UIActivityIndicatorView和UIActivityViewController区别

UIActivityIndicatorView是一个等待指示器(菊花)。

//在.h中声明一个属性：
@property (nonatomic, strong)UIActivityIndicatorView *activityIndicatorView;

//在.m中初始化：
   _activityIndicatorView = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle: UIActivityIndicatorViewStyleWhiteLarge];
    _activityIndicatorView.center = self.view.center;
    _activityIndicatorView.autoresizingMask = UIViewAutoresizingFlexibleTopMargin | UIViewAutoresizingFlexibleBottomMargin | UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin;
    
  [self.view addSubview:_activityIndicatorView];

//在需要用的地方：
[_activityIndicatorView startAnimating]; //开始
[_activityIndicatorView stopAnimating]; //停止

UIActivityViewController是苹果自带的分享页面,类似友盟分享,但不需要到第三方平台申请AppKey，直接分享，十分方便。其分享图片需要将图片转为NSData，分享视频只需拿到视频的URL即可。

- (void)shareVideo {
        NSURL *URL = [NSURL fileURLWithPath:_assetModel.filePath];
        UIActivityViewController *activityVc = [[UIActivityViewController alloc] initWithActivityItems:@[URL] applicationActivities:nil];
        [self presentViewController:activityVc animated:YES completion:nil];
}