macOS: Implement NSTextInputClient (#518)

Fixes #263

CHANGELOG.md

@@ -13,6 +13,9 @@
 - On macOS, `Window::get_current_monitor` now returns accurate values.
 - Added `WindowBuilderExt::with_resize_increments` to macOS.
 - **Breaking:** On X11, `WindowBuilderExt::with_resize_increments` and `WindowBuilderExt::with_base_size` now take `u32` values rather than `i32`.
+- macOS keyboard handling has been overhauled, allowing for the use of dead keys, IME, etc. Right modifier keys are also no longer reported as being left.
+- Added the `Window::set_ime_spot(x: i32, y: i32)` method, which is implemented on X11 and macOS.
+- **Breaking**: `os::unix::WindowExt::send_xim_spot(x: i16, y: i16)` no longer exists. Switch to the new `Window::set_ime_spot(x: i32, y: i32)`, which has equivalent functionality.
 
 # Version 0.14.0 (2018-05-09)
 

src/lib.rs

@@ -80,7 +80,6 @@
 //! to create an OpenGL/Vulkan/DirectX/Metal/etc. context that will draw on the window.
 //!
 
-#[cfg(any(target_os = "linux", target_os = "dragonfly", target_os = "freebsd", target_os = "openbsd", target_os = "windows"))]
 #[macro_use]
 extern crate lazy_static;
 extern crate libc;

src/os/unix.rs

@@ -94,8 +94,6 @@ pub trait WindowExt {
 
     fn get_xlib_xconnection(&self) -> Option<Arc<XConnection>>;
 
-    fn send_xim_spot(&self, x: i16, y: i16);
-
     /// This function returns the underlying `xcb_connection_t` of an xlib `Display`.
     ///
     /// Returns `None` if the window doesn't use xlib (if it uses wayland for example).
@@ -165,12 +163,6 @@ impl WindowExt for Window {
         }
     }
 
-    fn send_xim_spot(&self, x: i16, y: i16) {
-        if let LinuxWindow::X(ref w) = self.window {
-            w.send_xim_spot(x, y);
-        }
-    }
-
     #[inline]
     fn get_wayland_surface(&self) -> Option<*mut raw::c_void> {
         match self.window {

src/platform/android/mod.rs

@@ -328,6 +328,11 @@ impl Window {
         // N/A
     }
 
+    #[inline]
+    pub fn set_ime_spot(&self, _x: i32, _y: i32) {
+        // N/A
+    }
+
     #[inline]
     pub fn get_current_monitor(&self) -> RootMonitorId {
         RootMonitorId{inner: MonitorId}

src/platform/emscripten/mod.rs

@@ -548,6 +548,11 @@ impl Window {
         // N/A
     }
 
+    #[inline]
+    pub fn set_ime_spot(&self, _x: i32, _y: i32) {
+        // N/A
+    }
+
     #[inline]
     pub fn get_current_monitor(&self) -> ::MonitorId {
         ::MonitorId{inner: MonitorId}

src/platform/ios/mod.rs

@@ -375,6 +375,11 @@ impl Window {
         // N/A
     }
 
+    #[inline]
+    pub fn set_ime_spot(&self, _x: i32, _y: i32) {
+        // N/A
+    }
+
     #[inline]
     pub fn get_current_monitor(&self) -> RootMonitorId {
         RootMonitorId{inner: MonitorId}

src/platform/linux/mod.rs

@@ -310,6 +310,14 @@ impl Window {
         }
     }
 
+    #[inline]
+    pub fn set_ime_spot(&self, x: i32, y: i32) {
+        match self {
+            &Window::X(ref w) => w.send_xim_spot(x as i16, y as i16),
+            &Window::Wayland(_) => (),
+        }
+    }
+
     #[inline]
     pub fn get_current_monitor(&self) -> RootMonitorId {
         match self {

src/platform/macos/events_loop.rs

@@ -6,6 +6,7 @@ use std::collections::VecDeque;
 use std::sync::{Arc, Mutex, Weak};
 use super::window::Window2;
 use std;
+use std::os::raw::*;
 use super::DeviceId;
 
 
@@ -315,127 +316,50 @@ impl EventsLoop {
             });
 
