SWRevealViewController - reveal it manually under @IBAction

Question

This is my StartViewController with simple @IBAction:

class StartViewController: UIViewController {

    @IBAction func startButtonTapped(sender: UIButton) {
        revealViewController().revealToggleAnimated(true) //error
    }
}

Along with the commented line there is an error:

fatal error: unexpectedly found nil while unwrapping an Optional value

What am I doing wrong?

Of course StartViewController is presented from SWRevealViewController via sw_front segue.

For some reason revealViewController() returns nil here. Why?

This is how my storyboard looks like:

I think you are just missing the SWRevealViewControllerDelegate in your class. Try the following — SoundShock, Jun 14 '16 at 08:17

Yury · Answer 1 · 2016-06-14T09:08:31.910

2

When you implementing SWRevealViewController using storyboard, you should set Storyboard Entry Point to SWRevealViewController instance (Reveal View Controller on picture), not to front view controller (Start View Controller on picture).

Note that revealViewController method return optional pointer, and even when all is set properly it return nil until view is loaded, so you better use optional chaining:

revealViewController()?.revealToggleAnimated(true)

edited Jun 14 '16 at 09:08

answered Jun 14 '16 at 08:18

Yury

6,044
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No, I call it when I tap the button. So it is far away after view did load. – Bartłomiej Semańczyk Jun 14 '16 at 08:22
Confirm please, that `revealViewController` method return `nil`: `if revealViewController() == nil {print("reveal init error")}` – Yury Jun 14 '16 at 08:25
exactly. When I type here `po revealViewController() == nil` it prints `true`. – Bartłomiej Semańczyk Jun 14 '16 at 08:27
Did you set "sw_rear" segue also? You sure that you did not forgot to set `Class` field to `SWRevealViewController` in main reveal controller in storyboard? You sure also, that you used custom "set" segues? – Yury Jun 14 '16 at 08:32
Yes, I did everything right. Can I share my project with you via github? – Bartłomiej Semańczyk Jun 14 '16 at 08:36
sure, I have time to check it – Yury Jun 14 '16 at 08:37
https://github.com/kunass2/SWRevealViewController. It is installed via cocoapods. It should be simple for you:) very thx – Bartłomiej Semańczyk Jun 14 '16 at 08:39
Let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/114593/discussion-between-bartlomiej-semanczyk-and-shadow-of). – Bartłomiej Semańczyk Jun 14 '16 at 08:41
1

@BartłomiejSemańczyk just move your storyboard entry point (arrow) from Start Vew Controller to Reveal View Controller – Yury Jun 14 '16 at 08:41
1

You are amazing man:) How could I miss that?:) it works:) I really appreciate that. – Bartłomiej Semańczyk Jun 14 '16 at 08:43
Please update your answer, depending on my updated question. I will accept it. – Bartłomiej Semańczyk Jun 14 '16 at 08:45
@BartłomiejSemańczyk done. Also I still recommend you to use optional chaining, since you still can get nil from this method in some cases =) – Yury Jun 14 '16 at 08:52
I will do it like this:) – Bartłomiej Semańczyk Jun 14 '16 at 08:53

score 0 · Answer 2 · answered Jun 14 '16 at 08:19

0

I think your app might crash because you are missing a delegate.Try to add the following to your protocols:

class StartViewController: UIViewController,SWRevealViewControllerDelegate {

    @IBAction func startButtonTapped(sender: UIButton) {
        revealViewController().revealToggleAnimated(true) //error
    }
}

If it still crashes, try changing the revealViewController().revealToggleAnimated(true) with revealViewController().revealToggle(self) and see if it still crashes.

answered Jun 14 '16 at 08:19

SoundShock

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It still crashes for both methods. – Bartłomiej Semańczyk Jun 14 '16 at 08:21
add this to the code `revealViewController().delegate = self` – SoundShock Jun 14 '16 at 08:22
No, stll crashes. I dont think, that delegate matters here. For some reason `revealViewController()` returns nil, when it should not. – Bartłomiej Semańczyk Jun 14 '16 at 08:23
You did put the `revealViewController().delegate = self` in your `viewDidLoad()`, right? Not in the button action. It should matter, because if you don't do the delegate, sw_front isn't enabled when the menu is shown in the back. – SoundShock Jun 14 '16 at 08:25
Yes, I did it in viewDidLoad() but now crash appears in that method, because `revealViewController()` returns nil. – Bartłomiej Semańczyk Jun 14 '16 at 08:29
In that case, it isn't the code itself, but something might be wrong with the segues in your storyboard. Did you check this question: http://stackoverflow.com/questions/34987122/revealviewcontroller-always-returns-nil ? – SoundShock Jun 14 '16 at 08:31

SWRevealViewController - reveal it manually under @IBAction

2 Answers2