UILabel and UITextField 's Insets

in IOS ,We can set Insets for UIButton ,it's called Padding in css  but called Insets in IOS. So UIButton 's Insets property is:

Configuring Edge Insets
contentEdgeInsets  property
titleEdgeInsets  property
imageEdgeInsets  property 

Then  U can use UIEdgeInsetsMake( CGFloat top, CGFloat left, CGFloat bottom, CGFloat right ); to set the Insets for UIButton.

But,there is not Insets for UILabel or UITextField ? if we want use Insets,we should define it bySelf.

step 1: Define InsetLabel class and it's superClass is UILabel ,the code like this:

#import  <UIKit/UIKit.h>
  
 @interface  InsetsLabel : UILabel
 @property(nonatomic) UIEdgeInsets  insets;
 -(id)  initWithFrame:(CGRect)frame andInsets: (UIEdgeInsets)  insets;
 -(id)  initWithInsets: (UIEdgeInsets)  insets;
 @end
  
 //2.  implementation file
 #import  "InsetsLabel.h"
  
 @implementation  InsetsLabel
 @synthesize  insets=_insets;
 -(id)  initWithFrame:(CGRect)frame andInsets:(UIEdgeInsets)insets  {
     self  = [super  initWithFrame:frame];
     if(self){
         self.insets  = insets;
     }
     return  self;
 }
  
 -(id)  initWithInsets:(UIEdgeInsets)insets  {
     self  = [super  init];
     if(self){
         self.insets  = insets;
     }
     return  self;
 }
  
 -(void)  drawTextInRect:(CGRect)rect {
     return  [super  drawTextInRect:UIEdgeInsetsInsetRect(rect, self.insets)];
 }

The importent method is reWrite -(void)drawTextInRect:(CGRect)rect.when you draw label,setting the padding text to bound dispace.

step 2:Define InsetLabel class and it's superClass is UITextField ,the code like this:

 #import  <UIKit/UIKit.h>
  
 @interface  InsetsTextField : UITextField
 @end
  
 @implementation  InsetsTextField
 //控制  placeHolder 的位置，左右缩 20
 -  (CGRect)textRectForBounds:(CGRect)bounds {
     return  CGRectInset( bounds , 20 , 0 );
 }
  
 //  控制文本的位置，左右缩 20
 -  (CGRect)editingRectForBounds:(CGRect)bounds {
     return  CGRectInset( bounds , 20 , 0 );
 }
 @end
  
 //-----------------------------------------------------------------
 //下面是使用  InsetsTextField 的代码，可放在 viewDidLoad 等代理方法中
 InsetsTextField  *insetTextField = [[InsetsTextField alloc]
                                   initWithFrame:CGRectMake(10,  10, 180, 25)];
  
 //须手动设置它的  borderStyle, 不然看不到边框的
 insetsTextField.borderStyle  = UITextBorderStyleRoundedRect;
 [self.view  addSubview:insetsTextField];
 [insetsTextField  release];

This is UILabel and UITextField 's Insets.you can use it if you need.

in the other,UITextField's leftView  and RightView you can use if you want draw image in UITextField's left or right.