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// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License in the LICENSE-APACHE file or at:
// https://www.apache.org/licenses/LICENSE-2.0
//! Event manager — public API
use std::fmt::Debug;
use std::future::IntoFuture;
use std::time::{Duration, Instant};
use super::*;
use crate::cast::Conv;
use crate::draw::DrawShared;
use crate::event::config::ChangeConfig;
use crate::geom::{Offset, Vec2};
use crate::theme::{SizeCx, ThemeControl};
#[cfg(all(wayland_platform, feature = "clipboard"))]
use crate::util::warn_about_error;
use crate::{messages::Erased, Action, HasId, Id, Window, WindowId};
#[allow(unused)] use crate::{Events, Layout}; // for doc-links
/// Public API
impl EventState {
/// Get the platform
pub fn platform(&self) -> Platform {
self.platform
}
/// True when the window has focus
#[inline]
pub fn window_has_focus(&self) -> bool {
self.window_has_focus
}
/// True when access key labels should be shown
///
/// (True when Alt is held and no widget has character focus.)
///
/// This is a fast check.
#[inline]
pub fn show_access_labels(&self) -> bool {
self.modifiers.alt_key()
}
/// Get whether this widget has `(key_focus, sel_focus)`
///
/// - `key_focus`: implies this widget receives keyboard input
/// - `sel_focus`: implies this widget is allowed to select things
///
/// Note that `key_focus` implies `sel_focus`.
#[inline]
pub fn has_key_focus(&self, w_id: &Id) -> (bool, bool) {
let sel_focus = *w_id == self.sel_focus;
(sel_focus && self.key_focus, sel_focus)
}
/// Get whether this widget has navigation focus
#[inline]
pub fn has_nav_focus(&self, w_id: &Id) -> bool {
*w_id == self.nav_focus
}
/// Get whether the widget is under the mouse cursor
#[inline]
pub fn is_hovered(&self, w_id: &Id) -> bool {
self.mouse_grab.is_none() && *w_id == self.hover
}
/// Get whether widget `id` or any of its descendants are under the mouse cursor
#[inline]
pub fn is_hovered_recursive(&self, id: &Id) -> bool {
self.mouse_grab.is_none()
&& self
.hover
.as_ref()
.map(|h| id.is_ancestor_of(h))
.unwrap_or(false)
}
/// Check whether the given widget is visually depressed
pub fn is_depressed(&self, w_id: &Id) -> bool {
for (_, id) in &self.key_depress {
if *id == w_id {
return true;
}
}
if self
.mouse_grab
.as_ref()
.map(|grab| *w_id == grab.depress)
.unwrap_or(false)
{
return true;
}
for grab in self.touch_grab.iter() {
if *w_id == grab.depress {
return true;
}
}
for popup in &self.popups {
if *w_id == popup.1.parent {
return true;
}
}
false
}
/// Check whether a widget is disabled
///
/// A widget is disabled if any ancestor is.
#[inline]
pub fn is_disabled(&self, w_id: &Id) -> bool {
// TODO(opt): we should be able to use binary search here
for id in &self.disabled {
if id.is_ancestor_of(w_id) {
return true;
}
}
false
}
/// Get the current modifier state
#[inline]
pub fn modifiers(&self) -> ModifiersState {
self.modifiers
}
/// Access event-handling configuration
#[inline]
pub fn config(&self) -> &WindowConfig {
&self.config
}
/// Is mouse panning enabled?
#[inline]
pub fn config_enable_pan(&self, source: PressSource) -> bool {
source.is_touch()
|| source.is_primary() && self.config.mouse_pan().is_enabled_with(self.modifiers())
}
/// Is mouse text panning enabled?
#[inline]
pub fn config_enable_mouse_text_pan(&self) -> bool {
self.config
.mouse_text_pan()
.is_enabled_with(self.modifiers())
}
/// Test pan threshold against config, adjusted for scale factor
///
/// Returns true when `dist` is large enough to switch to pan mode.
