This is a loading animation
the triangle has a rotate anmation,but the gif can't show it…you can run the demo see the effect.
add GCLoadingLayer in your view,and set the frame,then startAnimation
self.loadingLayer = [GCLoadingLayer layer];
self.loadingLayer.frame = CGRectMake(GCLoadingLayerCenterX, GCLoadingLayerCenterY, 100, 100);
[self.view.layer addSublayer:self.loadingLayer];
[self.loadingLayer startAnimation];