i_slint_core/api.rs
1// Copyright © SixtyFPS GmbH <info@slint.dev>
2// SPDX-License-Identifier: GPL-3.0-only OR LicenseRef-Slint-Royalty-free-2.0 OR LicenseRef-Slint-Software-3.0
3
4/*!
5This module contains types that are public and re-exported in the slint-rs as well as the slint-interpreter crate as public API.
6*/
7
8#![warn(missing_docs)]
9
10use crate::input::{BackendMouseEvent, InternalKeyEvent, KeyEventType, MouseEvent, TouchPhase};
11use crate::platform::WindowEventDispatchResult;
12use crate::window::{WindowAdapter, WindowInner};
13use alloc::boxed::Box;
14use alloc::string::String;
15
16pub use crate::data_transfer::DataTransfer;
17#[cfg(target_has_atomic = "ptr")]
18pub use crate::future::*;
19pub use crate::graphics::{
20 Brush, Color, Image, LoadImageError, OklchColor, Rgb8Pixel, Rgba8Pixel, RgbaColor,
21 SharedPixelBuffer,
22};
23pub use crate::input::Keys;
24pub use crate::sharedvector::SharedVector;
25pub use crate::{format, string::SharedString, string::ToSharedString};
26
27/// A position represented in the coordinate space of logical pixels. That is the space before applying
28/// a display device specific scale factor.
29#[derive(Debug, Default, Copy, Clone, PartialEq)]
30#[repr(C)]
31#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
32pub struct LogicalPosition {
33 /// The x coordinate.
34 pub x: f32,
35 /// The y coordinate.
36 pub y: f32,
37}
38
39impl LogicalPosition {
40 /// Construct a new logical position from the given x and y coordinates, that are assumed to be
41 /// in the logical coordinate space.
42 pub const fn new(x: f32, y: f32) -> Self {
43 Self { x, y }
44 }
45
46 /// Convert a given physical position to a logical position by dividing the coordinates with the
47 /// specified scale factor.
48 pub fn from_physical(physical_pos: PhysicalPosition, scale_factor: f32) -> Self {
49 Self::new(physical_pos.x as f32 / scale_factor, physical_pos.y as f32 / scale_factor)
50 }
51
52 /// Convert this logical position to a physical position by multiplying the coordinates with the
53 /// specified scale factor.
54 pub fn to_physical(&self, scale_factor: f32) -> PhysicalPosition {
55 PhysicalPosition::from_logical(*self, scale_factor)
56 }
57
58 pub(crate) fn to_euclid(self) -> crate::lengths::LogicalPoint {
59 [self.x as _, self.y as _].into()
60 }
61 pub(crate) fn from_euclid(p: crate::lengths::LogicalPoint) -> Self {
62 Self::new(p.x as _, p.y as _)
63 }
64}
65
66/// A position represented in the coordinate space of physical device pixels. That is the space after applying
67/// a display device specific scale factor to pixels from the logical coordinate space.
68#[derive(Debug, Default, Copy, Clone, Eq, PartialEq)]
69#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
70pub struct PhysicalPosition {
71 /// The x coordinate.
72 pub x: i32,
73 /// The y coordinate.
74 pub y: i32,
75}
76
77impl PhysicalPosition {
78 /// Construct a new physical position from the given x and y coordinates, that are assumed to be
79 /// in the physical coordinate space.
80 pub const fn new(x: i32, y: i32) -> Self {
81 Self { x, y }
82 }
83
84 /// Convert a given logical position to a physical position by multiplying the coordinates with the
85 /// specified scale factor.
86 pub fn from_logical(logical_pos: LogicalPosition, scale_factor: f32) -> Self {
87 Self::new((logical_pos.x * scale_factor) as i32, (logical_pos.y * scale_factor) as i32)
88 }
89
90 /// Convert this physical position to a logical position by dividing the coordinates with the
91 /// specified scale factor.
92 pub fn to_logical(&self, scale_factor: f32) -> LogicalPosition {
93 LogicalPosition::from_physical(*self, scale_factor)
94 }
95
96 #[cfg(feature = "ffi")]
97 pub(crate) fn to_euclid(self) -> crate::graphics::euclid::default::Point2D<i32> {
98 [self.x, self.y].into()
99 }
100
101 #[cfg(feature = "ffi")]
102 pub(crate) fn from_euclid(p: crate::graphics::euclid::default::Point2D<i32>) -> Self {
103 Self::new(p.x as _, p.y as _)
104 }
105}
106
107/// The position of the window in either physical or logical pixels. This is used
108/// with [`Window::set_position`].
109#[derive(Clone, Debug, derive_more::From, PartialEq)]
110pub enum WindowPosition {
111 /// The position in physical pixels.
112 Physical(PhysicalPosition),
113 /// The position in logical pixels.
114 Logical(LogicalPosition),
115}
116
117impl WindowPosition {
118 /// Turn the `WindowPosition` into a `PhysicalPosition`.
119 pub fn to_physical(&self, scale_factor: f32) -> PhysicalPosition {
120 match self {
121 WindowPosition::Physical(pos) => *pos,
122 WindowPosition::Logical(pos) => pos.to_physical(scale_factor),
123 }
124 }
125}
126
127/// A size represented in the coordinate space of logical pixels. That is the space before applying
128/// a display device specific scale factor.
129#[repr(C)]
130#[derive(Debug, Default, Copy, Clone, PartialEq)]
131#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
132pub struct LogicalSize {
133 /// The width in logical pixels.
134 pub width: f32,
135 /// The height in logical.
136 pub height: f32,
137}
138
139impl LogicalSize {
140 /// Construct a new logical size from the given width and height values, that are assumed to be
141 /// in the logical coordinate space.
142 pub const fn new(width: f32, height: f32) -> Self {
143 Self { width, height }
144 }
145
146 /// Convert a given physical size to a logical size by dividing width and height by the
147 /// specified scale factor.
148 pub fn from_physical(physical_size: PhysicalSize, scale_factor: f32) -> Self {
149 Self::new(
150 physical_size.width as f32 / scale_factor,
151 physical_size.height as f32 / scale_factor,
152 )
153 }
154
155 /// Convert this logical size to a physical size by multiplying width and height with the
156 /// specified scale factor.
157 pub fn to_physical(&self, scale_factor: f32) -> PhysicalSize {
158 PhysicalSize::from_logical(*self, scale_factor)
159 }
160
161 pub(crate) fn to_euclid(self) -> crate::lengths::LogicalSize {
162 [self.width as _, self.height as _].into()
163 }
164
165 pub(crate) fn from_euclid(p: crate::lengths::LogicalSize) -> Self {
166 Self::new(p.width as _, p.height as _)
167 }
168}
169
170/// A size represented in the coordinate space of physical device pixels. That is the space after applying
171/// a display device specific scale factor to pixels from the logical coordinate space.
172#[derive(Debug, Default, Copy, Clone, Eq, PartialEq)]
173#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
174pub struct PhysicalSize {
175 /// The width in physical pixels.
176 pub width: u32,
177 /// The height in physical pixels;
178 pub height: u32,
179}
180
181impl PhysicalSize {
182 /// Construct a new physical size from the width and height values, that are assumed to be
183 /// in the physical coordinate space.
