On macOS, add tabbing APIs

This should let the users control macOS tabbing and allow to create
windows in tab.

Co-authored-by: Amr Bashir <amr.bashir2015@gmail.com>

src/platform_impl/macos/appkit/mod.rs

@@ -24,6 +24,7 @@ mod menu_item;
 mod pasteboard;
 mod responder;
 mod screen;
+mod tab_group;
 mod text_input_context;
 mod version;
 mod view;
@@ -49,6 +50,7 @@ pub(crate) use self::pasteboard::{NSFilenamesPboardType, NSPasteboard, NSPastebo
 pub(crate) use self::responder::NSResponder;
 #[allow(unused_imports)]
 pub(crate) use self::screen::{NSDeviceDescriptionKey, NSScreen};
+pub(crate) use self::tab_group::NSWindowTabGroup;
 pub(crate) use self::text_input_context::NSTextInputContext;
 pub(crate) use self::version::NSAppKitVersion;
 pub(crate) use self::view::{NSTrackingRectTag, NSView};

src/platform_impl/macos/appkit/tab_group.rs

@@ -0,0 +1,28 @@
+use objc2::foundation::{NSArray, NSObject};
+use objc2::rc::{Id, Shared};
+use objc2::{extern_class, extern_methods, msg_send_id, ClassType};
+
+use super::NSWindow;
+
+extern_class!(
+    #[derive(Debug, PartialEq, Eq, Hash)]
+    pub(crate) struct NSWindowTabGroup;
+
+    unsafe impl ClassType for NSWindowTabGroup {
+        type Super = NSObject;
+    }
+);
+
+extern_methods!(
+    unsafe impl NSWindowTabGroup {
+        #[sel(selectNextTab)]
+        pub fn selectNextTab(&self);
+        #[sel(selectPreviousTab)]
+        pub fn selectPreviousTab(&self);
+        pub fn tabbedWindows(&self) -> Id<NSArray<NSWindow, Shared>, Shared> {
+            unsafe { msg_send_id![self, windows] }
+        }
+        #[sel(setSelectedWindow:)]
+        pub fn setSelectedWindow(&self, window: &NSWindow);
+    }
+);

src/platform_impl/macos/appkit/window.rs

@@ -6,7 +6,9 @@ use objc2::rc::{Id, Shared};
 use objc2::runtime::Object;
 use objc2::{extern_class, extern_methods, msg_send_id, ClassType};
 
-use super::{NSButton, NSColor, NSEvent, NSPasteboardType, NSResponder, NSScreen, NSView};
+use super::{
+    NSButton, NSColor, NSEvent, NSPasteboardType, NSResponder, NSScreen, NSView, NSWindowTabGroup,
+};
 
 extern_class!(
     /// Main-Thread-Only!
@@ -171,6 +173,12 @@ extern_methods!(
         #[sel(setLevel:)]
         pub fn setLevel(&self, level: NSWindowLevel);
 
+        #[sel(setAllowsAutomaticWindowTabbing:)]
+        pub fn setAllowsAutomaticWindowTabbing(val: bool);
+
+        #[sel(setTabbingIdentifier:)]
+        pub fn setTabbingIdentifier(&self, identifier: &NSString);
+
         #[sel(setDocumentEdited:)]
         pub fn setDocumentEdited(&self, val: bool);
 
@@ -201,6 +209,20 @@ extern_methods!(
         #[sel(isZoomed)]
         pub fn isZoomed(&self) -> bool;
 
+        #[sel(allowsAutomaticWindowTabbing)]
+        pub fn allowsAutomaticWindowTabbing() -> bool;
+
+        #[sel(selectNextTab)]
+        pub fn selectNextTab(&self);
+
+        pub fn tabbingIdentifier(&self) -> Id<NSString, Shared> {
+            unsafe { msg_send_id![self, tabbingIdentifier] }
+        }
+
+        pub fn tabGroup(&self) -> Id<NSWindowTabGroup, Shared> {
+            unsafe { msg_send_id![self, tabGroup] }
+        }
+
         #[sel(isDocumentEdited)]
         pub fn isDocumentEdited(&self) -> bool;
 

src/platform_impl/macos/window.rs

@@ -2,6 +2,7 @@
 
 use std::collections::VecDeque;
 use std::f64;
+use std::num::NonZeroUsize;
 use std::ops;
 use std::os::raw::c_void;
 use std::ptr::NonNull;
@@ -82,6 +83,8 @@ pub struct PlatformSpecificWindowBuilderAttributes {
     pub disallow_hidpi: bool,
     pub has_shadow: bool,
     pub accepts_first_mouse: bool,
+    pub allows_automatic_window_tabbing: bool,
+    pub tabbing_identifier: Option<String>,
     pub option_as_alt: OptionAsAlt,
 }
 
@@ -98,6 +101,8 @@ impl Default for PlatformSpecificWindowBuilderAttributes {
             disallow_hidpi: false,
             has_shadow: true,
             accepts_first_mouse: true,
+            allows_automatic_window_tabbing: true,
+            tabbing_identifier: None,
             option_as_alt: Default::default(),
         }
     }
@@ -357,6 +362,12 @@ impl WinitWindow {
             this.setTitle(&NSString::from_str(&attrs.title));
             this.setAcceptsMouseMovedEvents(true);
 
+            if let Some(identifier) = pl_attrs.tabbing_identifier {
+                this.setTabbingIdentifier(&NSString::from_str(&identifier));
+            }
+
+            NSWindow::setAllowsAutomaticWindowTabbing(pl_attrs.allows_automatic_window_tabbing);
+
             if attrs.content_protected {
                 this.setSharingType(NSWindowSharingType::NSWindowSharingNone);
             }
@@ -1394,6 +1405,46 @@ impl WindowExtMacOS for WinitWindow {
         self.setHasShadow(has_shadow)
     }
 
+    #[inline]
+    fn set_allows_automatic_window_tabbing(&self, enabled: bool) {
+        NSWindow::setAllowsAutomaticWindowTabbing(enabled);
+    }
+
+    #[inline]
+    fn allows_automatic_window_tabbing(&self) -> bool {
+        NSWindow::allowsAutomaticWindowTabbing()
+    }
+
+    #[inline]
+    fn set_tabbing_identifier(&self, identifier: &str) {
+        self.setTabbingIdentifier(&NSString::from_str(identifier))
+    }
+
+    #[inline]
+    fn tabbing_identifier(&self) -> String {
+        self.tabbingIdentifier().to_string()
+    }
+
+    #[inline]
+    fn select_next_tab(&self) {
+        self.tabGroup().selectNextTab();
+    }
+
+    #[inline]
+    fn select_previous_tab(&self) {
+        self.tabGroup().selectPreviousTab();
+    }
+
+    #[inline]
+    fn select_tab_at_index(&self, index: NonZeroUsize) {
+        let tab_group = self.tabGroup();
+        let windows = tab_group.tabbedWindows();
+        let index = index.get() - 1;
+        if index < windows.len() {
+            tab_group.setSelectedWindow(&windows[index]);
+        }
+    }
+
     fn is_document_edited(&self) -> bool {
         self.isDocumentEdited()
     }