使用 resizableImageWithCapInsets 方法实现可伸缩图片

1 #import <UIKit/UIKit.h>
2 
3 @interface ViewController : UIViewController
4 @end

 1 #import "ViewController.h"
 2 
 3 @interface ViewController ()
 4 - (void)layoutUI;
 5 @end
 6 
 7 @implementation ViewController
 8 #define kWidthOfButton 160.0
 9 #define kHeightOfButton 49.0
10 
11 - (void)viewDidLoad {
12     [super viewDidLoad];
13     
14     [self layoutUI];
15 }
16 
17 - (void)didReceiveMemoryWarning {
18     [super didReceiveMemoryWarning];
19     // Dispose of any resources that can be recreated.
20 }
21 
22 - (void)layoutUI {
23     //普通模式
24     UIImage *img = [UIImage imageNamed:@"blueButton"]; //size: 39*39
25     UIButton *btnNormal = [[UIButton alloc] initWithFrame:CGRectMake(20.0, 40.0, kWidthOfButton, kHeightOfButton)];
26     [btnNormal setTitle:@"btnNormal" forState:UIControlStateNormal];
27     [btnNormal setBackgroundImage:img forState:UIControlStateNormal];
28     [self.view addSubview:btnNormal];
29     
30     //stretchableImageWithLeftCapWidth:topCapHeight:模式（此方法已经过期，推荐用下面的resizableImageWithCapInsets:方法）
31     UIImage *imgStretchable = [img stretchableImageWithLeftCapWidth:16.0 topCapHeight:16.0];
32     UIButton *btnStretchable = [[UIButton alloc] initWithFrame:CGRectMake(20.0, 50.0+kHeightOfButton, kWidthOfButton, kHeightOfButton)];
33     [btnStretchable setTitle:@"btnStretchable" forState:UIControlStateNormal];
34     [btnStretchable setBackgroundImage:imgStretchable forState:UIControlStateNormal];
35     [self.view addSubview:btnStretchable];
36     
37     //resizableImageWithCapInsets:模式；相比stretchableImageWithLeftCapWidth:topCapHeight:模式来说，resizableImageWithCapInsets:模式还能实现类似图片渐变的效果，更灵活控制
38     UIImage *imgResizable = [img resizableImageWithCapInsets:UIEdgeInsetsMake(30.0, 16.0, 9.0, 16.0)];
39     UIButton *btnResizable = [[UIButton alloc] initWithFrame:CGRectMake(20.0, 60.0+(kHeightOfButton*2), kWidthOfButton, kHeightOfButton)];
40     [btnResizable setTitle:@"btnResizable" forState:UIControlStateNormal];
41     [btnResizable setBackgroundImage:imgResizable forState:UIControlStateNormal];
42     [self.view addSubview:btnResizable];
43 }
44 
45 @end