184 pub const fn new(width: u32, height: u32) -> Self {
185 Self { width, height }
186 }
187
188 /// Convert a given logical size to a physical size by multiplying width and height with the
189 /// specified scale factor.
190 pub fn from_logical(logical_size: LogicalSize, scale_factor: f32) -> Self {
191 Self::new(
192 (logical_size.width * scale_factor) as u32,
193 (logical_size.height * scale_factor) as u32,
194 )
195 }
196
197 /// Convert this physical size to a logical size by dividing width and height by the
198 /// specified scale factor.
199 pub fn to_logical(&self, scale_factor: f32) -> LogicalSize {
200 LogicalSize::from_physical(*self, scale_factor)
201 }
202
203 #[cfg(feature = "ffi")]
204 pub(crate) fn to_euclid(self) -> crate::graphics::euclid::default::Size2D<u32> {
205 [self.width, self.height].into()
206 }
207}
208
209/// The size of a window represented in either physical or logical pixels. This is used
210/// with [`Window::set_size`].
211#[derive(Clone, Debug, derive_more::From, PartialEq)]
212pub enum WindowSize {
213 /// The size in physical pixels.
214 Physical(PhysicalSize),
215 /// The size in logical screen pixels.
216 Logical(LogicalSize),
217}
218
219impl WindowSize {
220 /// Turn the `WindowSize` into a `PhysicalSize`.
221 pub fn to_physical(&self, scale_factor: f32) -> PhysicalSize {
222 match self {
223 WindowSize::Physical(size) => *size,
224 WindowSize::Logical(size) => size.to_physical(scale_factor),
225 }
226 }
227
228 /// Turn the `WindowSize` into a `LogicalSize`.
229 pub fn to_logical(&self, scale_factor: f32) -> LogicalSize {
230 match self {
231 WindowSize::Physical(size) => size.to_logical(scale_factor),
232 WindowSize::Logical(size) => *size,
233 }
234 }
235}
236
237#[test]
238fn logical_physical_pos() {
239 use crate::graphics::euclid::approxeq::ApproxEq;
240
241 let phys = PhysicalPosition::new(100, 50);
242 let logical = phys.to_logical(2.);
243 assert!(logical.x.approx_eq(&50.));
244 assert!(logical.y.approx_eq(&25.));
245
246 assert_eq!(logical.to_physical(2.), phys);
247}
248
249#[test]
250fn logical_physical_size() {
251 use crate::graphics::euclid::approxeq::ApproxEq;
252
253 let phys = PhysicalSize::new(100, 50);
254 let logical = phys.to_logical(2.);
255 assert!(logical.width.approx_eq(&50.));
256 assert!(logical.height.approx_eq(&25.));
257
258 assert_eq!(logical.to_physical(2.), phys);
259}
260
261#[i_slint_core_macros::slint_doc]
262/// This enum describes a low-level access to specific graphics APIs used
263/// by the renderer.
264#[derive(Clone)]
265#[non_exhaustive]
266pub enum GraphicsAPI<'a> {
267 /// The rendering is done using OpenGL.
268 NativeOpenGL {
269 /// Use this function pointer to obtain access to the OpenGL implementation - similar to `eglGetProcAddress`.
270 get_proc_address: &'a dyn Fn(&core::ffi::CStr) -> *const core::ffi::c_void,
271 },
272 /// The rendering is done on a HTML Canvas element using WebGL.
273 WebGL {
274 /// The DOM element id of the HTML Canvas element used for rendering.
275 canvas_element_id: &'a str,
276 /// The drawing context type used on the HTML Canvas element for rendering. This is the argument to the
277 /// `getContext` function on the HTML Canvas element.
278 context_type: &'a str,
279 },
280 /// The rendering is based on WGPU 29.x. Use the provided fields to submit commits to the provided
281 /// WGPU command queue.
282 ///
283 /// *Note*: This function is behind the [`unstable-wgpu-29` feature flag](slint:rust:slint/docs/cargo_features/#backends)
284 /// and may be removed or changed in future minor releases, as new major WGPU releases become available.
285 ///
286 /// See also the [`slint::wgpu_29`](slint:rust:slint/wgpu_29) module.
287 #[cfg(feature = "unstable-wgpu-29")]
288 #[non_exhaustive]
289 WGPU29 {
290 /// The WGPU instance used for rendering.
291 instance: wgpu_29::Instance,
292 /// The WGPU device used for rendering.
293 device: wgpu_29::Device,
294 /// The WGPU queue for used for command submission.
295 queue: wgpu_29::Queue,
296 },
297 /// The rendering is based on WGPU 30.x. Use the provided fields to submit commits to the provided
298 /// WGPU command queue.
299 ///
300 /// *Note*: This function is behind the [`unstable-wgpu-30` feature flag](slint:rust:slint/docs/cargo_features/#backends)
301 /// and may be removed or changed in future minor releases, as new major WGPU releases become available.
302 ///
303 /// See also the [`slint::wgpu_30`](slint:rust:slint/wgpu_30) module.
304 #[cfg(feature = "unstable-wgpu-30")]
305 #[non_exhaustive]
306 WGPU30 {
307 /// The WGPU instance used for rendering.
308 instance: wgpu_30::Instance,
309 /// The WGPU device used for rendering.
310 device: wgpu_30::Device,
311 /// The WGPU queue for used for command submission.
312 queue: wgpu_30::Queue,
313 },
314}
315
316impl core::fmt::Debug for GraphicsAPI<'_> {
317 fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
318 match self {
319 GraphicsAPI::NativeOpenGL { .. } => write!(f, "GraphicsAPI::NativeOpenGL"),
320 GraphicsAPI::WebGL { context_type, .. } => {
321 write!(f, "GraphicsAPI::WebGL(context_type = {context_type})")
322 }
323 #[cfg(feature = "unstable-wgpu-29")]
324 GraphicsAPI::WGPU29 { .. } => write!(f, "GraphicsAPI::WGPU29"),
325 #[cfg(feature = "unstable-wgpu-30")]
326 GraphicsAPI::WGPU30 { .. } => write!(f, "GraphicsAPI::WGPU30"),
327 }
328 }
329}
330
331/// This enum describes the different rendering states, that will be provided
332/// to the parameter of the callback for `set_rendering_notifier` on the `slint::Window`.
333///
334/// When OpenGL is used for rendering, the context will be current.
335/// It's safe to call OpenGL functions, but it is crucial that the state of the context is
336/// preserved. So make sure to save and restore state such as `TEXTURE_BINDING_2D` or
337/// `ARRAY_BUFFER_BINDING` perfectly.
338#[derive(Debug, Clone)]
339#[repr(u8)]
340#[non_exhaustive]
341pub enum RenderingState {
342 /// The window has been created and the graphics adapter/context initialized.
343 RenderingSetup,
344 /// The scene of items is about to be rendered.
345 BeforeRendering,
346 /// The scene of items was rendered, but the back buffer was not sent for display presentation
347 /// yet (for example GL swap buffers).
348 AfterRendering,
349 /// The window will be destroyed and/or graphics resources need to be released due to other
350 /// constraints.
