iOS开发：用CATransition改变PUSH的弹出方向

问题：项目中页面跳转需要用模态效果（页面上下进入推出），但是进来的页面还还是需要导航。

使用的是导航跳转（左右出现）页面，效果是模态效果（上下）出现页面

PUSH 推入：模拟出模态弹出效果

• (void)PushPresent {

TWOViewController *vc = [TWOViewController new];

CATransition *transition = [CATransition animation];

transition.duration = 0.25;

transition.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionDefault];

transition.type = kCATransitionPush;

transition.subtype = kCATransitionFromTop;

transition.delegate = self;

[self.navigationController.view.layer addAnimation:transition forKey:nil];

//隐藏跳转的页面的导航条：实质是PUSH，所以用POP 推出

[self.navigationController pushViewController:vc animated:NO];

}
pop 弹出：模拟出模态弹出效果

• (void)popDissmiss{

CATransition *transition = [CATransition animation];

transition.duration = 0.25;

transition.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionDefault];

transition.type = kCATransitionPush;

transition.subtype = kCATransitionFromBottom;

transition.delegate = self;

[self.navigationController.view.layer addAnimation:transition forKey:nil];

self.navigationController.navigationBarHidden = NO;

[self.navigationController popViewControllerAnimated:NO];

}