feat: add menu hide, show and remove (#8)

examples/winit.rs

@@ -13,10 +13,10 @@ fn main() {
     let mut event_loop_builder = EventLoopBuilder::new();
 
     let mut menu_bar = Menu::new();
-    let menu_bar_c = menu_bar.clone();
 
     #[cfg(target_os = "windows")]
     {
+        let menu_bar_c = menu_bar.clone();
         event_loop_builder.with_msg_hook(move |msg| {
             use windows_sys::Win32::UI::WindowsAndMessaging::{TranslateAcceleratorW, MSG};
             unsafe {
@@ -26,6 +26,7 @@ fn main() {
             }
         });
     }
+
     #[allow(unused_mut)]
     let mut event_loop = event_loop_builder.build();
     #[cfg(target_os = "macos")]
@@ -51,6 +52,11 @@ fn main() {
         menu_bar.init_for_hwnd(_window2.hwnd() as _);
     }
 
+    #[cfg(target_os = "macos")]
+    {
+        menu_bar.init_for_nsapp();
+    }
+
     let menu_channel = menu_event_receiver();
     let mut open_item_disabled = false;
     let mut counter = 0;

src/lib.rs

@@ -123,6 +123,10 @@ impl Menu {
     /// ## Safety:
     ///
     /// This should be called before anything is added to the window.
+    ///
+    /// ## Panics:
+    ///
+    /// Panics if the gtk event loop hasn't been initialized on the thread.
     #[cfg(target_os = "linux")]
     pub fn init_for_gtk_window<W>(&self, w: &W) -> std::rc::Rc<gtk::Box>
     where
@@ -168,11 +172,69 @@ impl Menu {
         self.0.haccel()
     }
 
-    /// Adds this menu to NSApp.
+    /// Removes this menu from a [`gtk::Window`]
+    ///
+    /// ## Panics:
+    ///
+    /// Panics if the window doesn't have a menu created by this crate.
+    #[cfg(target_os = "linux")]
+    pub fn remove_for_gtk_window<W>(&self, w: &W)
+    where
+        W: gtk::prelude::IsA<gtk::Container>,
+        W: gtk::prelude::IsA<gtk::Window>,
+    {
+        self.0.remove_for_gtk_window(w)
+    }
+
+    /// Removes this menu from a win32 window
+    #[cfg(target_os = "windows")]
+    pub fn remove_for_hwnd(&self, hwnd: isize) {
+        self.0.remove_for_hwnd(hwnd)
+    }
+
+    /// Hides this menu from a [`gtk::Window`]
+    #[cfg(target_os = "linux")]
+    pub fn hide_for_gtk_window<W>(&self, w: &W)
+    where
+        W: gtk::prelude::IsA<gtk::Container>,
+        W: gtk::prelude::IsA<gtk::Window>,
+    {
+        self.0.hide_for_gtk_window(w)
+    }
+
+    /// Hides this menu from a win32 window
+    #[cfg(target_os = "windows")]
+    pub fn hide_for_hwnd(&self, hwnd: isize) {
+        self.0.hide_for_hwnd(hwnd)
+    }
+
+    /// Shows this menu from a [`gtk::Window`]
+    #[cfg(target_os = "linux")]
+    pub fn show_for_gtk_window<W>(&self, w: &W)
+    where
+        W: gtk::prelude::IsA<gtk::Container>,
+        W: gtk::prelude::IsA<gtk::Window>,
+    {
+        self.0.show_for_gtk_window(w)
+    }
+
+    /// Shows this menu from a win32 window
+    #[cfg(target_os = "windows")]
+    pub fn show_for_hwnd(&self, hwnd: isize) {
+        self.0.show_for_hwnd(hwnd)
+    }
+
+    /// Adds this menu to an NSApp.
     #[cfg(target_os = "macos")]
     pub fn init_for_nsapp(&self) {
         self.0.init_for_nsapp()
     }
+
+    /// Removes this menu from an NSApp.
+    #[cfg(target_os = "macos")]
+    pub fn remove_for_nsapp(&self) {
+        self.0.remove_for_nsapp()
+    }
 }
 
