使用绑定和结构时自定义 nspopupbutton 标题

Question

如何显示带绑定的时区标识符（使用结构）？例如而不是 Africa/xxx 偏移量 3600 我只想要 Africa/xxx

class TimezonePopupButton: NSPopUpButton {

    private var timezonesController: NSArrayController = NSArrayController()

    private var timeZones : [TimeZone] = {
        var content : [TimeZone] = []
        for identifier in TimeZone.knownTimeZoneIdentifiers {
            if let timeZone = TimeZone(identifier: identifier) {
                content.append(timeZone)
            }
        }
        return content
    }()

    override init(frame frameRect: NSRect) {
        super.init(frame: frameRect)
        commonInit()
    }

    required init?(coder: NSCoder) {
        super.init(coder: coder)
        commonInit()
    }

    func commonInit() {
        timezonesController.content = timeZones
        bind(.content, to: timezonesController, withKeyPath: "arrangedObjects")
        selectItem(withTitle: TimeZone.current.identifier)
    }
}

PS: 可以用这个 hack 来完成，但它看起来很不敏捷，我担心它会在未来崩溃

extension NSTimeZone {

    open override func value(forKey key: String) -> Any? {
        if key == "description" {
            return self.name
        }
        return super.value(forKey: key)
    }
}

Answer 1

绑定contentValues

An array of strings that are displayed as the items in the NSPopUpButton.

bind(.content, to: timezonesController, withKeyPath: "arrangedObjects")
bind(.contentValues, to: timezonesController, withKeyPath: "arrangedObjects.name")

参见NSPopUpButton Bindings。

使用绑定和结构时自定义 nspopupbutton 标题

Custom nspopupbutton title when using bindings and struct

macos

cocoa

timezone

cocoa-bindings

nspopupbutton