presentModalViewController的动画

转来的，没验证，，，以后有需要的时候在看

self.myPushNav = [[MyPushNavViewController alloc] init];

CATransition *animation = [CATransition animation];

animation.duration = 5.0;

animation.timingFunction = UIViewAnimationCurveEaseInOut;

animation.type = @"pageCurl";

animation.subtype = kCATransitionFromLeft;

[self.view.window.layer addAnimation:animation forKey:nil];

[self presentModalViewController:myPushNav animated:NO];