351 RenderingTeardown,
352}
353
354/// Internal trait that's used to map rendering state callbacks to either a Rust-API provided
355/// impl FnMut or a struct that invokes a C callback and implements Drop to release the closure
356/// on the C++ side.
357#[doc(hidden)]
358pub trait RenderingNotifier {
359 /// Called to notify that rendering has reached a certain state.
360 fn notify(&mut self, state: RenderingState, graphics_api: &GraphicsAPI);
361}
362
363impl<F: FnMut(RenderingState, &GraphicsAPI)> RenderingNotifier for F {
364 fn notify(&mut self, state: RenderingState, graphics_api: &GraphicsAPI) {
365 self(state, graphics_api)
366 }
367}
368
369/// This enum describes the different error scenarios that may occur when the application
370/// registers a rendering notifier on a `slint::Window`.
371#[derive(Debug, Clone)]
372#[repr(u8)]
373#[non_exhaustive]
374pub enum SetRenderingNotifierError {
375 /// The rendering backend does not support rendering notifiers.
376 Unsupported,
377 /// There is already a rendering notifier set, multiple notifiers are not supported.
378 AlreadySet,
379}
380
381impl core::fmt::Display for SetRenderingNotifierError {
382 fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
383 match self {
384 Self::Unsupported => {
385 f.write_str("The rendering backend does not support rendering notifiers.")
386 }
387 Self::AlreadySet => f.write_str(
388 "There is already a rendering notifier set, multiple notifiers are not supported.",
389 ),
390 }
391 }
392}
393
394#[cfg(feature = "std")]
395impl std::error::Error for SetRenderingNotifierError {}
396
397#[cfg(feature = "raw-window-handle-06")]
398#[derive(Clone)]
399enum WindowHandleInner {
400 HandleByAdapter(alloc::rc::Rc<dyn WindowAdapter>),
401 #[cfg(feature = "std")]
402 HandleByRcRWH {
403 window_handle_provider: std::sync::Arc<dyn raw_window_handle_06::HasWindowHandle>,
404 display_handle_provider: std::sync::Arc<dyn raw_window_handle_06::HasDisplayHandle>,
405 },
406}
407
408/// This struct represents a persistent handle to a window and implements the
409/// [`raw_window_handle_06::HasWindowHandle`] and [`raw_window_handle_06::HasDisplayHandle`]
410/// traits for accessing exposing raw window and display handles.
411/// Obtain an instance of this by calling [`Window::window_handle()`].
412#[cfg(feature = "raw-window-handle-06")]
413#[derive(Clone)]
414pub struct WindowHandle {
415 inner: WindowHandleInner,
416}
417
418#[cfg(feature = "raw-window-handle-06")]
419impl raw_window_handle_06::HasWindowHandle for WindowHandle {
420 fn window_handle(
421 &self,
422 ) -> Result<raw_window_handle_06::WindowHandle<'_>, raw_window_handle_06::HandleError> {
423 match &self.inner {
424 WindowHandleInner::HandleByAdapter(adapter) => adapter.window_handle_06(),
425 #[cfg(feature = "std")]
426 WindowHandleInner::HandleByRcRWH { window_handle_provider, .. } => {
427 window_handle_provider.window_handle()
428 }
429 }
430 }
431}
432
433#[cfg(feature = "raw-window-handle-06")]
434impl raw_window_handle_06::HasDisplayHandle for WindowHandle {
435 fn display_handle(
436 &self,
437 ) -> Result<raw_window_handle_06::DisplayHandle<'_>, raw_window_handle_06::HandleError> {
438 match &self.inner {
439 WindowHandleInner::HandleByAdapter(adapter) => adapter.display_handle_06(),
440 #[cfg(feature = "std")]
441 WindowHandleInner::HandleByRcRWH { display_handle_provider, .. } => {
442 display_handle_provider.display_handle()
443 }
444 }
445 }
446}
447
448/// This type represents a window towards the windowing system, that's used to render the
449/// scene of a component. It provides API to control windowing system specific aspects such
450/// as the position on the screen.
451#[repr(transparent)]
452pub struct Window(pub(crate) WindowInner);
453
454/// This enum describes whether a Window is allowed to be hidden when the user tries to close the window.
455/// It is the return type of the callback provided to [Window::on_close_requested].
456#[derive(Copy, Clone, Debug, PartialEq, Default)]
457#[repr(u8)]
458pub enum CloseRequestResponse {
459 /// The Window will be hidden (default action)
460 #[default]
461 HideWindow = 0,
462 /// The close request is rejected and the window will be kept shown.
463 KeepWindowShown = 1,
464}
465
466impl Window {
467 /// Create a new window from a window adapter
468 ///
469 /// You only need to create the window yourself when you create a [`WindowAdapter`] from
470 /// [`Platform::create_window_adapter`](crate::platform::Platform::create_window_adapter)
471 ///
472 /// Since the window adapter must own the Window, this function is meant to be used with
473 /// [`Rc::new_cyclic`](alloc::rc::Rc::new_cyclic)
474 ///
475 /// # Example
476 /// ```rust
477 /// use std::rc::Rc;
478 /// use slint::platform::{WindowAdapter, Renderer};
479 /// use slint::{Window, PhysicalSize};
480 /// struct MyWindowAdapter {
481 /// window: Window,
482 /// //...
483 /// }
484 /// impl WindowAdapter for MyWindowAdapter {
485 /// fn window(&self) -> &Window { &self.window }
486 /// fn size(&self) -> PhysicalSize { unimplemented!() }
487 /// fn renderer(&self) -> &dyn Renderer { unimplemented!() }
488 /// }
489 ///
490 /// fn create_window_adapter() -> Rc<dyn WindowAdapter> {
491 /// Rc::<MyWindowAdapter>::new_cyclic(|weak| {
492 /// MyWindowAdapter {
493 /// window: Window::new(weak.clone()),
494 /// //...
495 /// }
496 /// })
497 /// }
498 /// ```
499 pub fn new(window_adapter_weak: alloc::rc::Weak<dyn WindowAdapter>) -> Self {
500 Self(WindowInner::new(window_adapter_weak))
501 }
502
503 /// Shows the window on the screen. An additional strong reference on the
504 /// associated component is maintained while the window is visible.
505 ///
506 /// Call [`Self::hide()`] to make the window invisible again, and drop the additional
507 /// strong reference.
508 pub fn show(&self) -> Result<(), PlatformError> {
509 self.0.show()
510 }
511
512 /// Hides the window, so that it is not visible anymore. The additional strong
513 /// reference on the associated component, that was created when [`Self::show()`] was called, is
514 /// dropped.
515 pub fn hide(&self) -> Result<(), PlatformError> {
516 self.0.hide()
517 }
518
519 /// This function allows registering a callback that's invoked during the different phases of
520 /// rendering. This allows custom rendering on top or below of the scene.
521 pub fn set_rendering_notifier(
522 &self,
523 callback: impl FnMut(RenderingState, &GraphicsAPI) + 'static,
524 ) -> Result<(), SetRenderingNotifierError> {
525 self.0.window_adapter().renderer().set_rendering_notifier(Box::new(callback))
526 }
527
528 /// This function allows registering a callback that's invoked when the user tries to close a window.
529 /// The callback has to return a [CloseRequestResponse].
