//头文件
#import <UIKit/UIKit.h>
@interface UIImage (Extension)
//传入图片的name.然后返回一个拉伸后的图片(新图片)
+(UIImage *)resizableImage:(NSString *)name;
@end
//实现
#import "UIImage+Extension.h"
@implementation UIImage (Extension)
//用来拉伸图片,图片四周样式不变
+(UIImage *)resizableImage:(NSString *)name{
UIImage *normal = [UIImage imageNamed:name];
CGFloat w = normal.size.width * 0.5;
CGFloat h = normal.size.height * 0.5;
//核心方法,相当于改图片只拉伸内部,外边不变.
return [normal resizableImageWithCapInsets:UIEdgeInsetsMake(h, w, h, w)];
}
@end