原理就是俩张图片叠在一起，去除上面图片的效果。
000.gif
代码如下
//
// ViewController.m
// 05-图片擦除(了解)
//
// Created by 李亮 on 2016/12/1.
// Copyright © 2016年 www.thelast.com. All rights reserved.
//
#import "ViewController.h"
@interface ViewController ()
@property (weak, nonatomic) IBOutlet UIImageView *imgView;
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
self.imgView.userInteractionEnabled = YES;
UIPanGestureRecognizer * pan = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(pan:)];
[self.imgView addGestureRecognizer:pan];
}
- (void)pan:(UIPanGestureRecognizer *)pan{
CGPoint p = [pan locationInView:self.imgView];
CGFloat wh = 20;
CGFloat x = p.x - wh * 0.5;
CGFloat y = p.y - wh * 0.5;
CGRect rect = CGRectMake(x, y, wh, wh);
//获取图片的上下文
UIGraphicsBeginImageContextWithOptions(self.imgView.bounds.size, NO, 0);
CGContextRef ctx = UIGraphicsGetCurrentContext();
[self.imgView.layer renderInContext:ctx];
CGContextClearRect(ctx, rect);
UIImage * newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
self.imgView.image = newImage;
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
@end
代码链接
下载地址 demo