#[inline]
pub fn config_test_pan_thresh(&self, dist: Offset) -> bool {
Vec2::conv(dist).abs().max_comp() >= self.config.pan_dist_thresh()
}
/// Update event configuration
#[inline]
pub fn change_config(&mut self, msg: ChangeConfig) {
match self.config.config.try_borrow_mut() {
Ok(mut config) => {
config.change_config(msg);
self.action |= Action::EVENT_CONFIG;
}
Err(_) => log::error!("EventState::change_config: failed to mutably borrow config"),
}
}
/// Set/unset a widget as disabled
///
/// Disabled status applies to all descendants and blocks reception of
/// events ([`Unused`] is returned automatically when the
/// recipient or any ancestor is disabled).
pub fn set_disabled(&mut self, w_id: Id, state: bool) {
for (i, id) in self.disabled.iter().enumerate() {
if w_id == id {
if !state {
self.redraw(w_id);
self.disabled.remove(i);
}
return;
}
}
if state {
self.action(&w_id, Action::REDRAW);
self.disabled.push(w_id);
}
}
/// Schedule a timed update
///
/// Widget updates may be used for animation and timed responses. See also
/// [`Draw::animate`](crate::draw::Draw::animate) for animation.
///
/// Widget `id` will receive [`Event::Timer`] with this `payload` at
/// approximately `time = now + delay` (or possibly a little later due to
/// frame-rate limiters and processing time).
///
/// Requesting an update with `delay == 0` is valid, except from an
/// [`Event::Timer`] handler (where it may cause an infinite loop).
///
/// Multiple timer requests with the same `id` and `payload` are merged
/// (choosing the earliest time).
pub fn request_timer(&mut self, id: Id, payload: u64, delay: Duration) {
let time = Instant::now() + delay;
if let Some(row) = self
.time_updates
.iter_mut()
.find(|row| row.1 == id && row.2 == payload)
{
if row.0 <= time {
return;
}
row.0 = time;
log::trace!(
target: "kas_core::event",
"request_timer: update {id} at now+{}ms",
delay.as_millis()
);
} else {
self.time_updates.push((time, id, payload));
}
self.time_updates.sort_by(|a, b| b.0.cmp(&a.0)); // reverse sort
}
/// Notify that a widget must be redrawn
///
/// This is equivalent to calling [`Self::action`] with [`Action::REDRAW`].
#[inline]
pub fn redraw(&mut self, id: impl HasId) {
self.action(id, Action::REDRAW);
}
/// Notify that a widget must be resized
///
/// This is equivalent to calling [`Self::action`] with [`Action::RESIZE`].
#[inline]
pub fn resize(&mut self, id: impl HasId) {
self.action(id, Action::RESIZE);
}
/// Notify that widgets under self may have moved
#[inline]
pub fn region_moved(&mut self) {
// Do not take id: this always applies to the whole window
self.action |= Action::REGION_MOVED;
}
/// Terminate the GUI
#[inline]
pub fn exit(&mut self) {
self.action |= Action::EXIT;
}
/// Notify that a [`Action`] action should happen
///
/// This causes the given action to happen after event handling.
///
/// Whenever a widget is added, removed or replaced, a reconfigure action is
/// required. Should a widget's size requirements change, these will only
/// affect the UI after a reconfigure action.
#[inline]
pub fn action(&mut self, id: impl HasId, action: Action) {
fn inner(cx: &mut EventState, id: Id, mut action: Action) {
const RE_UP: Action = Action::RECONFIGURE.union(Action::UPDATE);
if !(action & RE_UP).is_empty() {
cx.request_update(id, action.contains(Action::RECONFIGURE));
action.remove(RE_UP);
}
// TODO(opt): handle sub-tree SET_RECT and RESIZE.
// NOTE: our draw system is incompatible with partial redraws, and
// in any case redrawing is extremely fast.
cx.action |= action;
}
inner(self, id.has_id(), action)
}
/// Pass an [action](Self::action) given some `id`
#[inline]
pub(crate) fn opt_action(&mut self, id: Option<Id>, action: Action) {
if let Some(id) = id {
self.action(id, action);
}
}
/// Attempts to set a fallback to receive [`Event::Command`]
///
/// In case a navigation key is pressed (see [`Command`]) but no widget has
/// navigation focus, then, if a fallback has been set, that widget will
/// receive the key via [`Event::Command`].
///
/// Only one widget can be a fallback, and the *first* to set itself wins.
