iOS系统录屏如何增加雷达波纹效果(从一个点向周围扩散)的简单实现

1.在mian.m中

UIApplicationMain的第三个参数改为MYApplication

int main(int argc, char * argv[]) {
    NSString * appDelegateClassName;
    @autoreleasepool {
        // Setup code that might create autoreleased objects goes here.
        appDelegateClassName = NSStringFromClass([AppDelegate class]);
    }
    return UIApplicationMain(argc, argv, @"MYApplication", appDelegateClassName);
}
           

2.创建MYApplication .h .m

//
//  MYApplication.h
//  kkkvo
//
//  Created by YYY on 2021/8/31.
//  Copyright © 2021 YYY. All rights reserved.
//

#import <UIKit/UIKit.h>

NS_ASSUME_NONNULL_BEGIN

@interface MYApplication : UIApplication

@end

NS_ASSUME_NONNULL_END
           

//
//  MYApplication.m
//  kkkvo
//
//  Created by YYY on 2021/8/31.
//  Copyright © 2021 YYY. All rights reserved.
//

#import "MYApplication.h"

@implementation MYApplication

- (void)sendEvent:(UIEvent *)event{
    [super sendEvent:event];
    
 
    UITouch *touch = [event.allTouches anyObject];
    CGPoint locationPointWindow = [touch preciseLocationInView:touch.window];
    
    UIView *centerRadarView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 7, 7)];
    centerRadarView.centerX = locationPointWindow.x;
    centerRadarView.centerY = locationPointWindow.y;
    centerRadarView.userInteractionEnabled = NO;
    centerRadarView.backgroundColor = [UIColor clearColor];
    centerRadarView.layer.borderColor = [UIColor blackColor].CGColor;
    centerRadarView.layer.borderWidth = 3.5;
    centerRadarView.layer.cornerRadius = 7/2.0;
    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.0001 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
        
        [touch.window addSubview:centerRadarView];
        
        dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.03 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
            [UIView animateWithDuration:0.4 animations:^{
                centerRadarView.width = 25;
                centerRadarView.height = 25;
                centerRadarView.layer.cornerRadius = 25/2.0;
                centerRadarView.centerX = locationPointWindow.x;
                centerRadarView.centerY = locationPointWindow.y;
                centerRadarView.layer.borderWidth = 2;

            } completion:^(BOOL finished) {
                [centerRadarView removeFromSuperview];

            }];
        });

    });

  
}

@end
           

3.原理是获取坐标点，加载到window上显示，通过圆角和宽高的线性动画，实现类似一块石头扔到水里的效果

4.当然可以只在当录屏情况下才添加这个效果，增过录屏的通知方法来打开关闭这个功能。

demo  链接: https://pan.baidu.com/s/1dM8iWK2hU3SupEfngIrOpg 提取码: kd8h 复制这段内容后打开百度网盘手机App，操作更方便哦

。