Add Window::set_ime_purpose

This adds a way to set the purpose for the IME input, implemented
only on Wayland for now.

CHANGELOG.md

@@ -65,6 +65,7 @@ And please only add new entries to the top of this list, right below the `# Unre
 - On Wayland, support fractional scaling via the wp-fractional-scale protocol.
 - On web, fix removal of mouse event listeners from the global object upon window distruction.
 - Add WindowAttributes getter to WindowBuilder to allow introspection of default values.
+- Added `Window::set_ime_purpose` for setting the IME purpose, currently implemented on Wayland only.
 
 # 0.27.5
 

examples/ime.rs

@@ -6,7 +6,7 @@ use winit::{
     dpi::PhysicalPosition,
     event::{ElementState, Event, Ime, VirtualKeyCode, WindowEvent},
     event_loop::{ControlFlow, EventLoop},
-    window::WindowBuilder,
+    window::{ImePurpose, WindowBuilder},
 };
 
 fn main() {
@@ -18,6 +18,7 @@ fn main() {
     println!("IME position will system default");
     println!("Click to set IME position to cursor's");
     println!("Press F2 to toggle IME. See the documentation of `set_ime_allowed` for more info");
+    println!("Press F3 to cycle through IME purposes.");
 
     let event_loop = EventLoop::new();
 
@@ -26,6 +27,7 @@ fn main() {
         .build(&event_loop)
         .unwrap();
 
+    let mut ime_purpose = ImePurpose::Normal;
     let mut ime_allowed = true;
     window.set_ime_allowed(ime_allowed);
 
@@ -90,7 +92,18 @@ fn main() {
                 {
                     ime_allowed = !ime_allowed;
                     window.set_ime_allowed(ime_allowed);
-                    println!("\nIME: {ime_allowed}\n");
+                    println!("\nIME allowed: {ime_allowed}\n");
+                }
+                if input.state == ElementState::Pressed
+                    && input.virtual_keycode == Some(VirtualKeyCode::F3)
+                {
+                    ime_purpose = match ime_purpose {
+                        ImePurpose::Normal => ImePurpose::Password,
+                        ImePurpose::Password => ImePurpose::Terminal,
+                        _ => ImePurpose::Normal,
+                    };
+                    window.set_ime_purpose(ime_purpose);
+                    println!("\nIME purpose: {ime_purpose:?}\n");
                 }
             }
             _ => (),

src/platform_impl/android/mod.rs

@@ -25,7 +25,9 @@ use crate::{
     error,
     event::{self, StartCause, VirtualKeyCode},
     event_loop::{self, ControlFlow, EventLoopWindowTarget as RootELW},
-    window::{self, CursorGrabMode, ResizeDirection, Theme, WindowButtons, WindowLevel},
+    window::{
+        self, CursorGrabMode, ImePurpose, ResizeDirection, Theme, WindowButtons, WindowLevel,
+    },
 };
 
 static HAS_FOCUS: Lazy<RwLock<bool>> = Lazy::new(|| RwLock::new(true));
@@ -1006,6 +1008,8 @@ impl Window {
 
     pub fn set_ime_allowed(&self, _allowed: bool) {}
 
+    pub fn set_ime_purpose(&self, _purpose: ImePurpose) {}
+
     pub fn focus_window(&self) {}
 
     pub fn request_user_attention(&self, _request_type: Option<window::UserAttentionType>) {}

src/platform_impl/ios/window.rs

@@ -27,8 +27,8 @@ use crate::{
         monitor, EventLoopWindowTarget, Fullscreen, MonitorHandle,
     },
     window::{
-        CursorGrabMode, CursorIcon, ResizeDirection, Theme, UserAttentionType, WindowAttributes,
-        WindowButtons, WindowId as RootWindowId, WindowLevel,
+        CursorGrabMode, CursorIcon, ImePurpose, ResizeDirection, Theme, UserAttentionType,
+        WindowAttributes, WindowButtons, WindowId as RootWindowId, WindowLevel,
     },
 };
 
@@ -303,6 +303,10 @@ impl Inner {
         warn!("`Window::set_ime_allowed` is ignored on iOS")
     }
 
+    pub fn set_ime_purpose(&self, _purpose: ImePurpose) {
+        warn!("`Window::set_ime_allowed` is ignored on iOS")
+    }
+
     pub fn focus_window(&self) {
         warn!("`Window::set_focus` is ignored on iOS")
     }

src/platform_impl/linux/mod.rs

@@ -34,8 +34,8 @@ use crate::{
     },
     icon::Icon,
     window::{
-        CursorGrabMode, CursorIcon, ResizeDirection, Theme, UserAttentionType, WindowAttributes,
-        WindowButtons, WindowLevel,
+        CursorGrabMode, CursorIcon, ImePurpose, ResizeDirection, Theme, UserAttentionType,
+        WindowAttributes, WindowButtons, WindowLevel,
     },
 };
 