530 pub fn on_close_requested(&self, callback: impl FnMut() -> CloseRequestResponse + 'static) {
531 self.0.on_close_requested(callback);
532 }
533
534 /// This function issues a request to the windowing system to redraw the contents of the window.
535 pub fn request_redraw(&self) {
536 self.0.window_adapter().request_redraw()
537 }
538
539 /// This function returns the scale factor that allows converting between logical and
540 /// physical pixels.
541 pub fn scale_factor(&self) -> f32 {
542 self.0.scale_factor()
543 }
544
545 /// Returns the position of the window on the screen, in physical screen coordinates and including
546 /// a window frame (if present).
547 pub fn position(&self) -> PhysicalPosition {
548 self.0.window_adapter().position().unwrap_or_default()
549 }
550
551 /// Sets the position of the window on the screen, in physical screen coordinates and including
552 /// a window frame (if present).
553 /// Note that on some windowing systems, such as Wayland, this functionality is not available.
554 pub fn set_position(&self, position: impl Into<WindowPosition>) {
555 let position = position.into();
556 self.0.window_adapter().set_position(position)
557 }
558
559 /// Returns the size of the window on the screen, in physical screen coordinates and excluding
560 /// a window frame (if present).
561 pub fn size(&self) -> PhysicalSize {
562 self.0.window_adapter().size()
563 }
564
565 /// Resizes the window to the specified size on the screen, in physical pixels and excluding
566 /// a window frame (if present).
567 pub fn set_size(&self, size: impl Into<WindowSize>) {
568 let size = size.into();
569 crate::window::WindowAdapter::set_size(&*self.0.window_adapter(), size);
570 }
571
572 /// Returns if the window is currently fullscreen
573 pub fn is_fullscreen(&self) -> bool {
574 self.0.is_fullscreen()
575 }
576
577 /// Set or unset the window to display fullscreen.
578 pub fn set_fullscreen(&self, fullscreen: bool) {
579 self.0.set_fullscreen(fullscreen);
580 }
581
582 /// Returns if the window is currently maximized
583 pub fn is_maximized(&self) -> bool {
584 self.0.is_maximized()
585 }
586
587 /// Maximize or unmaximize the window.
588 pub fn set_maximized(&self, maximized: bool) {
589 self.0.set_maximized(maximized);
590 }
591
592 /// Returns if the window is currently minimized
593 pub fn is_minimized(&self) -> bool {
594 self.0.is_minimized()
595 }
596
597 /// Minimize or unminimize the window.
598 pub fn set_minimized(&self, minimized: bool) {
599 self.0.set_minimized(minimized);
600 }
601
602 /// The area of the window covered by the software keyboard is changing (animated).
603 #[doc(hidden)]
604 pub fn set_virtual_keyboard(
605 &self,
606 origin: LogicalPosition,
607 size: LogicalSize,
608 _: crate::InternalToken,
609 ) {
610 self.0.set_window_item_virtual_keyboard(origin.to_euclid(), size.to_euclid());
611 }
612
613 #[doc(hidden)]
614 pub fn virtual_keyboard(
615 &self,
616 _: crate::InternalToken,
617 ) -> Option<(LogicalPosition, LogicalSize)> {
618 self.0.window_item_virtual_keyboard().map(|(origin, size)| {
619 (LogicalPosition::from_euclid(origin), LogicalSize::from_euclid(size))
620 })
621 }
622
623 /// Dispatch a window event to the scene.
624 ///
625 /// Use this when you're implementing your own backend and want to forward user input events.
626 ///
627 /// Any position fields in the event must be in the logical pixel coordinate system relative to
628 /// the top left corner of the window.
629 ///
630 /// This function panics if there is an error processing the event.
631 /// Use [`Self::dispatch_event_with_result()`] to handle the error.
632 #[track_caller]
633 pub fn dispatch_event(&self, event: crate::platform::WindowEvent) {
634 self.dispatch_event_with_result(event).unwrap();
635 }
636
637 /// Dispatch a window event to the scene.
638 ///
639 /// Use this when you're implementing your own backend and want to forward user input events.
640 ///
641 /// Any position fields in the event must be in the logical pixel coordinate system relative to
642 /// the top left corner of the window.
643 #[deprecated(note = "use `dispatch_event_with_result` instead")]
644 pub fn try_dispatch_event(
645 &self,
646 event: crate::platform::WindowEvent,
647 ) -> Result<(), PlatformError> {
648 self.dispatch_event_with_result(event).map(|_| ())
649 }
650
651 /// Dispatch a window event to the scene.
652 ///
653 /// Use this when you're implementing your own backend and want to forward user input events.
654 ///
655 /// Any position fields in the event must be in the logical pixel coordinate system relative to
656 /// the top left corner of the window.
657 ///
658 /// Returns a [`WindowEventDispatchResult`] indicating how the event was handled.
659 pub fn dispatch_event_with_result(
660 &self,
661 event: crate::platform::WindowEvent,
662 ) -> Result<WindowEventDispatchResult, PlatformError> {
663 // Only clone the event when a hook is installed to avoid allocation on the hot path.
664 // Events a backend delivers in the internal representation are reported as the public
665 // event they correspond to, if there is one.
666 let hook_installed =
667 self.0.try_context().is_some_and(|ctx| ctx.0.window_event_hook.borrow().is_some());
668 let event_for_hook = hook_installed
669 .then(|| match &event {
670 crate::platform::WindowEvent::Internal(event) => event.public_representation(),
671 event => Some(event.clone()),
672 })
673 .flatten();
674 let dispatch_result = match event {
675 crate::platform::WindowEvent::PointerPressed { position, button } => self
676 .0
677 .process_mouse_input(MouseEvent::Pressed {
678 position: position.to_euclid().cast(),
679 button,
680 click_count: 0,
681 touch_finger_id: 0,
682 })
683 .into(),
684 crate::platform::WindowEvent::PointerReleased { position, button } => self
685 .0
686 .process_mouse_input(MouseEvent::Released {
687 position: position.to_euclid().cast(),
688 button,
689 click_count: 0,
690 touch_finger_id: 0,
691 })
692 .into(),
693 crate::platform::WindowEvent::PointerMoved { position } => self
694 .0
695 .process_mouse_input(MouseEvent::Moved {
696 position: position.to_euclid().cast(),
697 touch_finger_id: 0,
698 })
699 .into(),
700 crate::platform::WindowEvent::PointerScrolled { position, delta_x, delta_y } => self
701 .0
702 .process_mouse_input(MouseEvent::Wheel {
703 position: position.to_euclid().cast(),
704 delta_x: delta_x as _,
705 delta_y: delta_y as _,
706 phase: TouchPhase::Cancelled,
707 })
708 .into(),
709 crate::platform::WindowEvent::PointerExited => {
710 // Teardown event — the runtime always acts on it (clears hover/grab state
711 // and dispatches Exit to the item stack), so report Accepted unconditionally
712 // rather than asking the hit-test whether anything consumed it.
