iOS 裁剪图片

////  ViewController.m//  test_btn_image_01////  Created by cdd on 16/7/4.//  Copyright © 2016年 jeffasd. All rights reserved.//#import "ViewController.h"@interface ViewController ()@end@implementation ViewController- (void)viewDidLoad {    [super viewDidLoad];        //    UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];//    //    //    //    button.frame = CGRectMake(100, 200, 200, 80);//    button.backgroundColor = [UIColor cyanColor];//    //    UIImage *btnImage = [UIImage imageNamed:@"right"];//    //    [button setImage:[UIImage imageNamed:@"right"] forState:UIControlStateNormal];//    //    [button setTitle:@"发布" forState:UIControlStateNormal];//    //    ////    [button setImageEdgeInsets:UIEdgeInsetsMake(0, btnImage.size.width, 0, btnImage.size.width)];//    //    [button setImageEdgeInsets:UIEdgeInsetsMake(0, btnImage.size.width, 0, -btnImage.size.width)];//    //    [self.view addSubview:button];    }- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{        //    [self cropImage:50 Image:[self imageWithColor:[UIColor cyanColor]]];        [self cropImage:50 UIColor:[UIColor cyanColor]];    }- (UIImage *)cropImage:(CGFloat)width UIColor:(UIColor *)color {    UIGraphicsBeginImageContextWithOptions(CGSizeMake(width, width), NO, 0.0);    CGContextRef context = UIGraphicsGetCurrentContext();//    CGContextSaveGState(context);    CGContextSetFillColorWithColor(context, [UIColor cyanColor].CGColor);    CGContextFillRect(context, CGRectMake(0, 0, width, width));    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();    UIGraphicsBeginImageContextWithOptions(CGSizeMake(width, width), NO, 0.0);    CGContextRef ctx=UIGraphicsGetCurrentContext();//    CGContextRestoreGState(context);    CGContextAddEllipseInRect(ctx, CGRectMake(0, 0, width, width));    CGContextClip(ctx);//    [image drawAtPoint:CGPointMake(0, 0)];    CGContextDrawImage(ctx, CGRectMake(0, 0, width, width), image.CGImage);    UIImage *newimage = UIGraphicsGetImageFromCurrentImageContext();            return newimage;            #if 0        CGFloat borderW = 0;//    1.开启一个和原始图片一样大小的位图上下文.    CGSize size = CGSizeMake(image.size.width + 2 *borderW, image.size.height + 2 * borderW);    UIGraphicsBeginImageContextWithOptions(size,NO,0);        CGContextRef context = UIGraphicsGetCurrentContext();    //    2.绘制一个大圆,填充//    UIBezierPath *path = [UIBezierPath bezierPathWithOvalInRect:CGRectMake(0, 0, size.width, size.height)];//    [[UIColor blueColor] set];//    [path fill];//    3.添加一个裁剪区域.//    UIBezierPath *path = [UIBezierPath bezierPathWithOvalInRect:CGRectMake(borderW, borderW, image.size.width, image.size.height)];//    [path addClip];            CGContextAddEllipseInRect(context, CGRectMake(borderW, borderW, image.size.width, image.size.height));    //    //    CGContextClip(context);        //    4.把图片绘制到裁剪区域当中.    [image drawAtPoint:CGPointMake(borderW, borderW)];//    5.生成一张新图片.    UIImage *clipImage = UIGraphicsGetImageFromCurrentImageContext();//    6.关闭上下文.    UIGraphicsEndImageContext();        return clipImage;#endif    }- (UIImage *)imageWithColor:(UIColor *)color{        CGFloat width = 50;        UIGraphicsBeginImageContextWithOptions(CGSizeMake(width, width), NO, 0.0);        CGContextRef context = UIGraphicsGetCurrentContext();        CGContextSetFillColorWithColor(context, [UIColor cyanColor].CGColor);        CGContextFillRect(context, CGRectMake(0, 0, width, width));        UIImage *image = UIGraphicsGetImageFromCurrentImageContext();        return image;}- (void)didReceiveMemoryWarning {    [super didReceiveMemoryWarning];    // Dispose of any resources that can be recreated.}@end