 /// This is a submenu within another [`Submenu`] or [`Menu`].

src/platform_impl/linux/mod.rs

@@ -1,10 +1,9 @@
 mod accelerator;
 
 use crate::counter::Counter;
+use accelerator::{to_gtk_accelerator, to_gtk_menemenoic};
 use gtk::{prelude::*, Orientation};
-use std::{cell::RefCell, rc::Rc};
+use std::{cell::RefCell, collections::HashMap, rc::Rc};
-
-use self::accelerator::{to_gtk_accelerator, to_gtk_menemenoic};
 
 static COUNTER: Counter = Counter::new();
 
@@ -36,7 +35,7 @@ struct InnerMenu {
     // multiple times, and thus can't be used in multiple windows, entry
     // keeps a vector of a tuple of `gtk::MenuBar` and `gtk::Box`
     // and push to it every time `Menu::init_for_gtk_window` is called.
-    gtk_items: Vec<(gtk::MenuBar, Rc<gtk::Box>)>,
+    gtk_items: HashMap<isize, (Option<gtk::MenuBar>, Rc<gtk::Box>)>,
     accel_group: gtk::AccelGroup,
 }
 
@@ -47,7 +46,7 @@ impl Menu {
     pub fn new() -> Self {
         Self(Rc::new(RefCell::new(InnerMenu {
             entries: Vec::new(),
-            gtk_items: Vec::new(),
+            gtk_items: HashMap::new(),
             accel_group: gtk::AccelGroup::new(),
         })))
     }
@@ -74,21 +73,82 @@ impl Menu {
         W: IsA<gtk::Window>,
     {
         let mut inner = self.0.borrow_mut();
+
+        // This is the first time this method has been called on a window
+        if inner.gtk_items.get(&(w.as_ptr() as _)).is_none() {
             let menu_bar = gtk::MenuBar::new();
-        add_entries_to_menu(&menu_bar, &inner.entries, &inner.accel_group);
+            let vbox = gtk::Box::new(Orientation::Vertical, 0);
+            w.add(&vbox);
+            inner
+                .gtk_items
+                .insert(w.as_ptr() as _, (Some(menu_bar), Rc::new(vbox)));
+        }
+
+        if let Some((menu_bar, vbox)) = inner.gtk_items.get(&(w.as_ptr() as _)) {
+            // This is NOT the first time this method has been called on a window.
+            // So it already contains a `gtk::Box` but it doesn't have a `gtk::MenuBar`
+            // because it was probably removed using `Menu::remove_for_gtk_window`
+            // so we only need to create the menubar
+            if menu_bar.is_none() {
+                let vbox = Rc::clone(vbox);
+                inner
+                    .gtk_items
+                    .insert(w.as_ptr() as _, (Some(gtk::MenuBar::new()), vbox));
+            }
+        }
+
+        let (menu_bar, vbox) = inner.gtk_items.get(&(w.as_ptr() as _)).unwrap();
+
+        add_entries_to_menu(
+            menu_bar.as_ref().unwrap(),
+            &inner.entries,
+            &inner.accel_group,
+        );
         w.add_accel_group(&inner.accel_group);
 
-        let vbox = gtk::Box::new(Orientation::Vertical, 0);
+        vbox.pack_start(menu_bar.as_ref().unwrap(), false, false, 0);
-        vbox.pack_start(&menu_bar, false, false, 0);
-        w.add(&vbox);
         vbox.show_all();
 
-        let vbox = Rc::new(vbox);
+        Rc::clone(vbox)
-        let vbox_c = Rc::clone(&vbox);
+    }
 
-        inner.gtk_items.push((menu_bar, vbox));
+    pub fn remove_for_gtk_window<W>(&self, w: &W)
+    where
+        W: IsA<gtk::Container>,
+        W: IsA<gtk::Window>,
+    {
+        let mut inner = self.0.borrow_mut();
 
