venera/macos/Runner/AppDelegate.swift

import Cocoa
import FlutterMacOS

@main
class AppDelegate: FlutterAppDelegate {
  var flutterResult: FlutterResult?
  var directoryPath: URL!

  override func applicationDidFinishLaunching(_ notification: Notification) {
      let controller: FlutterViewController = mainFlutterWindow?.contentViewController as! FlutterViewController
      let methodChannel = FlutterMethodChannel(name: "venera/method_channel", binaryMessenger: controller.engine.binaryMessenger)

      methodChannel.setMethodCallHandler { (call, result) in
        switch call.method {
        case "getProxy":
            if let proxySettings = CFNetworkCopySystemProxySettings()?.takeUnretainedValue() as NSDictionary? {
                if let httpProxy = proxySettings[kCFNetworkProxiesHTTPProxy] as? String,
                   let httpPort = proxySettings[kCFNetworkProxiesHTTPPort] as? Int {
                    let proxyConfig = "\(httpProxy):\(httpPort)"
                    result(proxyConfig)
                } else if let socksProxy = proxySettings[kCFNetworkProxiesSOCKSProxy] as? String,
                          let socksPort = proxySettings[kCFNetworkProxiesSOCKSPort] as? Int {
                    let proxyConfig = "\(socksProxy):\(socksPort)"
                    result(proxyConfig)
                } else {
                    result("")
                }
            } else {
                result("")
            }
        case "getDirectoryPath":
          self.flutterResult = result
          self.getDirectoryPath()
        case "stopAccessingSecurityScopedResource":
          self.directoryPath?.stopAccessingSecurityScopedResource()
          result(nil)
        default:
          result(FlutterMethodNotImplemented)
        }
      }
    }

  func getDirectoryPath() {
      let openPanel = NSOpenPanel()
      openPanel.canChooseDirectories = true
      openPanel.canChooseFiles = false
      openPanel.allowsMultipleSelection = false

      openPanel.begin { (result) in
          if result == .OK {
              self.directoryPath = openPanel.urls.first
              if let directoryPath = self.directoryPath, !directoryPath.startAccessingSecurityScopedResource() {
                  self.flutterResult?(nil)
                  return
              }
              self.flutterResult?(self.directoryPath?.path)
          } else {
              self.flutterResult?(nil)
          }
      }
  }

  override func applicationShouldTerminateAfterLastWindowClosed(_ sender: NSApplication) -> Bool {
    return true
  }
}