diff --git a/src/ui/macos.rs b/src/platform/delegate.rs
similarity index 97%
rename from src/ui/macos.rs
rename to src/platform/delegate.rs
index cd0e5871b..01855536e 100644
--- a/src/ui/macos.rs
+++ b/src/platform/delegate.rs
@@ -26,7 +26,7 @@ const SHOW_SETTINGS_TAG: u32 = 2;
 const RUN_ME_TAG: u32 = 3;
 const AWAKE: u32 = 4;
 
-trait AppHandler {
+pub trait AppHandler {
     fn command(&mut self, cmd: u32);
 }
 
@@ -63,9 +63,12 @@ impl AppHandler for Rc<Host> {
 }
 
 // https://github.com/xi-editor/druid/blob/master/druid-shell/src/platform/mac/application.rs
-unsafe fn set_delegate(handler: Option<Box<dyn AppHandler>>) {
-    let mut decl =
-        ClassDecl::new("AppDelegate", class!(NSObject)).expect("App Delegate definition failed");
+pub unsafe fn set_delegate(handler: Option<Box<dyn AppHandler>>) {
+    let decl = ClassDecl::new("AppDelegate", class!(NSObject));
+    if decl.is_none() {
+        return;
+    }
+    let mut decl = decl.unwrap();
     decl.add_ivar::<*mut c_void>(APP_HANDLER_IVAR);
 
     decl.add_method(
diff --git a/src/platform/mod.rs b/src/platform/mod.rs
index ad058d4c0..f2b609d3f 100644
--- a/src/platform/mod.rs
+++ b/src/platform/mod.rs
@@ -11,6 +11,9 @@ pub mod windows;
 #[cfg(target_os = "macos")]
 pub mod macos;
 
+#[cfg(target_os = "macos")]
+pub mod delegate;
+
 #[cfg(target_os = "linux")]
 pub mod linux;
 
diff --git a/src/tray.rs b/src/tray.rs
index 617ec2c93..38ed9b0cb 100644
--- a/src/tray.rs
+++ b/src/tray.rs
@@ -131,6 +131,10 @@ pub fn make_tray() -> hbb_common::ResultType<()> {
 
     let event_loop = EventLoopBuilder::new().build();
 
+    unsafe {
+        crate::platform::delegate::set_delegate(None);
+    }
+
     let tray_menu = Menu::new();
     let quit_i = MenuItem::new(crate::client::translate("Exit".to_owned()), true, None);
     tray_menu.append_items(&[&quit_i]);
diff --git a/src/ui.rs b/src/ui.rs
index 22c44ec5f..f7419cd34 100644
--- a/src/ui.rs
+++ b/src/ui.rs
@@ -20,8 +20,6 @@ use crate::{common::get_app_name, ipc, ui_interface::*};
 mod cm;
 #[cfg(feature = "inline")]
 pub mod inline;
-#[cfg(target_os = "macos")]
-pub mod macos;
 pub mod remote;
 
 pub type Children = Arc<Mutex<(bool, HashMap<(String, String), Child>)>>;
@@ -43,7 +41,7 @@ struct UIHostHandler;
 
 pub fn start(args: &mut [String]) {
     #[cfg(target_os = "macos")]
-    macos::show_dock();
+    crate::platform::delegate::show_dock();
     #[cfg(all(target_os = "linux", feature = "inline"))]
     {
         #[cfg(feature = "appimage")]
@@ -75,7 +73,7 @@ pub fn start(args: &mut [String]) {
     allow_err!(sciter::set_options(sciter::RuntimeOptions::UxTheming(true)));
     frame.set_title(&crate::get_app_name());
     #[cfg(target_os = "macos")]
-    macos::make_menubar(frame.get_host(), args.is_empty());
+    crate::platform::delegate::make_menubar(frame.get_host(), args.is_empty());
     let page;
     if args.len() > 1 && args[0] == "--play" {
         args[0] = "--connect".to_owned();