-        vbox_c
+        if let Some((menu_bar, vbox)) = inner.gtk_items.get(&(w.as_ptr() as _)) {
+            vbox.remove(menu_bar.as_ref().unwrap());
+            w.remove_accel_group(&inner.accel_group);
+            let vbox = Rc::clone(vbox);
+            inner.gtk_items.insert(w.as_ptr() as _, (None, vbox));
+        }
+    }
+
+    pub fn hide_for_gtk_window<W>(&self, w: &W)
+    where
+        W: IsA<gtk::Container>,
+        W: IsA<gtk::Window>,
+    {
+        if let Some((menu_bar, _)) = self.0.borrow().gtk_items.get(&(w.as_ptr() as isize)) {
+            if let Some(menu_bar) = menu_bar {
+                menu_bar.hide();
+            }
+        }
+    }
+
+    pub fn show_for_gtk_window<W>(&self, w: &W)
+    where
+        W: IsA<gtk::Container>,
+        W: IsA<gtk::Window>,
+    {
+        if let Some((menu_bar, _)) = self.0.borrow().gtk_items.get(&(w.as_ptr() as isize)) {
+            if let Some(menu_bar) = menu_bar {
+                menu_bar.show_all();
+            }
+        }
     }
 }
 

src/platform_impl/macos/mod.rs

@@ -41,6 +41,12 @@ impl Menu {
             NSApp().setMainMenu_(self.0);
         }
     }
+
+    pub fn remove_for_nsapp(&self) {
+        unsafe {
+            NSApp().setMainMenu_(std::ptr::null_mut());
+        }
+    }
 }
 
 #[derive(Debug, Clone)]

src/platform_impl/windows/mod.rs

@@ -9,7 +9,7 @@ use util::{decode_wide, encode_wide, LOWORD};
 use windows_sys::Win32::{
     Foundation::{HWND, LPARAM, LRESULT, WPARAM},
     UI::{
-        Shell::{DefSubclassProc, SetWindowSubclass},
+        Shell::{DefSubclassProc, RemoveWindowSubclass, SetWindowSubclass},
         WindowsAndMessaging::{
             AppendMenuW, CreateAcceleratorTableW, CreateMenu, EnableMenuItem, GetMenuItemInfoW,
             SetMenu, SetMenuItemInfoW, ACCEL, HACCEL, HMENU, MENUITEMINFOW, MFS_DISABLED,
@@ -21,6 +21,7 @@ use windows_sys::Win32::{
 use self::accelerator::parse_accelerator;
 
 static COUNTER: Counter = Counter::new_with_start(563);
+const MENU_SUBCLASS_ID: usize = 232;
 
 struct InnerMenu {
     hmenu: HMENU,
@@ -64,7 +65,7 @@ impl Menu {
     pub fn init_for_hwnd(&self, hwnd: isize) {
         unsafe {
             SetMenu(hwnd, self.0.borrow().hmenu);
-            SetWindowSubclass(hwnd, Some(menu_subclass_proc), 22, 0);
+            SetWindowSubclass(hwnd, Some(menu_subclass_proc), MENU_SUBCLASS_ID, 0);
         };
     }
 
@@ -78,6 +79,25 @@ impl Menu {
             CreateAcceleratorTableW(inner.accelerators.as_ptr(), inner.accelerators.len() as _)
         };
     }
+
+    pub fn remove_for_hwnd(&self, hwnd: isize) {
+        unsafe {
+            RemoveWindowSubclass(hwnd, Some(menu_subclass_proc), MENU_SUBCLASS_ID);
+            SetMenu(hwnd, 0);
+        }
+    }
+
+    pub fn hide_for_hwnd(&self, hwnd: isize) {
+        unsafe {
+            SetMenu(hwnd, 0);
+        }
+    }
+
+    pub fn show_for_hwnd(&self, hwnd: isize) {
+        unsafe {
+            SetMenu(hwnd, self.0.borrow().hmenu);
+        }
+    }
 }
 
 #[derive(Clone)]