         match event_type {
-
-            appkit::NSKeyDown => {
-                let mut events = std::collections::VecDeque::new();
-                let received_c_str = foundation::NSString::UTF8String(ns_event.characters());
-                let received_str = std::ffi::CStr::from_ptr(received_c_str);
-
-                let vkey =  to_virtual_key_code(NSEvent::keyCode(ns_event));
-                let state = ElementState::Pressed;
-                let code = NSEvent::keyCode(ns_event) as u32;
-                let window_event = WindowEvent::KeyboardInput {
-                    device_id: DEVICE_ID,
-                    input: KeyboardInput {
-                        state: state,
-                        scancode: code,
-                        virtual_keycode: vkey,
-                        modifiers: event_mods(ns_event),
-                    },
-                };
-                for received_char in std::str::from_utf8(received_str.to_bytes()).unwrap().chars() {
-                    let window_event = WindowEvent::ReceivedCharacter(received_char);
-                    events.push_back(into_event(window_event));
-                }
-                self.shared.pending_events.lock().unwrap().extend(events.into_iter());
-                Some(into_event(window_event))
-            },
-
-            appkit::NSKeyUp => {
-                let vkey =  to_virtual_key_code(NSEvent::keyCode(ns_event));
-
-                let state = ElementState::Released;
-                let code = NSEvent::keyCode(ns_event) as u32;
-                let window_event = WindowEvent::KeyboardInput {
-                    device_id: DEVICE_ID,
-                    input: KeyboardInput {
-                        state: state,
-                        scancode: code,
-                        virtual_keycode: vkey,
-                        modifiers: event_mods(ns_event),
-                    },
-                };
-                Some(into_event(window_event))
-            },
-
             appkit::NSFlagsChanged => {
-                unsafe fn modifier_event(event: cocoa::base::id,
-                                         keymask: NSEventModifierFlags,
-                                         key: events::VirtualKeyCode,
-                                         key_pressed: bool) -> Option<WindowEvent>
-                {
-                    if !key_pressed && NSEvent::modifierFlags(event).contains(keymask) {
-                        let state = ElementState::Pressed;
-                        let code = NSEvent::keyCode(event) as u32;
-                        let window_event = WindowEvent::KeyboardInput {
-                            device_id: DEVICE_ID,
-                            input: KeyboardInput {
-                                state: state,
-                                scancode: code,
-                                virtual_keycode: Some(key),
-                                modifiers: event_mods(event),
-                            },
-                        };
-                        Some(window_event)
-
-                    } else if key_pressed && !NSEvent::modifierFlags(event).contains(keymask) {
-                        let state = ElementState::Released;
-                        let code = NSEvent::keyCode(event) as u32;
-                        let window_event = WindowEvent::KeyboardInput {
-                            device_id: DEVICE_ID,
-                            input: KeyboardInput {
-                                state: state,
-                                scancode: code,
-                                virtual_keycode: Some(key),
-                                modifiers: event_mods(event),
-                            },
-                        };
-                        Some(window_event)
-
-                    } else {
-                        None
-                    }
-                }
-
                 let mut events = std::collections::VecDeque::new();
-                if let Some(window_event) = modifier_event(ns_event,
+
+                if let Some(window_event) = modifier_event(
+                    ns_event,
                     NSEventModifierFlags::NSShiftKeyMask,
-                                                           events::VirtualKeyCode::LShift,
-                                                           self.modifiers.shift_pressed)
-                {
+                    self.modifiers.shift_pressed,
+                ) {
                     self.modifiers.shift_pressed = !self.modifiers.shift_pressed;
                     events.push_back(into_event(window_event));
                 }
 
-                if let Some(window_event) = modifier_event(ns_event,
+                if let Some(window_event) = modifier_event(
+                    ns_event,
                     NSEventModifierFlags::NSControlKeyMask,
-                                                           events::VirtualKeyCode::LControl,
-                                                           self.modifiers.ctrl_pressed)
-                {
+                    self.modifiers.ctrl_pressed,
+                ) {
                     self.modifiers.ctrl_pressed = !self.modifiers.ctrl_pressed;
                     events.push_back(into_event(window_event));
                 }
 
-                if let Some(window_event) = modifier_event(ns_event,
+                if let Some(window_event) = modifier_event(
+                    ns_event,
                     NSEventModifierFlags::NSCommandKeyMask,
-                                                           events::VirtualKeyCode::LWin,
-                                                           self.modifiers.win_pressed)
-                {
+                    self.modifiers.win_pressed,
+                ) {
                     self.modifiers.win_pressed = !self.modifiers.win_pressed;
                     events.push_back(into_event(window_event));
                 }
 
-                if let Some(window_event) = modifier_event(ns_event,
+                if let Some(window_event) = modifier_event(
+                    ns_event,
                     NSEventModifierFlags::NSAlternateKeyMask,
-                                                           events::VirtualKeyCode::LAlt,
-                                                           self.modifiers.alt_pressed)
-                {
+                    self.modifiers.alt_pressed,
+                ) {
                     self.modifiers.alt_pressed = !self.modifiers.alt_pressed;
                     events.push_back(into_event(window_event));
                 }
 
                 let event = events.pop_front();
-                self.shared.pending_events.lock().unwrap().extend(events.into_iter());
+                self.shared.pending_events
+                    .lock()
+                    .unwrap()
+                    .extend(events.into_iter());
                 event
             },
 
@@ -618,8 +542,7 @@ impl Proxy {
     }
 }
 
-
-fn to_virtual_key_code(code: u16) -> Option<events::VirtualKeyCode> {
+pub fn to_virtual_key_code(code: c_ushort) -> Option<events::VirtualKeyCode> {
     Some(match code {
         0x00 => events::VirtualKeyCode::A,
         0x01 => events::VirtualKeyCode::S,
@@ -755,7 +678,7 @@ fn to_virtual_key_code(code: u16) -> Option<events::VirtualKeyCode> {
     })
 }
 