713 self.0.process_mouse_input(MouseEvent::Exit);
714 WindowEventDispatchResult::Accepted
715 }
716
717 crate::platform::WindowEvent::KeyPressed { text } => self
718 .0
719 .process_key_input(InternalKeyEvent {
720 event_type: KeyEventType::KeyPressed,
721 key_event: crate::input::KeyEvent { text, ..Default::default() },
722 ..Default::default()
723 })
724 .into(),
725 crate::platform::WindowEvent::KeyPressRepeated { text } => self
726 .0
727 .process_key_input(InternalKeyEvent {
728 event_type: KeyEventType::KeyPressed,
729 key_event: crate::input::KeyEvent { text, repeat: true, ..Default::default() },
730 ..Default::default()
731 })
732 .into(),
733 crate::platform::WindowEvent::KeyReleased { text } => self
734 .0
735 .process_key_input(InternalKeyEvent {
736 event_type: KeyEventType::KeyReleased,
737 key_event: crate::input::KeyEvent { text, ..Default::default() },
738 ..Default::default()
739 })
740 .into(),
741 crate::platform::WindowEvent::ScaleFactorChanged { scale_factor } => {
742 self.0.set_scale_factor(scale_factor);
743 WindowEventDispatchResult::Accepted
744 }
745 crate::platform::WindowEvent::Resized { size } => {
746 self.0.set_window_item_geometry(size.to_euclid());
747 self.0.window_adapter().renderer().resize(size.to_physical(self.scale_factor()))?;
748 if let Some(item_rc) = self.0.focus_item.borrow().upgrade() {
749 item_rc.try_scroll_into_visible();
750 }
751 WindowEventDispatchResult::Accepted
752 }
753 crate::platform::WindowEvent::CloseRequested => {
754 if self.0.request_close() {
755 self.hide()?;
756 WindowEventDispatchResult::Accepted
757 } else {
758 WindowEventDispatchResult::Rejected
759 }
760 }
761 crate::platform::WindowEvent::WindowActiveChanged(bool) => {
762 self.0.set_active(bool);
763 WindowEventDispatchResult::Accepted
764 }
765 crate::platform::WindowEvent::Internal(event) => match event.into_inner() {
766 crate::platform::InternalEvent::Mouse(BackendMouseEvent::Exit) => {
767 // Teardown event, always accepted like `WindowEvent::PointerExited`.
768 self.0.process_mouse_input(MouseEvent::Exit);
769 WindowEventDispatchResult::Accepted
770 }
771 crate::platform::InternalEvent::Mouse(event) => {
772 self.0.process_mouse_input(event.into()).into()
773 }
774 crate::platform::InternalEvent::Key(event) => {
775 self.0.process_key_input(event).into()
776 }
777 crate::platform::InternalEvent::Touch { id, position, phase } => {
778 self.0.process_touch_input(id, position, phase).into()
779 }
780 },
781 };
782 if let Some(event_for_hook) = event_for_hook
783 && let Some(ctx) = self.0.try_context()
784 && let Some(hook) = ctx.0.window_event_hook.borrow().as_ref()
785 {
786 hook(&self.0.window_adapter(), &event_for_hook, dispatch_result.clone());
787 }
788 Ok(dispatch_result)
789 }
790
791 /// Returns true if there is an animation currently active on any property in the Window; false otherwise.
792 pub fn has_active_animations(&self) -> bool {
793 // TODO make it really per window.
794 crate::animations::CURRENT_ANIMATION_DRIVER.with(|driver| driver.has_active_animations())
795 }
796
797 /// Returns the visibility state of the window. This function can return false even if you previously called show()
798 /// on it, for example if the user minimized the window.
799 pub fn is_visible(&self) -> bool {
800 self.0.is_visible()
801 }
802
803 /// Returns a struct that implements the raw window handle traits to access the windowing system specific window
804 /// and display handles.
805 ///
806 /// Note that the window handle may only become available after the window has been created by the window manager,
807 /// which typically occurs after at least one iteration of the event loop following a call to `show()`.
808 ///
809 /// Support for this function depends on the platform backend.
810 ///
811 /// This function is only accessible if you enable the `raw-window-handle-06` crate feature.
812 #[cfg(feature = "raw-window-handle-06")]
813 pub fn window_handle(&self) -> WindowHandle {
814 let adapter = self.0.window_adapter();
815 #[cfg(feature = "std")]
816 if let Some((window_handle_provider, display_handle_provider)) =
817 adapter.internal(crate::InternalToken).and_then(|internal| {
818 internal.window_handle_06_rc().ok().zip(internal.display_handle_06_rc().ok())
819 })
820 {
821 return WindowHandle {
822 inner: WindowHandleInner::HandleByRcRWH {
823 window_handle_provider,
824 display_handle_provider,
825 },
826 };
827 }
828
829 WindowHandle { inner: WindowHandleInner::HandleByAdapter(adapter) }
830 }
831
832 /// Takes a snapshot of the window contents and returns it as RGBA8 encoded pixel buffer.
833 ///
834 /// Note that this function may be slow to call as it may need to re-render the scene.
835 ///
836 /// Only available with the `std` feature.
837 #[cfg(feature = "std")]
838 pub fn take_snapshot(&self) -> Result<SharedPixelBuffer<Rgba8Pixel>, PlatformError> {
839 self.0.window_adapter().renderer().take_snapshot()
840 }
841}
842
843#[i_slint_core_macros::slint_doc]
844/// This trait is used to obtain references to global singletons exported in `.slint`
845/// markup. Alternatively, you can use [`ComponentHandle::global`] to obtain access.
846///
847/// This trait is implemented by the compiler for each global singleton that's exported.
848///
849/// # Example
850/// The following example of `.slint` markup defines a global singleton called `Palette`, exports
851/// it and modifies it from Rust code:
852/// ```rust
853/// # i_slint_backend_testing::init_no_event_loop();
854/// slint::slint!{
855/// export global Palette {
856/// in property<color> foreground-color;
857/// in property<color> background-color;
858/// }
859///
860/// export component App inherits Window {
861/// background: Palette.background-color;
862/// Text {
863/// text: "Hello";
864/// color: Palette.foreground-color;
865/// }
866/// // ...
867/// }
868/// }
869/// let app = App::new().unwrap();
870/// app.global::<Palette>().set_background_color(slint::Color::from_rgb_u8(0, 0, 0));
871///
872/// // alternate way to access the global singleton:
873/// Palette::get(&app).set_foreground_color(slint::Color::from_rgb_u8(255, 255, 255));
874/// ```
875///
876/// See also the [language documentation for global singletons](slint:globals) for more information.
877///
878/// **Note:** Only globals that are exported or re-exported from the main .slint file will
879/// be exposed in the API
880///
881/// # Storing References to Globals
882///
883/// Globals are strong references to the window they are attached to, unless stored in a `Weak`
884/// reference (see the [`StrongHandle`] trait).
885/// This means that if you store a reference to a global, it will keep the entire window alive
886/// and prevent it from being dropped.
887///
888/// To make this less error-prone, when accessing a global from a window, it is initially bound to
889/// the lifetime of the Window it belongs to.
890/// This prevents you from accidentally capturing the global in a callback closure, which
891/// would result in the window never being dropped.
892///
893/// To store references to a global in a callback or Rust struct, you can convert it into
894/// a weak reference using the [`Global::as_weak`] function.
895/// This will also extend the lifetime of the global to `'static`.
896///
897/// Once the window is dropped, upgrading the weak reference will return `None`.
