学习使用viewController转场效果，学习交流
参考这篇：http://www.raywenderlich.com/86521/how-to-make-a-view-controller-transition-animation-like-in-the-ping-app
简单的学习，将swift改成oc
扩展学习：尝试边缘手势， //边界手势 UIScreenEdgePanGestureRecognizer *edgePanGestureRecognizer = [[UIScreenEdgePanGestureRecognizer alloc]initWithTarget:self action:@selector(panGesture:)]; //设置从什么边界滑入 edgePanGestureRecognizer.edges = UIRectEdgeLeft; [_navigationController.view addGestureRecognizer:edgePanGestureRecognizer];