-fn event_mods(event: cocoa::base::id) -> ModifiersState {
+pub fn event_mods(event: cocoa::base::id) -> ModifiersState {
     let flags = unsafe {
         NSEvent::modifierFlags(event)
     };
@@ -767,5 +690,30 @@ fn event_mods(event: cocoa::base::id) -> ModifiersState {
     }
 }
 
+unsafe fn modifier_event(
+    ns_event: cocoa::base::id,
+    keymask: NSEventModifierFlags,
+    key_pressed: bool,
+) -> Option<WindowEvent> {
+    if !key_pressed && NSEvent::modifierFlags(ns_event).contains(keymask) 
+    || key_pressed && !NSEvent::modifierFlags(ns_event).contains(keymask) {
+        let state = ElementState::Released;
+        let keycode = NSEvent::keyCode(ns_event);
+        let scancode = keycode as u32;
+        let virtual_keycode = to_virtual_key_code(keycode);
+        Some(WindowEvent::KeyboardInput {
+            device_id: DEVICE_ID,
+            input: KeyboardInput {
+                state,
+                scancode,
+                virtual_keycode,
+                modifiers: event_mods(ns_event),
+            },
+        })
+    } else {
+        None
+    }
+}
+
 // Constant device ID, to be removed when this backend is updated to report real device IDs.
-const DEVICE_ID: ::DeviceId = ::DeviceId(DeviceId);
+pub const DEVICE_ID: ::DeviceId = ::DeviceId(DeviceId);

src/platform/macos/ffi.rs

@@ -0,0 +1,74 @@
+// TODO: Upstream these
+
+#![allow(non_snake_case, non_upper_case_globals)]
+
+use cocoa::base::{class, id};
+use cocoa::foundation::{NSInteger, NSUInteger};
+use objc;
+
+pub const NSNotFound: NSInteger = NSInteger::max_value();
+
+#[repr(C)]
+pub struct NSRange {
+    pub location: NSUInteger,
+    pub length: NSUInteger,
+}
+
+impl NSRange {
+    #[inline]
+    pub fn new(location: NSUInteger, length: NSUInteger) -> NSRange {
+        NSRange { location, length }
+    }
+}
+
+unsafe impl objc::Encode for NSRange {
+    fn encode() -> objc::Encoding {
+        let encoding = format!(
+            // TODO: Verify that this is correct
+            "{{NSRange={}{}}}",
+            NSUInteger::encode().as_str(),
+            NSUInteger::encode().as_str(),
+        );
+        unsafe { objc::Encoding::from_str(&encoding) }
+    }
+}
+
+pub trait NSMutableAttributedString: Sized {
+    unsafe fn alloc(_: Self) -> id {
+        msg_send![class("NSMutableAttributedString"), alloc]
+    }
+
+    unsafe fn init(self) -> id; // *mut NSMutableAttributedString
+    unsafe fn initWithString(self, string: id) -> id;
+    unsafe fn initWithAttributedString(self, string: id) -> id;
+
+    unsafe fn string(self) -> id; // *mut NSString
+    unsafe fn mutableString(self) -> id; // *mut NSMutableString
+    unsafe fn length(self) -> NSUInteger;
+}
+
+impl NSMutableAttributedString for id {
+    unsafe fn init(self) -> id {
+        msg_send![self, init]
+    }
+
+    unsafe fn initWithString(self, string: id) -> id {
+        msg_send![self, initWithString:string]
+    }
+
+    unsafe fn initWithAttributedString(self, string: id) -> id {
+        msg_send![self, initWithAttributedString:string]
+    }
+
+    unsafe fn string(self) -> id {
+        msg_send![self, string]
+    }
+
+    unsafe fn mutableString(self) -> id {
+        msg_send![self, mutableString]
+    }
+
+    unsafe fn length(self) -> NSUInteger {
+        msg_send![self, length]
+    }
+}

src/platform/macos/mod.rs

@@ -38,5 +38,8 @@ impl Window {
 }
 
 mod events_loop;
+mod ffi;
 mod monitor;
+mod util;
+mod view;
 mod window;

src/platform/macos/util.rs

@@ -0,0 +1,38 @@
+use cocoa::appkit::NSWindowStyleMask;
+use cocoa::base::{class, id, nil};
+use cocoa::foundation::{NSRect, NSUInteger};
+use core_graphics::display::CGDisplay;
+
+use platform::platform::ffi;
+use platform::platform::window::IdRef;
+
+pub const EMPTY_RANGE: ffi::NSRange = ffi::NSRange {
+    location: ffi::NSNotFound as NSUInteger,
+    length: 0,
+};
+
+// For consistency with other platforms, this will...
+// 1. translate the bottom-left window corner into the top-left window corner
+// 2. translate the coordinate from a bottom-left origin coordinate system to a top-left one
+pub fn bottom_left_to_top_left(rect: NSRect) -> i32 {
+    (CGDisplay::main().pixels_high() as f64 - (rect.origin.y + rect.size.height)) as _
+}
+
+pub unsafe fn set_style_mask(window: id, view: id, mask: NSWindowStyleMask) {
+    use cocoa::appkit::NSWindow;
+    window.setStyleMask_(mask);
+    // If we don't do this, key handling will break. Therefore, never call `setStyleMask` directly!
+    window.makeFirstResponder_(view);
+}
+
+pub unsafe fn create_input_context(view: id) -> IdRef {
+    let input_context: id = msg_send![class("NSTextInputContext"), alloc];
+    let input_context: id = msg_send![input_context, initWithClient:view];
+    IdRef::new(input_context)
+}
+
+#[allow(dead_code)]
+pub unsafe fn open_emoji_picker() {
+    let app: id = msg_send![class("NSApplication"), sharedApplication];
+    let _: () = msg_send![app, orderFrontCharacterPalette:nil];
+}

