UIActivityIndicatorView(菊花)

#import "ViewController.h"

@interface ViewController ()

@property (nonatomic,strong) UIActivityIndicatorView *activityIndicatorView;
@property (nonatomic,assign) BOOL isOn;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    [self.view addSubview:self.activityIndicatorView];
}

- (UIActivityIndicatorView *)activityIndicatorView {
    if (!_activityIndicatorView) {
        _activityIndicatorView = [[UIActivityIndicatorView alloc] init];
        _activityIndicatorView.center = CGPointMake([UIScreen mainScreen].bounds.size.width/2, [UIScreen mainScreen].bounds.size.height/2);//只能设置中心，不能设置大小
        _activityIndicatorView.color = [UIColor redColor]; // 改变圈圈的颜色为红色； iOS5引入
        _activityIndicatorView.activityIndicatorViewStyle = UIActivityIndicatorViewStyleLarge;// 中号,大号
        [_activityIndicatorView startAnimating]; // 开始旋转
        [_activityIndicatorView setHidesWhenStopped:YES]; //当旋转结束时隐藏
    }
    return _activityIndicatorView;
}

- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event {
    _isOn = !_isOn;
    if (_isOn) {
        [self.activityIndicatorView stopAnimating];
    } else {
        [self.activityIndicatorView startAnimating];
    }
}

@end