/// This is primarily used to allow scroll-region widgets to
/// respond to navigation keys when no widget has focus.
pub fn register_nav_fallback(&mut self, id: Id) {
if self.nav_fallback.is_none() {
log::debug!(target: "kas_core::event","register_nav_fallback: id={id}");
self.nav_fallback = Some(id);
}
}
fn access_layer_for_id(&mut self, id: &Id) -> Option<&mut AccessLayer> {
let root = &Id::ROOT;
for (k, v) in self.access_layers.range_mut(root..=id).rev() {
if k.is_ancestor_of(id) {
return Some(v);
};
}
debug_assert!(false, "expected ROOT access layer");
None
}
/// Add a new access key layer
///
/// This method constructs a new "layer" for access keys: any keys
/// added via [`EventState::add_access_key`] to a widget which is a descentant
/// of (or equal to) `id` will only be active when that layer is active.
///
/// This method should only be called by parents of a pop-up: layers over
/// the base layer are *only* activated by an open pop-up.
///
/// If `alt_bypass` is true, then this layer's access keys will be
/// active even without Alt pressed (but only highlighted with Alt pressed).
pub fn new_access_layer(&mut self, id: Id, alt_bypass: bool) {
self.access_layers.insert(id, (alt_bypass, HashMap::new()));
}
/// Enable `alt_bypass` for layer
///
/// This may be called by a child widget during configure to enable or
/// disable alt-bypass for the access-key layer containing its access keys.
/// This allows access keys to be used as shortcuts without the Alt
/// key held. See also [`EventState::new_access_layer`].
pub fn enable_alt_bypass(&mut self, id: &Id, alt_bypass: bool) {
if let Some(layer) = self.access_layer_for_id(id) {
layer.0 = alt_bypass;
}
}
/// Adds an access key for a widget
///
/// An *access key* (also known as mnemonic) is a shortcut key able to
/// directly open menus,
/// activate buttons, etc. A user triggers the key by pressing `Alt+Key`,
/// or (if `alt_bypass` is enabled) by simply pressing the key.
/// The widget with this `id` then receives [`Command::Activate`].
///
/// Note that access keys may be automatically derived from labels:
/// see [`crate::text::AccessString`].
///
/// Access keys are added to the layer with the longest path which is
/// an ancestor of `id`. This usually means that if the widget is part of a
/// pop-up, the key is only active when that pop-up is open.
/// See [`EventState::new_access_layer`].
///
/// This should only be called from [`Events::configure`].
#[inline]
pub fn add_access_key(&mut self, id: &Id, key: Key) {
if let Some(layer) = self.access_layer_for_id(id) {
layer.1.entry(key).or_insert_with(|| id.clone());
}
}
/// Visually depress a widget via a key code
///
/// When a button-like widget is activated by a key it may call this to
/// ensure the widget is visually depressed until the key is released.
/// The widget will not receive a notification of key-release but will be
/// redrawn automatically.
///
/// Note that keyboard shortcuts and mnemonics should usually match against
/// the "logical key". [`PhysicalKey`] is used here since the the logical key
/// may be changed by modifier keys.
pub fn depress_with_key(&mut self, id: Id, code: PhysicalKey) {
if self.key_depress.values().any(|v| *v == id) {
return;
}
self.key_depress.insert(code, id.clone());
self.action(id, Action::REDRAW);
}
/// Request keyboard input focus
///
/// When granted, the widget will receive [`Event::KeyFocus`] followed by
/// [`Event::Key`] for each key press / release. Note that this disables
/// translation of key events to [`Event::Command`] while key focus is
/// active.
///
/// The `source` parameter is used by [`Event::SelFocus`].
///
/// Key focus implies sel focus (see [`Self::request_sel_focus`]) and
/// navigation focus.
#[inline]
pub fn request_key_focus(&mut self, target: Id, source: FocusSource) {
self.pending_sel_focus = Some(PendingSelFocus {
target: Some(target),
key_focus: true,
source,
});
}
/// Request selection focus
///
/// To prevent multiple simultaneous selections (e.g. of text) in the UI,
/// only widgets with "selection focus" are allowed to select things.
/// Selection focus is implied by character focus. [`Event::LostSelFocus`]
/// is sent when selection focus is lost; in this case any existing
/// selection should be cleared.
///
/// The `source` parameter is used by [`Event::SelFocus`].
///
/// Selection focus implies navigation focus.
///
/// When key focus is lost, [`Event::LostSelFocus`] is sent.
