dismissModalViewController with transition: left t

问题:

I was using a nice method to dismiss my modal view controller:

[self dismissModalViewControllerWithTransition:2];

which makes a slide transition from left to right, like a navigation controller does to pop a view.

As this method is a non-public method, apple will not accept it. How can I program this kind of animation in my code (slide from left to right, to dismiss a modal view, and slide from right to left to present a modal view) ?

Thanks in advance

回答1:

I have accepted the answer from Safecase, but I would like to publish my final solution here:

1) To present a modal view controller with a from right to left transition I have written following method:

-(void) presentModalView:(UIViewController *)controller {
    CATransition *transition = [CATransition animation];
    transition.duration = 0.35;
    transition.timingFunction =
    [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
    transition.type = kCATransitionMoveIn;
    transition.subtype = kCATransitionFromRight;

    // NSLog(@"%s: self.view.window=%@", _func_, self.view.window);
    UIView *containerView = self.view.window;
    [containerView.layer addAnimation:transition forKey:nil];
    [self presentModalViewController:controller animated:NO];
}

2) To dismiss a modal view with an slide transition left to right:

-(void) dismissMe {
    CATransition *transition = [CATransition animation];
    transition.duration = 0.35;
    transition.timingFunction =
    [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
    transition.type = kCATransitionMoveIn;
    transition.subtype = kCATransitionFromLeft;

    // NSLog(@"%s: controller.view.window=%@", _func_, controller.view.window);
    UIView *containerView = self.view.window;
    [containerView.layer addAnimation:transition forKey:nil];

    [self dismissModalViewControllerAnimated:NO];
}

Thanks guys!

回答2:

Try this:

I asume you are dismissing a view controller 2 from view controller 1. In view controller 2 you are using this

[self  dismissModalViewControlleAnimated: NO]];

Now In the first view controller, in viewWillAppear: method add the code

CATransition *animation = [CATransition animation];

[animation setDelegate:self];
[animation setType:kCATransitionPush];
[animation setSubtype:kCATransitionFromLeft];

[animation setDuration:0.50];
[animation setTimingFunction:
 [CAMediaTimingFunction functionWithName:
  kCAMediaTimingFunctionEaseInEaseOut]];


[self.view.layer addAnimation:animation forKey:kCATransition];

回答3:

This Swift 4 ModalService class below is a pre-packaged flexible solution that can be dropped into a project and called from anywhere it is required. This class brings the modal view in on top of the current view from the specified direction, and then moves it out to reveal the original view behind it when it exits. Given a presentingViewController that is currently being displayed and a modalViewController that you have created and wish to display, you simply call:

ModalService.present(modalViewController, presenter: presentingViewController)

Then, to dismiss, call:

ModalService.dismiss(modalViewController)

This can of course be called from the modalViewController itself as ModalService.dismiss(self). Note that dismissing does not have to be called from the presentingViewController, and does not require knowledge of or a reference to the original presentingViewController.

The class provides sensible defaults, including transitioning the modal view in from the right and out to the left. This transition direction can be customised by passing a direction, which can be customised for both entry and exit:

ModalService.present(modalViewController, presenter: presentingViewController, enterFrom: .left)

and

ModalService.dismiss(self, exitTo: .left)

This can be set as .left, .right, .top and .bottom. You can likewise pass a custom duration in seconds if you wish:

ModalService.present(modalViewController, presenter: presentingViewController, enterFrom: .left, duration: 0.5)

and

ModalService.dismiss(self, exitTo: .left, duration: 2.0)

Head nod to @jcdmb for the Objective C answer on this question which formed the kernel of the solution in this class.

---

Here's the full class. The values returned by the private transitionSubtype look odd but are set this way deliberately. You should test the observed behaviour before assuming these need 'correcting'. :)

import UIKit

class ModalService {

    enum presentationDirection {
        case left
        case right
        case top
        case bottom
    }

    class func present(_ modalViewController: UIViewController,
                       presenter fromViewController: UIViewController,
                       enterFrom direction: presentationDirection = .right,
                       duration: CFTimeInterval = 0.3) {
        let transition = CATransition()
        transition.duration = duration
        transition.timingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseInEaseOut)
        transition.type = kCATransitionMoveIn
        transition.subtype = ModalService.transitionSubtype(for: direction)
        let containerView: UIView? = fromViewController.view.window
        containerView?.layer.add(transition, forKey: nil)
        fromViewController.present(modalViewController, animated: false)
    }

    class func dismiss(_ modalViewController: UIViewController,
                       exitTo direction: presentationDirection = .right,
                       duration: CFTimeInterval = 0.3) {
        let transition = CATransition()
        transition.duration = duration
        transition.timingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseInEaseOut)
        transition.type = kCATransitionReveal
        transition.subtype = ModalService.transitionSubtype(for: direction, forExit: true)
        if let layer = modalViewController.view?.window?.layer {
            layer.add(transition, forKey: nil)
        }
        modalViewController.dismiss(animated: false)
    }

    private class func transitionSubtype(for direction: presentationDirection, forExit: Bool = false) -> String {
        if (forExit == false) {
            switch direction {
            case .left:
                return kCATransitionFromLeft
            case .right:
                return kCATransitionFromRight
            case .top:
                return kCATransitionFromBottom
            case .bottom:
                return kCATransitionFromTop
            }
        } else {
            switch direction {
            case .left:
                return kCATransitionFromRight
            case .right:
                return kCATransitionFromLeft
            case .top:
                return kCATransitionFromTop
            case .bottom:
                return kCATransitionFromBottom
            }
        }
    }
}