@@ -519,6 +519,11 @@ impl Window {
         x11_or_wayland!(match self; Window(w) => w.set_ime_allowed(allowed))
     }
 
+    #[inline]
+    pub fn set_ime_purpose(&self, purpose: ImePurpose) {
+        x11_or_wayland!(match self; Window(w) => w.set_ime_purpose(purpose))
+    }
+
     #[inline]
     pub fn focus_window(&self) {
         match self {

src/platform_impl/linux/wayland/seat/text_input/handlers.rs

@@ -9,7 +9,7 @@ use crate::event::{Ime, WindowEvent};
 use crate::platform_impl::wayland;
 use crate::platform_impl::wayland::event_loop::WinitState;
 
-use super::{Preedit, TextInputHandler, TextInputInner};
+use super::{Preedit, TextInputHandler, TextInputInner, ZwpTextInputV3Ext};
 
 #[inline]
 pub(super) fn handle_text_input(
@@ -32,6 +32,7 @@ pub(super) fn handle_text_input(
             // Enable text input on that surface.
             if window_handle.ime_allowed.get() {
                 text_input.enable();
+                text_input.set_content_type_by_purpose(window_handle.ime_purpose.get());
                 text_input.commit();
                 event_sink.push_window_event(WindowEvent::Ime(Ime::Enabled), window_id);
             }

src/platform_impl/linux/wayland/seat/text_input/mod.rs

@@ -1,10 +1,13 @@
 use sctk::reexports::client::protocol::wl_seat::WlSeat;
 use sctk::reexports::client::Attached;
 use sctk::reexports::protocols::unstable::text_input::v3::client::zwp_text_input_manager_v3::ZwpTextInputManagerV3;
-use sctk::reexports::protocols::unstable::text_input::v3::client::zwp_text_input_v3::ZwpTextInputV3;
+use sctk::reexports::protocols::unstable::text_input::v3::client::zwp_text_input_v3::{
+    ContentHint, ContentPurpose, ZwpTextInputV3,
+};
 
 use crate::platform_impl::wayland::event_loop::WinitState;
 use crate::platform_impl::wayland::WindowId;
+use crate::window::ImePurpose;
 
 mod handlers;
 
@@ -14,6 +17,21 @@ pub struct TextInputHandler {
     text_input: ZwpTextInputV3,
 }
 
+trait ZwpTextInputV3Ext {
+    fn set_content_type_by_purpose(&self, purpose: ImePurpose);
+}
+
+impl ZwpTextInputV3Ext for ZwpTextInputV3 {
+    fn set_content_type_by_purpose(&self, purpose: ImePurpose) {
+        let (hint, purpose) = match purpose {
+            ImePurpose::Normal => (ContentHint::None, ContentPurpose::Normal),
+            ImePurpose::Password => (ContentHint::SensitiveData, ContentPurpose::Password),
+            ImePurpose::Terminal => (ContentHint::None, ContentPurpose::Terminal),
+        };
+        self.set_content_type(hint, purpose);
+    }
+}
+
 impl TextInputHandler {
     #[inline]
     pub fn set_ime_position(&self, x: i32, y: i32) {
@@ -22,8 +40,15 @@ impl TextInputHandler {
     }
 
     #[inline]
-    pub fn set_input_allowed(&self, allowed: bool) {
-        if allowed {
+    pub fn set_content_type_by_purpose(&self, purpose: ImePurpose) {
+        self.text_input.set_content_type_by_purpose(purpose);
+        self.text_input.commit();
+    }
+
+    #[inline]
+    pub fn set_input_allowed(&self, allowed: Option<ImePurpose>) {
+        if let Some(purpose) = allowed {
+            self.text_input.set_content_type_by_purpose(purpose);
             self.text_input.enable();
         } else {
             self.text_input.disable();

src/platform_impl/linux/wayland/window/mod.rs

@@ -21,8 +21,8 @@ use crate::platform_impl::{
     OsError, PlatformSpecificWindowBuilderAttributes as PlatformAttributes,
 };
 use crate::window::{
-    CursorGrabMode, CursorIcon, ResizeDirection, Theme, UserAttentionType, WindowAttributes,
-    WindowButtons,
+    CursorGrabMode, CursorIcon, ImePurpose, ResizeDirection, Theme, UserAttentionType,
+    WindowAttributes, WindowButtons,
 };
 
 use super::env::WindowingFeatures;
@@ -623,6 +623,11 @@ impl Window {
         self.send_request(WindowRequest::AllowIme(allowed));
     }
 