#[inline]
pub fn request_sel_focus(&mut self, target: Id, source: FocusSource) {
if let Some(ref pending) = self.pending_sel_focus {
if pending.target.as_ref() == Some(&target) {
return;
}
}
self.pending_sel_focus = Some(PendingSelFocus {
target: Some(target),
key_focus: false,
source,
});
}
/// Set a grab's depress target
///
/// When a grab on mouse or touch input is in effect
/// ([`Press::grab`]), the widget owning the grab may set itself
/// or any other widget as *depressed* ("pushed down"). Each grab depresses
/// at most one widget, thus setting a new depress target clears any
/// existing target. Initially a grab depresses its owner.
///
/// This effect is purely visual. A widget is depressed when one or more
/// grabs targets the widget to depress, or when a keyboard binding is used
/// to activate a widget (for the duration of the key-press).
///
/// Queues a redraw and returns `true` if the depress target changes,
/// otherwise returns `false`.
pub fn set_grab_depress(&mut self, source: PressSource, target: Option<Id>) -> bool {
let mut old = None;
let mut redraw = false;
match source {
PressSource::Mouse(_, _) => {
if let Some(grab) = self.mouse_grab.as_mut() {
redraw = grab.depress != target;
old = grab.depress.take();
grab.depress = target.clone();
}
}
PressSource::Touch(id) => {
if let Some(grab) = self.get_touch(id) {
redraw = grab.depress != target;
old = grab.depress.take();
grab.depress = target.clone();
}
}
}
if redraw {
log::trace!(target: "kas_core::event", "set_grab_depress: target={target:?}");
self.opt_action(old, Action::REDRAW);
self.opt_action(target, Action::REDRAW);
}
redraw
}
/// Returns true if `id` or any descendant has a mouse or touch grab
pub fn any_pin_on(&self, id: &Id) -> bool {
if self
.mouse_grab
.as_ref()
.map(|grab| grab.start_id == id)
.unwrap_or(false)
{
return true;
}
if self.touch_grab.iter().any(|grab| grab.start_id == id) {
return true;
}
false
}
/// Get the current navigation focus, if any
///
/// This is the widget selected by navigating the UI with the Tab key.
///
/// Note: changing navigation focus (e.g. via [`Self::clear_nav_focus`],
/// [`Self::set_nav_focus`] or [`Self::next_nav_focus`]) does not
/// immediately affect the result of this method.
#[inline]
pub fn nav_focus(&self) -> Option<&Id> {
self.nav_focus.as_ref()
}
/// Clear navigation focus
pub fn clear_nav_focus(&mut self) {
self.pending_nav_focus = PendingNavFocus::Set {
target: None,
source: FocusSource::Synthetic,
};
}
/// Set navigation focus directly
///
/// If `id` already has navigation focus or navigation focus is disabled
/// globally then nothing happens, otherwise widget `id` should receive
/// [`Event::NavFocus`].
///
/// Normally, [`Events::navigable`] will be true for widget `id` but this
/// is not checked or required. For example, a `ScrollLabel` can receive
/// focus on text selection with the mouse.
pub fn set_nav_focus(&mut self, id: Id, source: FocusSource) {
self.pending_nav_focus = PendingNavFocus::Set {
target: Some(id),
source,
};
}
/// Advance the navigation focus
///
/// If `target == Some(id)`, this looks for the next widget from `id`
/// (inclusive) which is navigable ([`Events::navigable`]). Otherwise where
/// some widget `id` has [`nav_focus`](Self::nav_focus) this looks for the
/// next navigable widget *excluding* `id`. If no reference is available,
/// this instead looks for the first navigable widget.
///
/// If `reverse`, instead search for the previous or last navigable widget.
pub fn next_nav_focus(
&mut self,
target: impl Into<Option<Id>>,
reverse: bool,
source: FocusSource,
) {
self.pending_nav_focus = PendingNavFocus::Next {
target: target.into(),
reverse,
source,
};
}
/// Set the cursor icon
///
/// This is normally called when handling [`Event::MouseHover`]. In other
/// cases, calling this method may be ineffective. The cursor is
/// automatically "unset" when the widget is no longer hovered.
