Swift 2，使用Objective-C选择器'setOn:'的方法'setOn'与使用相同Objective-C选择器的'on'设置方法发生冲突 [英] Swift 2, method 'setOn' with Objective-C selector 'setOn:' conflicts with setter for 'on' with the same Objective-C selector

问题描述

迅速2，我有一个从objc的UIView继承的类，它具有"on"变量，以及相关的方法"setOn:animated"和"setOn:"，如下所示:

Swift 2, I have a class inherits from objc's UIView and it has 'on' variable, and related methods 'setOn:animated' and 'setOn:' like below:

public class AView: UIView {
var on: Bool = false

public func setOn(on: Bool, animated: Bool) {
    self.on = on
    // do something more about animating
}

public func setOn(on: Bool) {
    setOn(on, animated: false)
}

我收到一条错误消息:method 'setOn' with Objective-C selector 'setOn:' conflicts with setter for 'on' with the same Objective-C selector

And I got an error message: method 'setOn' with Objective-C selector 'setOn:' conflicts with setter for 'on' with the same Objective-C selector

我认为willSet或didSet不是解决方案，因为即使添加了一些保护条件，setOn:animated:也被调用了两次:

I think willSet or didSet is not a solution because setOn:animated: is called twice even if I add some guard conditions:

var on: Bool = false {
    willSet {
        if self.on != newValue {
            setOn(self.on, animated: false)
        }
    }
}
....
....
let a = AView()
a.setOn(true, animated: true) // setOn:animated: is called twice

有没有不更改变量名和方法名的解决方案吗?

Is there a solution without changing a variable name and methods name?

解决方法:我的解决方案是添加额外的内部变量，并使用计算属性将其公开.我不喜欢添加额外的变量，肯定会有更好的解决方案.

Workaround: My solution is add extra internal variable and expose it with computed property. I don't like adding extra variable and definitely there will be a better solution.

private var isOn: Bool = false
var on: Bool {
    set(newOn) {
        setOn(newOn, animated: false)
    }
    get {
        return isOn
    }
}

public func setOn(on: Bool, animated: Bool) {
    self.isOn = on
    // do something ...
}

推荐答案

类似于

Similarly as in Compiler error: Method with Objective-C selector conflicts with previous declaration with the same Objective-C selector, you can also hide properties from the Objective-C runtime with @nonobjc:

public class AView: UIView {
    @nonobjc var on: Bool = false

    public func setOn(on: Bool, animated: Bool) {
        self.on = on
        // do something more about animating
    }

    public func setOn(on: Bool) {
        setOn(on, animated: false)
    }
}

这可以防止自动生成有冲突的Objective-C设置器.

which prevents a conflicting Objective-C setter from being auto-generated.

这篇关于Swift 2，使用Objective-C选择器'setOn:'的方法'setOn'与使用相同Objective-C选择器的'on'设置方法发生冲突的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！