInsets(top: 10, left: 15, bottom: 10, right: 15))
     // ---
   
        return textField
    }()

}

我做到了:

myTextField.layer.sublayerTransform = CATransform3DMakeTranslation(5, 0, 0);

当然记得导入QuartzCore并将框架添加到您的项目中。