///
/// See also [`EventCx::set_grab_cursor`]: if a mouse grab
/// ([`Press::grab`]) is active, its icon takes precedence.
pub fn set_hover_cursor(&mut self, icon: CursorIcon) {
// Note: this is acted on by EventState::update
self.hover_icon = icon;
}
/// Asynchronously push a message to the stack via a [`Future`]
///
/// The future is polled after event handling and after drawing and is able
/// to wake the event loop. This future is executed on the main thread; for
/// high-CPU tasks use [`Self::push_spawn`] instead.
///
/// The future must resolve to a message on completion. This message is
/// pushed to the message stack as if it were pushed with [`EventCx::push`]
/// from widget `id`, allowing this widget or any ancestor to handle it in
/// [`Events::handle_messages`].
pub fn push_async<Fut, M>(&mut self, id: Id, fut: Fut)
where
Fut: IntoFuture<Output = M> + 'static,
M: Debug + 'static,
{
self.push_async_erased(id, async { Erased::new(fut.await) });
}
/// Asynchronously push a type-erased message to the stack via a [`Future`]
///
/// This is a low-level variant of [`Self::push_async`].
pub fn push_async_erased<Fut>(&mut self, id: Id, fut: Fut)
where
Fut: IntoFuture<Output = Erased> + 'static,
{
let fut = Box::pin(fut.into_future());
self.fut_messages.push((id, fut));
}
/// Spawn a task, run on a thread pool
///
/// The future is spawned to a thread-pool before the event-handling loop
/// sleeps, and is able to wake the loop on completion. Tasks involving
/// significant CPU work should use this method over [`Self::push_async`].
///
/// This method is simply a wrapper around [`async_global_executor::spawn`]
/// and [`Self::push_async`]; if a different multi-threaded executor is
/// available, that may be used instead. See also [`async_global_executor`]
/// documentation of configuration.
#[cfg(feature = "spawn")]
#[cfg_attr(doc_cfg, doc(cfg(feature = "spawn")))]
pub fn push_spawn<Fut, M>(&mut self, id: Id, fut: Fut)
where
Fut: IntoFuture<Output = M> + 'static,
Fut::IntoFuture: Send,
M: Debug + Send + 'static,
{
self.push_async(id, async_global_executor::spawn(fut.into_future()));
}
/// Request update and optionally configure to widget `id`
///
/// If `reconf`, widget `id` will be [configured](Events::configure)
/// (includes update), otherwise `id` will only be [updated](Events::update).
pub fn request_update(&mut self, id: Id, reconf: bool) {
self.pending_update = if let Some((id2, rc2)) = self.pending_update.take() {
Some((id.common_ancestor(&id2), reconf || rc2))
} else {
Some((id, reconf))
};
}
}
/// Public API
impl<'a> EventCx<'a> {
/// Configure a widget
///
/// Note that, when handling events, this method returns the *old* state.
///
/// This is a shortcut to [`ConfigCx::configure`].
#[inline]
pub fn configure(&mut self, mut widget: Node<'_>, id: Id) {
widget._configure(&mut self.config_cx(), id);
}
/// Update a widget
///
/// [`Events::update`] will be called recursively on each child and finally
/// `self`. If a widget stores state which it passes to children as input
/// data, it should call this (or [`ConfigCx::update`]) after mutating the state.
#[inline]
pub fn update(&mut self, mut widget: Node<'_>) {
widget._update(&mut self.config_cx());
}
/// Get the index of the last child visited
///
/// This is only used when unwinding (traversing back up the widget tree),
/// and returns the index of the child last visited. E.g. when
/// [`Events::handle_messages`] is called, this method returns the index of
/// the child which submitted the message (or whose descendant did).
/// Otherwise this returns `None` (including when the widget itself is the
/// submitter of the message).
pub fn last_child(&self) -> Option<usize> {
self.last_child
}
/// Send a command to a widget
///
/// Sends [`Event::Command`] to widget `id`. The event is queued to send
/// later, thus any actions by the receiving widget will not be immediately
/// visible to the caller of this method.
///
/// When calling this method, be aware that some widgets use an inner
/// component to handle events, thus calling with the outer widget's `id`
/// may not have the desired effect. [`Layout::find_id`] and
/// [`EventState::next_nav_focus`] are usually able to find the appropriate
/// event-handling target.
pub fn send_command(&mut self, id: Id, cmd: Command) {
self.pending_cmds.push_back((id, cmd));
}
/// Push a message to the stack
///
/// The message is first type-erased by wrapping with [`Erased`],
/// then pushed to the stack.
