截取屏幕

 

UIWindow *screenWindow = [[UIApplication sharedApplication] keyWindow];
    UIGraphicsBeginImageContext(screenWindow.frame.size);
    [screenWindow.layer renderInContext:UIGraphicsGetCurrentContext()];
    UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    pcVC.view.backgroundColor =  [UIColor colorWithPatternImage:viewImage];