怎么实现presentModalViewController的push效果

替换前：
[[UIApplication sharedApplication].keyWindow.rootViewController presentModalViewController: picker animated: YES];
替换后：
[[UIApplication sharedApplication].keyWindow.rootViewController presentViewController: picker animated: YES completion:nil];
有一警告：
Instance method '-presentedViewController:animated:completion:' not found (return type defaults to 'id')

请问各位，如何替换才为正解？文档已提供

presentModalViewController:animated:
Presents a modal view managed by the given view controller to the user. (Deprecated in iOS 6.0. Use presentViewController:animated:completion: instead.)

- (void)presentModalViewController:(UIViewController *)modalViewController animated:(BOOL)animated

presentViewController:animated:completion:
Presents a view controller.

- (void)presentViewController:(UIViewController *)viewControllerToPresent animated:(BOOL)flag completion:(void (^)(void))completion
Parameters
viewControllerToPresent
The view controller being presented.
flag
Pass YES to animate the presentation; otherwise, pass NO.
completion
A completion handler or NULL.