button action to call a method

Question

I am quite new in iOS development and looking for your advice.

I am looking at one project at GitHub.

I would like to add some functionality. I would like to add a button which will show SideMenu and possibly hide it.

The sideMenu is an instance of class SideMenu and it is created in ViewDidLoad method. How to call sideMenu.toggleMenu(true) method using button's action method.

class HomeViewController: UIViewController, SideMenuDelegate {

    @IBAction func menuButtonTapped(_ sender: Any) {

     sideMenu.toggleMenu(open: true)

    }


    override func viewDidLoad() {
        super.viewDidLoad()

    let sideMenu = SideMenu(menuWidth: 200 , menuItemTitles: ["", "", "Profile", "Settings", "Restaurant"], parentViewController: vviewController)

        sideMenu.menuDelegate = self

}

My button is created using storyboard that is why I can't add it is action method into viewDidLoad.

Theoretically I could create button programmatically in ViewDidLoad. Is it the only solution?

Answer 1

The problem is nothing that do with your button or where you declare it.

sideMenu in your code is a constant of viewDidLoad and not accessible to the IBAction.

Move your definition of sideMenu outside of the method and make it optional:

var sideMenu:SideMenu?

In viewDidLoad set it as you currently are (remove the let)

sideMenu = SideMenu(...

In the IBAction, unwrap the optional to use it:

if let sideMenu = sideMenu {
    // do what you need with sideMenu
else {
    // handle error sideMenu not initialised properly
}

See vacawama's comments for alternatives.