898///
899/// ## Example
900///
901/// ```rust
902/// # i_slint_backend_testing::init_no_event_loop();
903/// slint::slint!{
904/// export global Palette {
905/// in property<color> foreground-color;
906/// in property<color> background-color;
907/// }
908///
909/// export component App inherits Window {
910/// background: Palette.background-color;
911/// // ...
912/// }
913/// }
914///
915/// struct PaletteBackend {
916/// global: slint::Weak<Palette<'static>>,
917/// }
918///
919/// impl PaletteBackend {
920/// fn global(&self) -> Palette<'static> {
921/// self.global.upgrade().expect("The window was dropped, the global is no longer available")
922/// }
923/// }
924///
925/// let app = App::new().unwrap();
926///
927/// let palette_backend = PaletteBackend { global: app.global::<Palette>().as_weak() };
928/// ```
929pub trait Global<'a, Component> {
930 /// The `Self` type, with a `'static` lifetime.
931 type StaticSelf: 'static + StrongHandle;
932
933 /// Returns a reference to the global.
934 fn get(component: &'a Component) -> Self;
935
936 /// Convert this Global reference into a weak reference.
937 ///
938 /// This will also extend the lifetime of this global to `'static`, to allow storing
939 /// the Weak reference in a struct that does not have a lifetime itself.
940 fn as_weak(&self) -> Weak<Self::StaticSelf>;
941}
942
943/// This trait marks types that hold a strong reference to a Slint component.
944///
945/// The Slint compiler automatically implements this trait for [generated components](index.html#generated-components) and the `'static` variant of [generated Globals](index.html#exported-global-singletons).
946/// Do not try to implement it manually.
947///
948/// All types that implement this trait can be used in a [`Weak`] reference.
949///
950/// > ⚠️ Strong references should not be captured by a lambda given to a callback,
951/// > as this would produce a reference loop and leak the component.
952/// > Instead, the callback function should capture a [`Weak`] reference.
953///
954/// **Example:**
955/// ```
956/// # i_slint_backend_testing::init_no_event_loop();
957/// slint::slint!{
958/// export component App inherits Window {
959/// in-out property <int> counter: 0;
960/// callback do_something;
961/// }
962/// }
963///
964/// let app = App::new().unwrap();
965/// // ⚠️ Incorrect: This will capture a strong reference to the app in the closure,
966/// // which will never be released and leak the app!
967/// app.on_do_something({
968/// let app = app.clone_strong();
969/// move || {
970/// app.set_counter(app.get_counter() + 1);
971/// }
972/// });
973///
974/// // Correct: Use a weak reference to the app, which will be released
975/// // when the app is dropped.
976/// app.on_do_something({
977/// let app = app.as_weak();
978/// move || {
979/// let Some(app) = app.upgrade() else {
980/// return;
981/// };
982/// app.set_counter(app.get_counter() + 1);
983/// }
984/// });
985/// ```
986///
987/// # Common issues
988///
989/// To use a global with a [`Weak`] reference, you need to use the `'static` variant of the Global.
990///
991/// **Example:**
992/// ```
993/// # i_slint_backend_testing::init_no_event_loop();
994/// slint::slint!{
995/// export global MyGlobal {}
996///
997/// export component App inherits Window {}
998/// }
999/// struct MyStruct {
1000/// // Use the 'static variant of MyGlobal, which implements
1001/// // StrongHandle and can be used in a Weak reference.
1002/// global: slint::Weak<MyGlobal<'static>>,
1003/// }
1004///
1005/// let app = App::new().unwrap();
1006/// let my_global: MyGlobal = app.global();
1007///
1008/// let my_struct = MyStruct {
1009/// // Calling as_weak() on the global automatically converts it to 'static
1010/// global: my_global.as_weak()
1011/// };
1012/// ```
1013///
1014/// Otherwise you may encounter issues like this:
1015///
1016/// ```text
1017/// error[E0106]: missing lifetime specifier
1018/// --> /path/to/file.rs:10:19
1019/// |
1020/// 10 | global: Weak<MyGlobal>,
1021/// | ^^^^^^^^ expected named lifetime parameter
1022/// |
1023/// help: consider introducing a named lifetime parameter
1024/// |
1025/// 9 ~ struct MyStruct<'a> {
1026/// 10 ~ global: Weak<MyGlobal<'a>>,
1027/// ```
1028///
1029/// The compiler suggests to introduce a lifetime parameter for the struct,
1030/// This is not correct - use a `'static` lifetime instead!
1031///
1032/// Otherwise you will run into the following error:
1033///
1034/// ```text
1035/// error: incompatible lifetime on type
1036/// --> /path/to/file.rs:9:10
1037/// |
1038/// 9 | global: slint::Weak<MyGlobal<'a>>,
1039/// | ^^^^^^^^^^^^^^^^^^^^^^^^^
1040/// |
1041///note: because this has an unmet lifetime requirement
1042/// --> slint/internal/core/api.rs:954:24
1043/// |
1044///954 | pub struct Weak<T: StrongHandle> {
1045/// | ^^^^^^^^^^^^ introduces a `'static` lifetime requirement
1046///note: the lifetime `'a` as defined here...
1047/// --> /path/to/file.rs:8:17
1048/// |
1049/// 8 | struct MyStruct<'a> {
1050/// | ^^
1051///note: ...does not necessarily outlive the static lifetime introduced by the compatible `impl`
1052/// --> /path/to/file.rs:246:6
1053/// |
1054///246 | impl slint :: StrongHandle for r#MyGlobal < 'static > {
1055/// ```
1056pub trait StrongHandle {
1057 /// The internal Inner type for `Weak<Self>::inner`.
1058 #[doc(hidden)]
1059 type WeakInner: Clone + Default;
1060
1061 /// Internal function used when upgrading a weak reference to a strong one.
1062 #[doc(hidden)]
1063 fn upgrade_from_weak_inner(_: &Self::WeakInner) -> Option<Self>
1064 where
1065 Self: Sized;
1066}
1067
1068/// This trait describes the common public API of a strongly referenced Slint component.
1069/// It allows creating strongly-referenced clones, a conversion into a weak pointer as well
1070/// as other convenience functions.
1071///
1072/// This trait is implemented by the [generated component](index.html#generated-components)
1073pub trait ComponentHandle: StrongHandle {
1074 /// Returns a new weak pointer.
1075 // Note: It would be great if we could move this function into the StrongHandle trait. But
1076 // that would be a backwards-incompatible change.
1077 fn as_weak(&self) -> Weak<Self>
1078 where
1079 Self: Sized;
1080
1081 /// Returns a clone of this handle that's a strong reference.
1082 #[must_use]
1083 fn clone_strong(&self) -> Self;
1084
1085 /// Convenience function for [`crate::Window::show()`](struct.Window.html#method.show).
1086 /// This shows the window on the screen and maintains an extra strong reference while
1087 /// the window is visible. To react to events from the windowing system, such as draw
1088 /// requests or mouse/touch input, it is still necessary to spin the event loop,
1089 /// using [`crate::run_event_loop`](fn.run_event_loop.html).
1090 fn show(&self) -> Result<(), PlatformError>;
1091
1092 /// Convenience function for [`crate::Window::hide()`](struct.Window.html#method.hide).