///
/// The message may be [popped](EventCx::try_pop) or
/// [observed](EventCx::try_observe) from [`Events::handle_messages`]
/// by the widget itself, its parent, or any ancestor.
pub fn push<M: Debug + 'static>(&mut self, msg: M) {
self.push_erased(Erased::new(msg));
}
/// Push a type-erased message to the stack
///
/// This is a lower-level variant of [`Self::push`].
///
/// The message may be [popped](EventCx::try_pop) or
/// [observed](EventCx::try_observe) from [`Events::handle_messages`]
/// by the widget itself, its parent, or any ancestor.
pub fn push_erased(&mut self, msg: Erased) {
self.messages.push_erased(msg);
}
/// True if the message stack is non-empty
pub fn has_msg(&self) -> bool {
self.messages.has_any()
}
/// Try popping the last message from the stack with the given type
///
/// This method may be called from [`Events::handle_messages`].
pub fn try_pop<M: Debug + 'static>(&mut self) -> Option<M> {
self.messages.try_pop()
}
/// Try observing the last message on the stack without popping
///
/// This method may be called from [`Events::handle_messages`].
pub fn try_observe<M: Debug + 'static>(&self) -> Option<&M> {
self.messages.try_observe()
}
/// Set a scroll action
///
/// When setting [`Scroll::Rect`], use the widget's own coordinate space.
///
/// Note that calling this method has no effect on the widget itself, but
/// affects parents via their [`Events::handle_scroll`] method.
#[inline]
pub fn set_scroll(&mut self, scroll: Scroll) {
self.scroll = scroll;
}
/// Add an overlay (pop-up)
///
/// A pop-up is a box used for things like tool-tips and menus which is
/// drawn on top of other content and has focus for input.
///
/// Depending on the host environment, the pop-up may be a special type of
/// window without borders and with precise placement, or may be a layer
/// drawn in an existing window.
///
/// The popup automatically receives mouse-motion events
/// ([`Event::CursorMove`]) which may be used to navigate menus.
/// The parent automatically receives the "depressed" visual state.
///
/// It is recommended to call [`EventState::set_nav_focus`] or
/// [`EventState::next_nav_focus`] after this method.
///
/// A pop-up may be closed by calling [`EventCx::close_window`] with
/// the [`WindowId`] returned by this method.
pub(crate) fn add_popup(&mut self, popup: crate::PopupDescriptor) -> WindowId {
log::trace!(target: "kas_core::event", "add_popup: {popup:?}");
let parent_id = self.window.window_id();
let id = self.shared.add_popup(parent_id, popup.clone());
let nav_focus = self.nav_focus.clone();
self.popups.push((id, popup, nav_focus));
self.clear_nav_focus();
id
}
/// Add a window
///
/// Typically an application adds at least one window before the event-loop
/// starts (see `kas_wgpu::Toolkit::add`), however that method is not
/// available to a running UI. This method may be used instead.
///
/// Requirement: the type `Data` must match the type of data passed to the
/// [`Application`](crate::app::Application) and used by other windows.
/// If not, a run-time error will result.
///
/// Caveat: if an error occurs opening the new window it will not be
/// reported (except via log messages).
#[inline]
pub fn add_window<Data: 'static>(&mut self, window: Window<Data>) -> WindowId {
let data_type_id = std::any::TypeId::of::<Data>();
unsafe {
let window: Window<()> = std::mem::transmute(window);
self.shared.add_window(window, data_type_id)
}
}
/// Close a window or pop-up
///
/// Navigation focus will return to whichever widget had focus before
/// the popup was open.
pub fn close_window(&mut self, id: WindowId) {
if let Some(index) =
self.popups
.iter()
.enumerate()
.find_map(|(i, p)| if p.0 == id { Some(i) } else { None })
{
let (wid, popup, onf) = self.popups.remove(index);
self.popup_removed.push((popup.id, wid));
self.shared.close_window(wid);
if let Some(id) = onf {
self.set_nav_focus(id, FocusSource::Synthetic);
}
return;
}
self.shared.close_window(id);
}
/// Enable window dragging for current click
///
/// This calls [`winit::window::Window::drag_window`](https://docs.rs/winit/latest/winit/window/struct.Window.html#method.drag_window). Errors are ignored.
