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Diffstat (limited to 'runtime/src/multi_window/state.rs')
| -rw-r--r-- | runtime/src/multi_window/state.rs | 280 |
1 files changed, 280 insertions, 0 deletions
diff --git a/runtime/src/multi_window/state.rs b/runtime/src/multi_window/state.rs new file mode 100644 index 00000000..78c35e6c --- /dev/null +++ b/runtime/src/multi_window/state.rs @@ -0,0 +1,280 @@ +//! The internal state of a multi-window [`Program`]. +use crate::core::event::{self, Event}; +use crate::core::mouse; +use crate::core::renderer; +use crate::core::widget::operation::{self, Operation}; +use crate::core::{Clipboard, Size}; +use crate::user_interface::{self, UserInterface}; +use crate::{Command, Debug, Program}; + +/// The execution state of a multi-window [`Program`]. It leverages caching, event +/// processing, and rendering primitive storage. +#[allow(missing_debug_implementations)] +pub struct State<P> +where + P: Program + 'static, +{ + program: P, + caches: Option<Vec<user_interface::Cache>>, + queued_events: Vec<Event>, + queued_messages: Vec<P::Message>, + mouse_interaction: mouse::Interaction, +} + +impl<P> State<P> +where + P: Program + 'static, +{ + /// Creates a new [`State`] with the provided [`Program`], initializing its + /// primitive with the given logical bounds and renderer. + pub fn new( + program: P, + bounds: Size, + renderer: &mut P::Renderer, + debug: &mut Debug, + ) -> Self { + let user_interface = build_user_interface( + &program, + user_interface::Cache::default(), + renderer, + bounds, + debug, + ); + + let caches = Some(vec![user_interface.into_cache()]); + + State { + program, + caches, + queued_events: Vec::new(), + queued_messages: Vec::new(), + mouse_interaction: mouse::Interaction::Idle, + } + } + + /// Returns a reference to the [`Program`] of the [`State`]. + pub fn program(&self) -> &P { + &self.program + } + + /// Queues an event in the [`State`] for processing during an [`update`]. + /// + /// [`update`]: Self::update + pub fn queue_event(&mut self, event: Event) { + self.queued_events.push(event); + } + + /// Queues a message in the [`State`] for processing during an [`update`]. + /// + /// [`update`]: Self::update + pub fn queue_message(&mut self, message: P::Message) { + self.queued_messages.push(message); + } + + /// Returns whether the event queue of the [`State`] is empty or not. + pub fn is_queue_empty(&self) -> bool { + self.queued_events.is_empty() && self.queued_messages.is_empty() + } + + /// Returns the current [`mouse::Interaction`] of the [`State`]. + pub fn mouse_interaction(&self) -> mouse::Interaction { + self.mouse_interaction + } + + /// Processes all the queued events and messages, rebuilding and redrawing + /// the widgets of the linked [`Program`] if necessary. + /// + /// Returns a list containing the instances of [`Event`] that were not + /// captured by any widget, and the [`Command`] obtained from [`Program`] + /// after updating it, only if an update was necessary. + pub fn update( + &mut self, + bounds: Size, + cursor: mouse::Cursor, + renderer: &mut P::Renderer, + theme: &<P::Renderer as iced_core::Renderer>::Theme, + style: &renderer::Style, + clipboard: &mut dyn Clipboard, + debug: &mut Debug, + ) -> (Vec<Event>, Option<Command<P::Message>>) { + let mut user_interfaces = build_user_interfaces( + &self.program, + self.caches.take().unwrap(), + renderer, + bounds, + debug, + ); + + debug.event_processing_started(); + let mut messages = Vec::new(); + + let uncaptured_events = user_interfaces.iter_mut().fold( + vec![], + |mut uncaptured_events, ui| { + let (_, event_statuses) = ui.update( + &self.queued_events, + cursor, + renderer, + clipboard, + &mut messages, + ); + + uncaptured_events.extend( + self.queued_events + .iter() + .zip(event_statuses) + .filter_map(|(event, status)| { + matches!(status, event::Status::Ignored) + .then_some(event) + }) + .cloned(), + ); + uncaptured_events + }, + ); + + self.queued_events.clear(); + messages.append(&mut self.queued_messages); + debug.event_processing_finished(); + + let commands = if messages.is_empty() { + debug.draw_started(); + + for ui in &mut user_interfaces { + self.mouse_interaction = + ui.draw(renderer, theme, style, cursor); + } + + debug.draw_finished(); + + self.caches = Some( + user_interfaces + .drain(..) + .map(UserInterface::into_cache) + .collect(), + ); + + None + } else { + let temp_caches = user_interfaces + .drain(..) + .map(UserInterface::into_cache) + .collect(); + + drop(user_interfaces); + + let commands = Command::batch(messages.into_iter().map(|msg| { + debug.log_message(&msg); + + debug.update_started(); + let command = self.program.update(msg); + debug.update_finished(); + + command + })); + + let mut user_interfaces = build_user_interfaces( + &self.program, + temp_caches, + renderer, + bounds, + debug, + ); + + debug.draw_started(); + for ui in &mut user_interfaces { + self.mouse_interaction = + ui.draw(renderer, theme, style, cursor); + } + debug.draw_finished(); + + self.caches = Some( + user_interfaces + .drain(..) + .map(UserInterface::into_cache) + .collect(), + ); + + Some(commands) + }; + + (uncaptured_events, commands) + } + + /// Applies [`widget::Operation`]s to the [`State`] + pub fn operate( + &mut self, + renderer: &mut P::Renderer, + operations: impl Iterator<Item = Box<dyn Operation<P::Message>>>, + bounds: Size, + debug: &mut Debug, + ) { + let mut user_interfaces = build_user_interfaces( + &self.program, + self.caches.take().unwrap(), + renderer, + bounds, + debug, + ); + + for operation in operations { + let mut current_operation = Some(operation); + + while let Some(mut operation) = current_operation.take() { + for ui in &mut user_interfaces { + ui.operate(renderer, operation.as_mut()); + } + + match operation.finish() { + operation::Outcome::None => {} + operation::Outcome::Some(message) => { + self.queued_messages.push(message) + } + operation::Outcome::Chain(next) => { + current_operation = Some(next); + } + }; + } + } + + self.caches = Some( + user_interfaces + .drain(..) + .map(UserInterface::into_cache) + .collect(), + ); + } +} + +fn build_user_interfaces<'a, P: Program>( + program: &'a P, + mut caches: Vec<user_interface::Cache>, + renderer: &mut P::Renderer, + size: Size, + debug: &mut Debug, +) -> Vec<UserInterface<'a, P::Message, P::Renderer>> { + caches + .drain(..) + .map(|cache| { + build_user_interface(program, cache, renderer, size, debug) + }) + .collect() +} + +fn build_user_interface<'a, P: Program>( + program: &'a P, + cache: user_interface::Cache, + renderer: &mut P::Renderer, + size: Size, + debug: &mut Debug, +) -> UserInterface<'a, P::Message, P::Renderer> { + debug.view_started(); + let view = program.view(); + debug.view_finished(); + + debug.layout_started(); + let user_interface = UserInterface::build(view, size, cache, renderer); + debug.layout_finished(); + + user_interface +} |