1093 /// Hides the window, so that it is not visible anymore. The additional strong reference
1094 /// on the associated component, that was created when show() was called, is dropped.
1095 fn hide(&self) -> Result<(), PlatformError>;
1096
1097 /// Returns the Window associated with this component. The window API can be used
1098 /// to control different aspects of the integration into the windowing system,
1099 /// such as the position on the screen.
1100 fn window(&self) -> &Window;
1101
1102 /// This is a convenience function that first calls [`Self::show`], followed by [`crate::run_event_loop()`](fn.run_event_loop.html)
1103 /// and [`Self::hide`].
1104 fn run(&self) -> Result<(), PlatformError>;
1105
1106 /// This function provides access to instances of global singletons exported in `.slint`.
1107 /// See [`Global`] for an example how to export and access globals from `.slint` markup.
1108 fn global<'a, T: Global<'a, Self>>(&'a self) -> T
1109 where
1110 Self: Sized;
1111}
1112
1113mod weak_handle {
1114
1115 use super::*;
1116
1117 /// Struct that's used to hold weak references of a [Slint component or global](index.html#generated-components)
1118 ///
1119 /// In order to create a Weak, you should use [`ComponentHandle::as_weak`] or
1120 /// [`Global::as_weak`].
1121 ///
1122 /// Strong references should not be captured by the functions given to a lambda,
1123 /// as this would produce a reference loop and leak the component.
1124 /// Instead, the callback function should capture a weak component.
1125 ///
1126 /// The Weak component also implement `Send` and can be send to another thread.
1127 /// but the upgrade function will only return a valid component from the same thread
1128 /// as the one it has been created from.
1129 /// This is useful to use with [`invoke_from_event_loop()`] or [`Self::upgrade_in_event_loop()`].
1130 pub struct Weak<T: StrongHandle> {
1131 inner: T::WeakInner,
1132 #[cfg(feature = "std")]
1133 thread: std::thread::ThreadId,
1134 }
1135
1136 impl<T: StrongHandle> Default for Weak<T> {
1137 fn default() -> Self {
1138 Self {
1139 inner: T::WeakInner::default(),
1140 #[cfg(feature = "std")]
1141 thread: std::thread::current().id(),
1142 }
1143 }
1144 }
1145
1146 impl<T: StrongHandle> Clone for Weak<T> {
1147 fn clone(&self) -> Self {
1148 Self {
1149 inner: self.inner.clone(),
1150 #[cfg(feature = "std")]
1151 thread: self.thread,
1152 }
1153 }
1154 }
1155
1156 impl<T: StrongHandle> Weak<T> {
1157 #[doc(hidden)]
1158 pub fn new(inner: T::WeakInner) -> Self {
1159 Self {
1160 inner,
1161 #[cfg(feature = "std")]
1162 thread: std::thread::current().id(),
1163 }
1164 }
1165
1166 /// Returns a new strongly referenced component if some other instance still
1167 /// holds a strong reference. Otherwise, returns None.
1168 ///
1169 /// This also returns None if the current thread is not the thread that created
1170 /// the component
1171 pub fn upgrade(&self) -> Option<T> {
1172 #[cfg(feature = "std")]
1173 if std::thread::current().id() != self.thread {
1174 return None;
1175 }
1176 T::upgrade_from_weak_inner(&self.inner)
1177 }
1178
1179 /// Convenience function that returns a new strongly referenced component if
1180 /// some other instance still holds a strong reference and the current thread
1181 /// is the thread that created this component.
1182 /// Otherwise, this function panics.
1183 #[track_caller]
1184 pub fn unwrap(&self) -> T {
1185 #[cfg(feature = "std")]
1186 if std::thread::current().id() != self.thread {
1187 panic!(
1188 "Trying to upgrade a Weak from a different thread than the one it belongs to"
1189 );
1190 }
1191 T::upgrade_from_weak_inner(&self.inner)
1192 .expect("The Weak doesn't hold a valid component")
1193 }
1194
1195 /// A helper function to allow creation on `component_factory::Component` from
1196 /// a `ComponentHandle`
1197 pub(crate) fn inner(&self) -> T::WeakInner {
1198 self.inner.clone()
1199 }
1200
1201 /// Convenience function that combines [`invoke_from_event_loop()`] with [`Self::upgrade()`]
1202 ///
1203 /// The given functor will be added to an internal queue and will wake the event loop.
1204 /// On the next iteration of the event loop, the functor will be executed with a `T` as an argument.
1205 ///
1206 /// If the component was dropped because there are no more strong reference to the component,
1207 /// the functor will not be called.
1208 ///
1209 /// # Example
1210 /// ```rust
1211 /// # i_slint_backend_testing::init_no_event_loop();
1212 /// slint::slint! { export component MyApp inherits Window { in property <int> foo; /* ... */ } }
1213 /// let handle = MyApp::new().unwrap();
1214 /// let handle_weak = handle.as_weak();
1215 /// let thread = std::thread::spawn(move || {
1216 /// // ... Do some computation in the thread
1217 /// let foo = 42;
1218 /// # assert!(handle_weak.upgrade().is_none()); // note that upgrade fails in a thread
1219 /// # return; // don't upgrade_in_event_loop in our examples
1220 /// // now forward the data to the main thread using upgrade_in_event_loop
1221 /// handle_weak.upgrade_in_event_loop(move |handle| handle.set_foo(foo));
1222 /// });
1223 /// # thread.join().unwrap(); return; // don't run the event loop in examples
1224 /// handle.run().unwrap();
1225 /// ```
1226 #[cfg(any(feature = "std", feature = "unsafe-single-threaded"))]
1227 pub fn upgrade_in_event_loop(
1228 &self,
1229 func: impl FnOnce(T) + Send + 'static,
1230 ) -> Result<(), EventLoopError>
1231 where
1232 T: 'static,
1233 {
1234 let weak_handle = self.clone();
1235 super::invoke_from_event_loop(move || {
1236 if let Some(h) = weak_handle.upgrade() {
1237 func(h);
1238 }
1239 })
1240 }
1241 }
1242
1243 // Safety: we make sure in upgrade that the thread is the proper one,
1244 // and the VWeak only use atomic pointer so it is safe to clone and drop in another thread
1245 #[allow(unsafe_code)]
1246 #[cfg(any(feature = "std", feature = "unsafe-single-threaded"))]
1247 unsafe impl<T: StrongHandle> Send for Weak<T> {}
1248 #[allow(unsafe_code)]
1249 #[cfg(any(feature = "std", feature = "unsafe-single-threaded"))]
1250 unsafe impl<T: StrongHandle> Sync for Weak<T> {}
1251}
1252
1253pub use weak_handle::*;
1254
1255/// Adds the specified function to an internal queue, notifies the event loop to wake up.
1256/// Once woken up, any queued up functions will be invoked.
1257///
1258/// This function is thread-safe and can be called from any thread, including the one
1259/// running the event loop. The provided functions will only be invoked from the thread
1260/// that started the event loop.
1261///
1262/// You can use this to set properties or use any other Slint APIs from other threads,
1263/// by collecting the code in a functor and queuing it up for invocation within the event loop.