src/platform/macos/view.rs

@@ -0,0 +1,411 @@
+// This is a pretty close port of the implementation in GLFW:
+// https://github.com/glfw/glfw/blob/7ef34eb06de54dd9186d3d21a401b2ef819b59e7/src/cocoa_window.m
+
+use std::{slice, str};
+use std::boxed::Box;
+use std::collections::VecDeque;
+use std::os::raw::*;
+use std::sync::Weak;
+
+use cocoa::base::{class, id, nil};
+use cocoa::appkit::NSWindow;
+use cocoa::foundation::{NSPoint, NSRect, NSSize, NSString, NSUInteger};
+use objc::declare::ClassDecl;
+use objc::runtime::{Class, Object, Protocol, Sel, BOOL};
+
+use {ElementState, Event, KeyboardInput, WindowEvent, WindowId};
+use platform::platform::events_loop::{DEVICE_ID, event_mods, Shared, to_virtual_key_code};
+use platform::platform::util;
+use platform::platform::ffi::*;
+use platform::platform::window::{get_window_id, IdRef};
+
+struct ViewState {
+    window: id,
+    shared: Weak<Shared>,
+    ime_spot: Option<(i32, i32)>,
+    raw_characters: Option<String>,
+}
+
+pub fn new_view(window: id, shared: Weak<Shared>) -> IdRef {
+    let state = ViewState { window, shared, ime_spot: None, raw_characters: None };
+    unsafe {
+        // This is free'd in `dealloc`
+        let state_ptr = Box::into_raw(Box::new(state)) as *mut c_void;
+        let view: id = msg_send![VIEW_CLASS.0, alloc];
+        IdRef::new(msg_send![view, initWithWinit:state_ptr])
+    }
+}
+
+pub fn set_ime_spot(view: id, input_context: id, x: i32, y: i32) {
+    unsafe {
+        let state_ptr: *mut c_void = *(*view).get_mut_ivar("winitState");
+        let state = &mut *(state_ptr as *mut ViewState);
+        let content_rect = NSWindow::contentRectForFrameRect_(
+            state.window,
+            NSWindow::frame(state.window),
+        );
+        let base_x = content_rect.origin.x as i32;
+        let base_y = (content_rect.origin.y + content_rect.size.height) as i32;
+        state.ime_spot = Some((base_x + x, base_y - y));
+        let _: () = msg_send![input_context, invalidateCharacterCoordinates];
+    }
+}
+
+struct ViewClass(*const Class);
+unsafe impl Send for ViewClass {}
+unsafe impl Sync for ViewClass {}
+
+lazy_static! {
+    static ref VIEW_CLASS: ViewClass = unsafe {
+        let superclass = Class::get("NSView").unwrap();
+        let mut decl = ClassDecl::new("WinitView", superclass).unwrap();
+        decl.add_method(sel!(dealloc), dealloc as extern fn(&Object, Sel));
+        decl.add_method(
+            sel!(initWithWinit:),
+            init_with_winit as extern fn(&Object, Sel, *mut c_void) -> id,
+        );
+        decl.add_method(sel!(hasMarkedText), has_marked_text as extern fn(&Object, Sel) -> BOOL);
+        decl.add_method(
+            sel!(markedRange),
+            marked_range as extern fn(&Object, Sel) -> NSRange,
+        );
+        decl.add_method(sel!(selectedRange), selected_range as extern fn(&Object, Sel) -> NSRange);
+        decl.add_method(
+            sel!(setMarkedText:selectedRange:replacementRange:),
+            set_marked_text as extern fn(&mut Object, Sel, id, NSRange, NSRange),
+        );
+        decl.add_method(sel!(unmarkText), unmark_text as extern fn(&Object, Sel));
+        decl.add_method(
+            sel!(validAttributesForMarkedText),
+            valid_attributes_for_marked_text as extern fn(&Object, Sel) -> id,
+        );
+        decl.add_method(
+            sel!(attributedSubstringForProposedRange:actualRange:),
+            attributed_substring_for_proposed_range
+                as extern fn(&Object, Sel, NSRange, *mut c_void) -> id,
+        );
+        decl.add_method(
+            sel!(insertText:replacementRange:),
+            insert_text as extern fn(&Object, Sel, id, NSRange),
+        );
+        decl.add_method(
+            sel!(characterIndexForPoint:),
+            character_index_for_point as extern fn(&Object, Sel, NSPoint) -> NSUInteger,
+        );
+        decl.add_method(
+            sel!(firstRectForCharacterRange:actualRange:),
+            first_rect_for_character_range
+                as extern fn(&Object, Sel, NSRange, *mut c_void) -> NSRect,
+        );
+        decl.add_method(
+            sel!(doCommandBySelector:),
+            do_command_by_selector as extern fn(&Object, Sel, Sel),
+        );
+        decl.add_method(sel!(keyDown:), key_down as extern fn(&Object, Sel, id));
+        decl.add_method(sel!(keyUp:), key_up as extern fn(&Object, Sel, id));
+        decl.add_method(sel!(insertTab:), insert_tab as extern fn(&Object, Sel, id));
+        decl.add_method(sel!(insertBackTab:), insert_back_tab as extern fn(&Object, Sel, id));
+        decl.add_ivar::<*mut c_void>("winitState");
+        decl.add_ivar::<id>("markedText");
+        let protocol = Protocol::get("NSTextInputClient").unwrap();
+        decl.add_protocol(&protocol);
+        ViewClass(decl.register())
+    };
+}
+
+extern fn dealloc(this: &Object, _sel: Sel) {
+    unsafe {
+        let state: *mut c_void = *this.get_ivar("winitState");