+    #[inline]
+    pub fn set_ime_purpose(&self, purpose: ImePurpose) {
+        self.send_request(WindowRequest::ImePurpose(purpose));
+    }
+
     #[inline]
     pub fn display(&self) -> &Display {
         &self.display

src/platform_impl/linux/wayland/window/shim.rs

@@ -23,7 +23,7 @@ use crate::platform_impl::wayland::protocols::wp_fractional_scale_v1::WpFraction
 use crate::platform_impl::wayland::seat::pointer::WinitPointer;
 use crate::platform_impl::wayland::seat::text_input::TextInputHandler;
 use crate::platform_impl::wayland::WindowId;
-use crate::window::{CursorGrabMode, CursorIcon, Theme, UserAttentionType};
+use crate::window::{CursorGrabMode, CursorIcon, ImePurpose, Theme, UserAttentionType};
 
 use super::WinitFrame;
 
@@ -83,6 +83,9 @@ pub enum WindowRequest {
     /// Enable IME on the given window.
     AllowIme(bool),
 
+    /// Set the IME purpose.
+    ImePurpose(ImePurpose),
+
     /// Mark the window as opaque.
     Transparent(bool),
 
@@ -169,6 +172,9 @@ pub struct WindowHandle {
     /// Allow IME events for that window.
     pub ime_allowed: Cell<bool>,
 
+    /// IME purpose for that window.
+    pub ime_purpose: Cell<ImePurpose>,
+
     /// Wether the window is transparent.
     pub transparent: Cell<bool>,
 
@@ -226,6 +232,7 @@ impl WindowHandle {
             attention_requested: Cell::new(false),
             compositor,
             ime_allowed: Cell::new(false),
+            ime_purpose: Cell::new(ImePurpose::default()),
             has_focus,
         }
     }
@@ -399,8 +406,9 @@ impl WindowHandle {
         self.ime_allowed.replace(allowed);
         let window_id = wayland::make_wid(self.window.surface());
 
+        let purpose = allowed.then(|| self.ime_purpose.get());
         for text_input in self.text_inputs.iter() {
-            text_input.set_input_allowed(allowed);
+            text_input.set_input_allowed(purpose);
         }
 
         let event = if allowed {
@@ -412,6 +420,20 @@ impl WindowHandle {
         event_sink.push_window_event(event, window_id);
     }
 
+    pub fn set_ime_purpose(&self, purpose: ImePurpose) {
+        if self.ime_purpose.get() == purpose {
+            return;
+        }
+
+        self.ime_purpose.replace(purpose);
+
+        if self.ime_allowed.get() {
+            for text_input in self.text_inputs.iter() {
+                text_input.set_content_type_by_purpose(purpose);
+            }
+        }
+    }
+
     pub fn set_cursor_visible(&self, visible: bool) {
         self.cursor_visible.replace(visible);
         let cursor_icon = match visible {
@@ -475,6 +497,9 @@ pub fn handle_window_requests(winit_state: &mut WinitState) {
                     let event_sink = &mut winit_state.event_sink;
                     window_handle.set_ime_allowed(allow, event_sink);
                 }
+                WindowRequest::ImePurpose(purpose) => {
+                    window_handle.set_ime_purpose(purpose);
+                }
                 WindowRequest::SetCursorGrabMode(mode) => {
                     window_handle.set_cursor_grab(mode);
                 }

src/platform_impl/linux/x11/window.rs

@@ -21,7 +21,7 @@ use crate::{
         PlatformSpecificWindowBuilderAttributes, VideoMode as PlatformVideoMode,
     },
     window::{
-        CursorGrabMode, CursorIcon, Icon, ResizeDirection, Theme, UserAttentionType,
+        CursorGrabMode, CursorIcon, Icon, ImePurpose, ResizeDirection, Theme, UserAttentionType,
         WindowAttributes, WindowButtons, WindowLevel,
     },
 };
@@ -1532,6 +1532,9 @@ impl UnownedWindow {
             .send(ImeRequest::Allow(self.xwindow, allowed));
     }
 
+    #[inline]
+    pub fn set_ime_purpose(&self, _purpose: ImePurpose) {}
+
     #[inline]
     pub fn focus_window(&self) {
         let state_atom = unsafe { self.xconn.get_atom_unchecked(b"WM_STATE\0") };

src/platform_impl/macos/window.rs

@@ -33,8 +33,8 @@ use crate::{
         Fullscreen, OsError,
     },
     window::{
-        CursorGrabMode, CursorIcon, ResizeDirection, Theme, UserAttentionType, WindowAttributes,
-        WindowButtons, WindowId as RootWindowId, WindowLevel,
+        CursorGrabMode, CursorIcon, ImePurpose, ResizeDirection, Theme, UserAttentionType,
+        WindowAttributes, WindowButtons, WindowId as RootWindowId, WindowLevel,
     },
 };
 use core_graphics::display::{CGDisplay, CGPoint};
@@ -1154,6 +1154,9 @@ impl WinitWindow {
         unsafe { Id::from_shared(self.view()) }.set_ime_allowed(allowed);
     }
 