1264///
1265/// If you want to capture non-Send types to run in the next event loop iteration,
1266/// you can use the `slint::spawn_local` function instead.
1267///
1268/// See also [`Weak::upgrade_in_event_loop`].
1269///
1270/// # Example
1271/// ```rust
1272/// slint::slint! { export component MyApp inherits Window { in property <int> foo; /* ... */ } }
1273/// # i_slint_backend_testing::init_no_event_loop();
1274/// let handle = MyApp::new().unwrap();
1275/// let handle_weak = handle.as_weak();
1276/// # return; // don't run the event loop in examples
1277/// let thread = std::thread::spawn(move || {
1278/// // ... Do some computation in the thread
1279/// let foo = 42;
1280/// // now forward the data to the main thread using invoke_from_event_loop
1281/// let handle_copy = handle_weak.clone();
1282/// slint::invoke_from_event_loop(move || handle_copy.unwrap().set_foo(foo));
1283/// });
1284/// handle.run().unwrap();
1285/// ```
1286pub fn invoke_from_event_loop(func: impl FnOnce() + Send + 'static) -> Result<(), EventLoopError> {
1287 crate::platform::with_event_loop_proxy(|proxy| {
1288 proxy
1289 .ok_or(EventLoopError::NoEventLoopProvider)?
1290 .invoke_from_event_loop(alloc::boxed::Box::new(func))
1291 })
1292}
1293
1294/// Schedules the main event loop for termination. This function is meant
1295/// to be called from callbacks triggered by the UI. After calling the function,
1296/// it will return immediately and once control is passed back to the event loop,
1297/// the initial call to `slint::run_event_loop()` will return.
1298///
1299/// This function can be called from any thread
1300///
1301/// Any previously queued events may or may not be processed before the loop terminates.
1302/// This is platform dependent behavior.
1303pub fn quit_event_loop() -> Result<(), EventLoopError> {
1304 crate::platform::with_event_loop_proxy(|proxy| {
1305 proxy.ok_or(EventLoopError::NoEventLoopProvider)?.quit_event_loop()
1306 })
1307}
1308
1309#[derive(Debug, Clone, Eq, PartialEq)]
1310#[non_exhaustive]
1311/// Error returned from the [`invoke_from_event_loop()`] and [`quit_event_loop()`] function
1312pub enum EventLoopError {
1313 /// The event could not be sent because the event loop was terminated already
1314 EventLoopTerminated,
1315 /// The event could not be sent because the Slint platform abstraction was not yet initialized,
1316 /// or the platform does not support event loop.
1317 NoEventLoopProvider,
1318}
1319
1320impl core::fmt::Display for EventLoopError {
1321 fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
1322 match self {
1323 EventLoopError::EventLoopTerminated => {
1324 f.write_str("The event loop was already terminated")
1325 }
1326 EventLoopError::NoEventLoopProvider => {
1327 f.write_str("The Slint platform does not provide an event loop")
1328 }
1329 }
1330 }
1331}
1332
1333#[cfg(feature = "std")]
1334impl std::error::Error for EventLoopError {}
1335
1336/// The platform encountered a fatal error.
1337///
1338/// This error typically indicates an issue with initialization or connecting to the windowing system.
1339///
1340/// This can be constructed from a `String`:
1341/// ```rust
1342/// use slint::platform::PlatformError;
1343/// PlatformError::from(format!("Could not load resource {}", 1234));
1344/// ```
1345#[non_exhaustive]
1346pub enum PlatformError {
1347 /// No default platform was selected, or no platform could be initialized.
1348 ///
1349 /// If you encounter this error, make sure to either selected trough the `backend-*` cargo features flags,
1350 /// or call [`platform::set_platform()`](crate::platform::set_platform)
1351 /// before running the event loop
1352 NoPlatform,
1353
1354 /// The Slint Platform does not provide an event loop.
1355 ///
1356 /// The [`Platform::run_event_loop`](crate::platform::Platform::run_event_loop)
1357 /// is not implemented for the current platform.
1358 NoEventLoopProvider,
1359
1360 /// There is already a platform set from another thread.
1361 SetPlatformError(crate::platform::SetPlatformError),
1362
1363 /// The operation is not supported by the current platform.
1364 Unsupported,
1365
1366 /// Another platform-specific error occurred
1367 Other(String),
1368
1369 /// Another platform-specific error occurred.
1370 OtherError(Box<dyn core::error::Error + Send + Sync>),
1371}
1372
1373#[cfg(target_arch = "wasm32")]
1374impl From<PlatformError> for wasm_bindgen::JsValue {
1375 fn from(err: PlatformError) -> wasm_bindgen::JsValue {
1376 wasm_bindgen::JsError::from(err).into()
1377 }
1378}
1379
1380impl core::fmt::Debug for PlatformError {
1381 fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
1382 core::fmt::Display::fmt(self, f)
1383 }
1384}
1385
1386impl core::fmt::Display for PlatformError {
1387 fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
1388 match self {
1389 PlatformError::NoPlatform => f.write_str(
1390 "No default Slint platform was selected, and no Slint platform was initialized",
1391 ),
1392 PlatformError::NoEventLoopProvider => {
1393 f.write_str("The Slint platform does not provide an event loop")
1394 }
1395 PlatformError::SetPlatformError(_) => {
1396 f.write_str("The Slint platform was initialized in another thread")
1397 }
1398 PlatformError::Unsupported => {
1399 f.write_str("The operation is not supported by the current platform")
1400 }
1401 PlatformError::Other(str) => f.write_str(str),
1402 PlatformError::OtherError(error) => error.fmt(f),
1403 }
1404 }
1405}
1406
1407impl From<String> for PlatformError {
1408 fn from(value: String) -> Self {
1409 Self::Other(value)
1410 }
1411}
1412impl From<&str> for PlatformError {
1413 fn from(value: &str) -> Self {
1414 Self::Other(value.into())
1415 }
1416}
1417
1418#[cfg(feature = "std")]
1419impl From<Box<dyn std::error::Error + Send + Sync>> for PlatformError {
1420 fn from(error: Box<dyn std::error::Error + Send + Sync>) -> Self {
1421 Self::OtherError(error)
1422 }
1423}
1424
1425#[cfg(feature = "std")]
1426impl std::error::Error for PlatformError {
1427 fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
1428 match self {
1429 PlatformError::OtherError(err) => Some(err.as_ref()),
1430 _ => None,
1431 }
1432 }
1433}
1434
1435#[test]
1436#[cfg(feature = "std")]
1437fn error_is_send() {
1438 let _: Box<dyn std::error::Error + Send + Sync + 'static> = PlatformError::NoPlatform.into();
1439}
1440
1441/// Sets the application id for use on Wayland or X11 with [xdg](https://specifications.freedesktop.org/desktop-entry-spec/latest/)
1442/// compliant window managers. This must be set before the window is shown, and has only an effect on Wayland or X11.
1443pub fn set_xdg_app_id(app_id: impl Into<SharedString>) -> Result<(), PlatformError> {
1444 crate::context::with_global_context(
1445 || Err(crate::platform::PlatformError::NoPlatform),
1446 |ctx| ctx.set_xdg_app_id(app_id.into()),
1447 )
1448}