+        let marked_text: id = *this.get_ivar("markedText");
+        let _: () = msg_send![marked_text, release];
+        Box::from_raw(state as *mut ViewState);
+    }
+}
+
+extern fn init_with_winit(this: &Object, _sel: Sel, state: *mut c_void) -> id {
+    unsafe {
+        let this: id = msg_send![this, init];
+        if this != nil {
+            (*this).set_ivar("winitState", state);
+            let marked_text = <id as NSMutableAttributedString>::init(
+                NSMutableAttributedString::alloc(nil),
+            );
+            (*this).set_ivar("markedText", marked_text);
+        }
+        this
+    }
+}
+
+extern fn has_marked_text(this: &Object, _sel: Sel) -> BOOL {
+    unsafe {
+        let marked_text: id = *this.get_ivar("markedText");
+        (marked_text.length() > 0) as i8
+    }
+}
+
+extern fn marked_range(this: &Object, _sel: Sel) -> NSRange {
+    unsafe {
+        let marked_text: id = *this.get_ivar("markedText");
+        let length = marked_text.length();
+        if length > 0 {
+            NSRange::new(0, length - 1)
+        } else {
+            util::EMPTY_RANGE
+        }
+    }
+}
+
+extern fn selected_range(_this: &Object, _sel: Sel) -> NSRange {
+    util::EMPTY_RANGE
+}
+
+extern fn set_marked_text(
+    this: &mut Object,
+    _sel: Sel,
+    string: id,
+    _selected_range: NSRange,
+    _replacement_range: NSRange,
+) {
+    unsafe {
+        let marked_text_ref: &mut id = this.get_mut_ivar("markedText");
+        let _: () = msg_send![(*marked_text_ref), release];
+        let marked_text = NSMutableAttributedString::alloc(nil);
+        let has_attr = msg_send![string, isKindOfClass:class("NSAttributedString")];
+        if has_attr {
+            marked_text.initWithAttributedString(string);
+        } else {
+            marked_text.initWithString(string);
+        };
+        *marked_text_ref = marked_text;
+    }
+}
+
+extern fn unmark_text(this: &Object, _sel: Sel) {
+    unsafe {
+        let marked_text: id = *this.get_ivar("markedText");
+        let mutable_string = marked_text.mutableString();
+        let _: () = msg_send![mutable_string, setString:""];
+        let input_context: id = msg_send![this, inputContext];
+        let _: () = msg_send![input_context, discardMarkedText];
+    }
+}
+
+extern fn valid_attributes_for_marked_text(_this: &Object, _sel: Sel) -> id {
+    unsafe { msg_send![class("NSArray"), array] }
+}
+
+extern fn attributed_substring_for_proposed_range(
+    _this: &Object,
+    _sel: Sel,
+    _range: NSRange,
+    _actual_range: *mut c_void, // *mut NSRange
+) -> id {
+    nil
+}
+
+extern fn character_index_for_point(_this: &Object, _sel: Sel, _point: NSPoint) -> NSUInteger {
+    0
+}
+
+extern fn first_rect_for_character_range(
+    this: &Object,
+    _sel: Sel,
+    _range: NSRange,
+    _actual_range: *mut c_void, // *mut NSRange
+) -> NSRect {
+    unsafe {
+        let state_ptr: *mut c_void = *this.get_ivar("winitState");
+        let state = &mut *(state_ptr as *mut ViewState);
+        let (x, y) = state.ime_spot.unwrap_or_else(|| {
+            let content_rect = NSWindow::contentRectForFrameRect_(
+                state.window,
+                NSWindow::frame(state.window),
+            );
+            let x = content_rect.origin.x;
+            let y = util::bottom_left_to_top_left(content_rect);
+            (x as i32, y as i32)
+        });
+        
+        NSRect::new(
+            NSPoint::new(x as _, y as _),
+            NSSize::new(0.0, 0.0),
+        )
+    }
+}
+
+extern fn insert_text(this: &Object, _sel: Sel, string: id, _replacement_range: NSRange) {
+    unsafe {
+        let state_ptr: *mut c_void = *this.get_ivar("winitState");
+        let state = &mut *(state_ptr as *mut ViewState);
+
+        let has_attr = msg_send![string, isKindOfClass:class("NSAttributedString")];
+        let characters = if has_attr {
+            // This is a *mut NSAttributedString
+            msg_send![string, string]
+        } else {
+            // This is already a *mut NSString
+            string
+        };
+
+        let slice = slice::from_raw_parts(
+            characters.UTF8String() as *const c_uchar,
+            characters.len(),
+        );
+        let string = str::from_utf8_unchecked(slice);
+
+        // We don't need this now, but it's here if that changes.
+        //let event: id = msg_send![class("NSApp"), currentEvent];
+
+        let mut events = VecDeque::with_capacity(characters.len());
+        for character in string.chars() {
+            events.push_back(Event::WindowEvent {
+                window_id: WindowId(get_window_id(state.window)),
+                event: WindowEvent::ReceivedCharacter(character),
+            });
+        }
+
+        if let Some(shared) = state.shared.upgrade() {
+            shared.pending_events
+                .lock()
+                .unwrap()
+                .append(&mut events);
+        }
+    }
+}
+
+extern fn do_command_by_selector(this: &Object, _sel: Sel, command: Sel) {
