silica-viewer/SilicaViewer/ExportAccessoryView.swift

import Foundation
import AppKit

class ExportAccessoryView : NSView {
    
    @IBOutlet weak var typeBox: NSPopUpButton!
    
    var savePanel: NSSavePanel? = nil
    
    func setSavePanel(_ savePanel: NSSavePanel?) {
        self.savePanel = savePanel
    }
    
    func setPossibleOptions(_ options : Array<String>) {
        for option in options {
            typeBox.addItem(withTitle: option.uppercased())
        }
    }
    
    @IBAction func changeFileFormat(_ sender: Any) {
        savePanel?.allowedFileTypes?.removeAll()
        savePanel?.allowedFileTypes?.append((typeBox.titleOfSelectedItem?.lowercased())!)
    }
}

extension NSView {
    class func fromNib<T: NSView>() -> T? {
        var topLevelObjects : NSArray?
        guard Bundle.main.loadNibNamed("\(self)", owner: nil, topLevelObjects: &topLevelObjects) else {
            return nil
        }
        return topLevelObjects!.first(where: { $0 is T }) as? T
    }
}