+    #[inline]
+    pub fn set_ime_purpose(&self, _purpose: ImePurpose) {}
+
     #[inline]
     pub fn focus_window(&self) {
         let is_minimized = self.isMiniaturized();

src/platform_impl/orbital/window.rs

@@ -12,6 +12,7 @@ use crate::{
     error,
     platform_impl::Fullscreen,
     window,
+    window::ImePurpose,
 };
 
 use super::{
@@ -323,6 +324,9 @@ impl Window {
     #[inline]
     pub fn set_ime_allowed(&self, _allowed: bool) {}
 
+    #[inline]
+    pub fn set_ime_purpose(&self, _purpose: ImePurpose) {}
+
     #[inline]
     pub fn focus_window(&self) {}
 

src/platform_impl/web/window.rs

@@ -3,8 +3,8 @@ use crate::error::{ExternalError, NotSupportedError, OsError as RootOE};
 use crate::event;
 use crate::icon::Icon;
 use crate::window::{
-    CursorGrabMode, CursorIcon, ResizeDirection, Theme, UserAttentionType, WindowAttributes,
-    WindowButtons, WindowId as RootWI, WindowLevel,
+    CursorGrabMode, CursorIcon, ImePurpose, ResizeDirection, Theme, UserAttentionType,
+    WindowAttributes, WindowButtons, WindowId as RootWI, WindowLevel,
 };
 
 use raw_window_handle::{RawDisplayHandle, RawWindowHandle, WebDisplayHandle, WebWindowHandle};
@@ -351,6 +351,11 @@ impl Window {
         // Currently not implemented
     }
 
+    #[inline]
+    pub fn set_ime_purpose(&self, _purpose: ImePurpose) {
+        // Currently not implemented
+    }
+
     #[inline]
     pub fn focus_window(&self) {
         // Currently a no-op as it does not seem there is good support for this on web

src/platform_impl/windows/window.rs

@@ -71,8 +71,8 @@ use crate::{
         Fullscreen, PlatformSpecificWindowBuilderAttributes, WindowId,
     },
     window::{
-        CursorGrabMode, CursorIcon, ResizeDirection, Theme, UserAttentionType, WindowAttributes,
-        WindowButtons, WindowLevel,
+        CursorGrabMode, CursorIcon, ImePurpose, ResizeDirection, Theme, UserAttentionType,
+        WindowAttributes, WindowButtons, WindowLevel,
     },
 };
 
@@ -733,6 +733,9 @@ impl Window {
         }
     }
 
+    #[inline]
+    pub fn set_ime_purpose(&self, _purpose: ImePurpose) {}
+
     #[inline]
     pub fn request_user_attention(&self, request_type: Option<UserAttentionType>) {
         let window = self.window.clone();

src/window.rs

@@ -1054,6 +1054,16 @@ impl Window {
         self.window.set_ime_allowed(allowed);
     }
 
+    /// Sets the IME purpose for the window using [`ImePurpose`].
+    ///
+    /// ## Platform-specific
+    ///
+    /// - **iOS / Android / Web / Windows / X11 / macOS / Orbital:** Unsupported.
+    #[inline]
+    pub fn set_ime_purpose(&self, purpose: ImePurpose) {
+        self.window.set_ime_purpose(purpose);
+    }
+
     /// Brings the window to the front and sets input focus. Has no effect if the window is
     /// already in focus, minimized, or not visible.
     ///
@@ -1545,3 +1555,30 @@ impl Default for WindowLevel {
         Self::Normal
     }
 }
+
+/// Generic IME purposes for use in [`Window::set_ime_purpose`].
+///
+/// The purpose may improve UX by optimizing the IME for the specific use case,
+/// if winit can express the purpose to the platform and the platform reacts accordingly.
+///
+/// ## Platform-specific
+///
+/// - **iOS / Android / Web / Windows / X11 / macOS / Orbital:** Unsupported.
+#[derive(Debug, PartialEq, Eq, Clone, Copy)]
+#[non_exhaustive]
+pub enum ImePurpose {
+    /// No special hints for the IME (default).
+    Normal,
+    /// The IME is used for password input.
+    Password,
+    /// The IME is used to input into a terminal.
+    ///
+    /// For example, that could alter OSK on Wayland to show extra buttons.
+    Terminal,
+}
+
+impl Default for ImePurpose {
+    fn default() -> Self {
+        Self::Normal
+    }
+}