+    // Basically, we're sent this message whenever a keyboard event that doesn't generate a "human readable" character
+    // happens, i.e. newlines, tabs, and Ctrl+C.
+    unsafe {
+        let state_ptr: *mut c_void = *this.get_ivar("winitState");
+        let state = &mut *(state_ptr as *mut ViewState);
+
+        let shared = if let Some(shared) = state.shared.upgrade() {
+            shared
+        } else {
+            return;
+        };
+
+        let mut events = VecDeque::with_capacity(1);
+        if command == sel!(insertNewline:) {
+            // The `else` condition would emit the same character, but I'm keeping this here both...
+            // 1) as a reminder for how `doCommandBySelector` works
+            // 2) to make the newline character explicit (...not that it matters)
+            events.push_back(Event::WindowEvent {
+                window_id: WindowId(get_window_id(state.window)),
+                event: WindowEvent::ReceivedCharacter('\n'),
+            });
+        } else {
+            let raw_characters = state.raw_characters.take();
+            if let Some(raw_characters) = raw_characters {
+                for character in raw_characters.chars() {
+                    events.push_back(Event::WindowEvent {
+                        window_id: WindowId(get_window_id(state.window)),
+                        event: WindowEvent::ReceivedCharacter(character),
+                    });
+                }
+            }
+        };
+
+        shared.pending_events
+            .lock()
+            .unwrap()
+            .append(&mut events);
+    }
+}
+
+extern fn key_down(this: &Object, _sel: Sel, event: id) {
+    unsafe {
+        let state_ptr: *mut c_void = *this.get_ivar("winitState");
+        let state = &mut *(state_ptr as *mut ViewState);
+
+        let keycode: c_ushort = msg_send![event, keyCode];
+        let virtual_keycode = to_virtual_key_code(keycode);
+        let scancode = keycode as u32;
+
+        let window_event = Event::WindowEvent {
+            window_id: WindowId(get_window_id(state.window)),
+            event: WindowEvent::KeyboardInput {
+                device_id: DEVICE_ID,
+                input: KeyboardInput {
+                    state: ElementState::Pressed,
+                    scancode,
+                    virtual_keycode,
+                    modifiers: event_mods(event),
+                },
+            },
+        };
+
+        state.raw_characters = {
+            let characters: id = msg_send![event, characters];
+            let slice = slice::from_raw_parts(
+                characters.UTF8String() as *const c_uchar,
+                characters.len(),
+            );
+            let string = str::from_utf8_unchecked(slice);
+            Some(string.to_owned())
+        };
+
+        if let Some(shared) = state.shared.upgrade() {
+            shared.pending_events
+                .lock()
+                .unwrap()
+                .push_back(window_event);
+        }
+
+        let array: id = msg_send![class("NSArray"), arrayWithObject:event];
+        let (): _ = msg_send![this, interpretKeyEvents:array];
+    }
+}
+
+extern fn key_up(this: &Object, _sel: Sel, event: id) {
+    unsafe {
+        let state_ptr: *mut c_void = *this.get_ivar("winitState");
+        let state = &mut *(state_ptr as *mut ViewState);
+
+        let keycode: c_ushort = msg_send![event, keyCode];
+        let virtual_keycode = to_virtual_key_code(keycode);
+        let scancode = keycode as u32;
+        let window_event = Event::WindowEvent {
+            window_id: WindowId(get_window_id(state.window)),
+            event: WindowEvent::KeyboardInput {
+                device_id: DEVICE_ID,
+                input: KeyboardInput {
+                    state: ElementState::Released,
+                    scancode,
+                    virtual_keycode,
+                    modifiers: event_mods(event),
+                },
+            },
+        };
+
+        if let Some(shared) = state.shared.upgrade() {
+            shared.pending_events
+                .lock()
+                .unwrap()
+                .push_back(window_event);
+        }
+    }
+}
+
+extern fn insert_tab(this: &Object, _sel: Sel, _sender: id) {
+    unsafe {
+        let window: id = msg_send![this, window];
+        let first_responder: id = msg_send![window, firstResponder];
+        let this_ptr = this as *const _ as *mut _;
+        if first_responder == this_ptr {
+            let (): _ = msg_send![window, selectNextKeyView:this];
+        }
+    }
+}
+
+extern fn insert_back_tab(this: &Object, _sel: Sel, _sender: id) {
+    unsafe {
+        let window: id = msg_send![this, window];
+        let first_responder: id = msg_send![window, firstResponder];
+        let this_ptr = this as *const _ as *mut _;
+        if first_responder == this_ptr {
+            let (): _ = msg_send![window, selectPreviousKeyView:this];
+        }
+    }
+}

