UIActivityIndicatorView1.activityIndicatorViewStyle设置指示器的样式UIActivityIndicatorViewStyleWhiteLargeUIActivityIndicatorViewStyleWhite(默认样式)UIActivityIndicatorViewStyleGray2.hidesWhenStopped当停止动画的时候，是否隐藏。默认为YES。3.实例化指示器对象，根据样式设置尺寸，不需要手动设置。-(id)initWithActivityIndicatorStyle:(UIActivityIndicatorViewStyle)style;4.开启动画-(void)startAnimating;5.关闭动画-(void)stopAnimating;6.是否在动画-(BOOL)isAnimating;7.UIActivityIndicatorView使用注意7.1初始化的时候不需要设置尺寸，设置尺寸也没有效果。7.2必须调用startAnimating才会显示UIActivityIndicatorView//初始化指示器UIActivityIndicatorView*indicator=[[UIActivityIndicatorViewalloc]initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];//设置指示器位置indicator.center=CGPointMake(self.view.frame.size.width*0.5,self.view.frame.size.height*0.5);//开启动画，必须调用，否则无法显示[indicatorstartAnimating];[self.viewaddSubview:indicator];
