In order to use closure in argument of UIBarButtonItem
I am using a subclass:
class ActionBarButtonItem: UIBarButtonItem {
private var actionHandler: (() -> Void)?
convenience init(title: String?, style: UIBarButtonItemStyle, actionHandler: (() -> Void)?) {
self.init(title: title, style: style, target: nil, action: #selector(barButtonItemPressed))
self.target = self
self.actionHandler = actionHandler
}
convenience init(image: UIImage?, style: UIBarButtonItemStyle, actionHandler: (() -> Void)?) {
self.init(image: image, style: style, target: nil, action: #selector(barButtonItemPressed))
self.target = self
self.actionHandler = actionHandler
}
@objc func barButtonItemPressed(sender: UIBarButtonItem) {
actionHandler?()
}
}
but now I need to weak [weak self]
:
self.add(barButton: .menu, position: .left) { [weak self] in
guard let strongSelf = self else {return}
strongSelf.openMenu()
}
is there a way to still use closure as selector but not save the closure to avoid using weak self everywhere and you may forget it somewhere ?
In a word, no.
You have to save the closure if you're going to call it later. If you're saving a closure, and that closure refers to self
, you should make self
part of a capture list to avoid a retain cycle. That's what capture lists are for, and is the correct coding pattern for this situation.
Any time you refer to self in a closure you need to stop and think about retain cycles.
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