src/platform/macos/window.rs

@@ -25,6 +25,8 @@ use std::sync::Weak;
 use std::cell::{Cell, RefCell};
 
 use super::events_loop::{EventsLoop, Shared};
+use platform::platform::util;
+use platform::platform::view::{new_view, set_ime_spot};
 
 use window::MonitorId as RootMonitorId;
 
@@ -56,15 +58,14 @@ impl DelegateState {
             let curr_mask = self.window.styleMask();
 
             if !curr_mask.contains(NSWindowStyleMask::NSTitledWindowMask) {
-                self.window
-                    .setStyleMask_(NSWindowStyleMask::NSResizableWindowMask);
+                util::set_style_mask(*self.window, *self.view, NSWindowStyleMask::NSResizableWindowMask);
             }
 
             let is_zoomed: BOOL = msg_send![*self.window, isZoomed];
 
             // Roll back temp styles
             if !curr_mask.contains(NSWindowStyleMask::NSTitledWindowMask) {
-                self.window.setStyleMask_(curr_mask);
+                util::set_style_mask(*self.window, *self.view, curr_mask);
             }
 
             is_zoomed != 0
@@ -79,7 +80,7 @@ impl DelegateState {
             let save_style_opt = self.save_style_mask.take();
 
             if let Some(save_style) = save_style_opt {
-                self.window.setStyleMask_(save_style);
+                util::set_style_mask(*self.window, *self.view, save_style);
             }
 
             win_attribs.maximized
@@ -167,7 +168,7 @@ impl WindowDelegate {
         unsafe fn emit_move_event(state: &mut DelegateState) {
             let frame_rect = NSWindow::frame(*state.window);
             let x = frame_rect.origin.x as _;
-            let y = Window2::bottom_left_to_top_left(frame_rect);
+            let y = util::bottom_left_to_top_left(frame_rect);
             let moved = state.previous_position != Some((x, y));
             if moved {
                 state.previous_position = Some((x, y));
@@ -495,6 +496,7 @@ pub struct Window2 {
     pub view: IdRef,
     pub window: IdRef,
     pub delegate: WindowDelegate,
+    pub input_context: IdRef,
 }
 
 unsafe impl Send for Window2 {}
@@ -582,7 +584,7 @@ impl Window2 {
                 return Err(OsError(format!("Couldn't create NSWindow")));
             },
         };
-        let view = match Window2::create_view(*window) {
+        let view = match Window2::create_view(*window, Weak::clone(&shared)) {
             Some(view) => view,
             None => {
                 let _: () = unsafe { msg_send![autoreleasepool, drain] };
@@ -590,6 +592,8 @@ impl Window2 {
             },
         };
 
+        let input_context = unsafe { util::create_input_context(*view) };
+
         unsafe {
             if win_attribs.transparent {
                 (*window as id).setOpaque_(NO);
@@ -628,6 +632,7 @@ impl Window2 {
             view: view,
             window: window,
             delegate: WindowDelegate::new(ds),
+            input_context,
         };
 
         // Set fullscreen mode after we setup everything
@@ -681,13 +686,10 @@ impl Window2 {
         static INIT: std::sync::Once = std::sync::ONCE_INIT;
 
         INIT.call_once(|| unsafe {
-            extern fn on_key_down(_this: &Object, _sel: Sel, _id: id) {}
-
             let window_superclass = Class::get("NSWindow").unwrap();
             let mut decl = ClassDecl::new("WinitWindow", window_superclass).unwrap();
             decl.add_method(sel!(canBecomeMainWindow), yes as extern fn(&Object, Sel) -> BOOL);
             decl.add_method(sel!(canBecomeKeyWindow), yes as extern fn(&Object, Sel) -> BOOL);
-            decl.add_method(sel!(keyDown:), on_key_down as extern fn(&Object, Sel, id));
             WINDOW2_CLASS = decl.register();
         });
 