pub fn drag_window(&self) {
#[cfg(winit)]
if let Some(ww) = self.window.winit_window() {
if let Err(e) = ww.drag_window() {
log::warn!("EventCx::drag_window: {e}");
}
}
}
/// Enable window resizing for the current click
///
/// This calls [`winit::window::Window::drag_resize_window`](https://docs.rs/winit/latest/winit/window/struct.Window.html#method.drag_resize_window). Errors are ignored.
pub fn drag_resize_window(&self, direction: ResizeDirection) {
#[cfg(winit)]
if let Some(ww) = self.window.winit_window() {
if let Err(e) = ww.drag_resize_window(direction) {
log::warn!("EventCx::drag_resize_window: {e}");
}
}
}
/// Attempt to get clipboard contents
///
/// In case of failure, paste actions will simply fail. The implementation
/// may wish to log an appropriate warning message.
#[inline]
pub fn get_clipboard(&mut self) -> Option<String> {
#[cfg(all(wayland_platform, feature = "clipboard"))]
if let Some(cb) = self.window.wayland_clipboard() {
return match cb.load() {
Ok(s) => Some(s),
Err(e) => {
warn_about_error("Failed to get clipboard contents", &e);
None
}
};
}
self.shared.get_clipboard()
}
/// Attempt to set clipboard contents
#[inline]
pub fn set_clipboard(&mut self, content: String) {
#[cfg(all(wayland_platform, feature = "clipboard"))]
if let Some(cb) = self.window.wayland_clipboard() {
cb.store(content);
return;
}
self.shared.set_clipboard(content)
}
/// True if the primary buffer is enabled
#[inline]
pub fn has_primary(&self) -> bool {
cfg_if::cfg_if! {
if #[cfg(unix)] {
true
} else {
false
}
}
}
/// Get contents of primary buffer
///
/// Linux has a "primary buffer" with implicit copy on text selection and
/// paste on middle-click. This method does nothing on other platforms.
#[inline]
pub fn get_primary(&mut self) -> Option<String> {
#[cfg(all(wayland_platform, feature = "clipboard"))]
if let Some(cb) = self.window.wayland_clipboard() {
return match cb.load_primary() {
Ok(s) => Some(s),
Err(e) => {
warn_about_error("Failed to get clipboard contents", &e);
None
}
};
}
self.shared.get_primary()
}
/// Set contents of primary buffer
///
/// Linux has a "primary buffer" with implicit copy on text selection and
/// paste on middle-click. This method does nothing on other platforms.
#[inline]
pub fn set_primary(&mut self, content: String) {
#[cfg(all(wayland_platform, feature = "clipboard"))]
if let Some(cb) = self.window.wayland_clipboard() {
cb.store_primary(content);
return;
}
self.shared.set_primary(content)
}
/// Adjust the theme
#[inline]
pub fn adjust_theme<F: FnOnce(&mut dyn ThemeControl) -> Action>(&mut self, f: F) {
self.shared.adjust_theme(Box::new(f));
}
/// Get a [`SizeCx`]
///
/// Warning: sizes are calculated using the window's current scale factor.
/// This may change, even without user action, since some platforms
/// always initialize windows with scale factor 1.
/// See also notes on [`Events::configure`].
pub fn size_cx(&self) -> SizeCx<'_> {
SizeCx::new(self.window.theme_size())
}
/// Get a [`ConfigCx`]
pub fn config_cx(&mut self) -> ConfigCx<'_> {
let size = self.window.theme_size();
ConfigCx::new(size, self.state)
}
/// Get a [`DrawShared`]
pub fn draw_shared(&mut self) -> &mut dyn DrawShared {
self.shared.draw_shared()
}
/// Directly access Winit Window
///
/// This is a temporary API, allowing e.g. to minimize the window.
#[cfg(winit)]
pub fn winit_window(&self) -> Option<&winit::window::Window> {
self.window.winit_window()
}
/// Update the mouse cursor used during a grab
///
/// This only succeeds if widget `id` has an active mouse-grab (see
/// [`Press::grab`]). The cursor will be reset when the mouse-grab
/// ends.
pub fn set_grab_cursor(&mut self, id: &Id, icon: CursorIcon) {
if let Some(ref grab) = self.mouse_grab {
if grab.start_id == *id {
self.window.set_cursor_icon(icon);
}
}
}
}