@@ -788,12 +790,13 @@ impl Window2 {
         }
     }
 
-    fn create_view(window: id) -> Option<IdRef> {
+    fn create_view(window: id, shared: Weak<Shared>) -> Option<IdRef> {
         unsafe {
-            let view = IdRef::new(NSView::init(NSView::alloc(nil)));
+            let view = new_view(window, shared);
             view.non_nil().map(|view| {
                 view.setWantsBestResolutionOpenGLSurface_(YES);
                 window.setContentView_(*view);
+                window.makeFirstResponder_(*view);
                 view
             })
         }
@@ -816,18 +819,11 @@ impl Window2 {
         unsafe { NSWindow::orderOut_(*self.window, nil); }
     }
 
-    // For consistency with other platforms, this will...
-    // 1. translate the bottom-left window corner into the top-left window corner
-    // 2. translate the coordinate from a bottom-left origin coordinate system to a top-left one
-    fn bottom_left_to_top_left(rect: NSRect) -> i32 {
-        (CGDisplay::main().pixels_high() as f64 - (rect.origin.y + rect.size.height)) as _
-    }
-
     pub fn get_position(&self) -> Option<(i32, i32)> {
         let frame_rect = unsafe { NSWindow::frame(*self.window) };
         Some((
             frame_rect.origin.x as i32,
-            Self::bottom_left_to_top_left(frame_rect),
+            util::bottom_left_to_top_left(frame_rect),
         ))
     }
 
@@ -840,7 +836,7 @@ impl Window2 {
         };
         Some((
             content_rect.origin.x as i32,
-            Self::bottom_left_to_top_left(content_rect),
+            util::bottom_left_to_top_left(content_rect),
         ))
     }
 
@@ -1029,10 +1025,9 @@ impl Window2 {
                 let curr_mask = state.window.styleMask();
 
                 if !curr_mask.contains(NSWindowStyleMask::NSTitledWindowMask) {
-                    state.window.setStyleMask_(
-                        NSWindowStyleMask::NSTitledWindowMask
-                            | NSWindowStyleMask::NSResizableWindowMask,
-                    );
+                    let mask = NSWindowStyleMask::NSTitledWindowMask
+                        | NSWindowStyleMask::NSResizableWindowMask;
+                    util::set_style_mask(*self.window, *self.view, mask);
                     state.save_style_mask.set(Some(curr_mask));
                 }
             }
@@ -1067,21 +1062,26 @@ impl Window2 {
             } else {
                 NSWindowStyleMask::NSBorderlessWindowMask
             };
-
-            state.window.setStyleMask_(new_mask);
+            util::set_style_mask(*state.window, *state.view, new_mask);
         }
     }
 
     #[inline]
     pub fn set_window_icon(&self, _icon: Option<::Icon>) {
         // macOS doesn't have window icons. Though, there is `setRepresentedFilename`, but that's
-        // semantically distinct and should only be used when the window is in some representing a
-        // specific file/directory. For instance, Terminal.app uses this for the CWD. Anyway, that
-        // should eventually be implemented as `WindowBuilderExt::with_represented_file` or
-        // something, and doesn't have anything to do with this.
+        // semantically distinct and should only be used when the window is in some way
+        // representing a specific file/directory. For instance, Terminal.app uses this for the
+        // CWD. Anyway, that should eventually be implemented as
+        // `WindowBuilderExt::with_represented_file` or something, and doesn't have anything to do
+        // with `set_window_icon`.
         // https://developer.apple.com/library/content/documentation/Cocoa/Conceptual/WinPanel/Tasks/SettingWindowTitle.html
     }
 
+    #[inline]
+    pub fn set_ime_spot(&self, x: i32, y: i32) {
+        set_ime_spot(*self.view, *self.input_context, x, y);
+    }
+
     #[inline]
     pub fn get_current_monitor(&self) -> RootMonitorId {
         unsafe {
@@ -1169,8 +1169,7 @@ impl Drop for IdRef {
     fn drop(&mut self) {
         if self.0 != nil {
             unsafe {
-                let autoreleasepool =
-                    NSAutoreleasePool::new(nil);
+                let autoreleasepool = NSAutoreleasePool::new(nil);
                 let _ : () = msg_send![self.0, release];
                 let _ : () = msg_send![autoreleasepool, release];
             };

src/platform/windows/window.rs

@@ -643,6 +643,11 @@ impl Window {
         }
         self.taskbar_icon.replace(taskbar_icon);
     }
+
+    #[inline]
+    pub fn set_ime_spot(&self, _x: i32, _y: i32) {
+        unimplemented!();
+    }
 }
 
 impl Drop for Window {

src/window.rs

@@ -376,6 +376,12 @@ impl Window {
         self.window.set_window_icon(window_icon)
     }
 
+    //// Sets location of IME candidate box in client area coordinates relative to the top left.
+    #[inline]
+    pub fn set_ime_spot(&self, x: i32, y: i32) {
+        self.window.set_ime_spot(x, y)
+    }
+
     /// Returns the monitor on which the window currently resides
     pub fn get_current_monitor(&self) -> MonitorId {
         self.window.get_current_monitor()