blitz_shell/
event.rs

1use blitz_traits::navigation::NavigationOptions;
2use blitz_traits::net::NetWaker;
3use futures_util::task::ArcWake;
4use std::sync::atomic::{AtomicBool, Ordering};
5use std::sync::mpsc::{Receiver, Sender, channel};
6use std::{any::Any, sync::Arc};
7use winit::{event_loop::EventLoopProxy, window::WindowId};
8
9#[cfg(feature = "accessibility")]
10use accesskit_xplat::WindowEvent as AccessKitEvent;
11
12#[derive(Debug, Clone)]
13pub enum BlitzShellEvent {
14    Poll {
15        window_id: WindowId,
16    },
17
18    /// The renderer for this window has finished its async initialization. The
19    /// embedder should call `View::complete_resume` to transition the view into
20    /// an active state.
21    ResumeReady {
22        window_id: WindowId,
23    },
24
25    RequestRedraw {
26        doc_id: usize,
27    },
28
29    /// Close a window programmatically (e.g. a custom titlebar close button).
30    /// Handled identically to `WindowEvent::CloseRequested`.
31    CloseWindow {
32        window_id: WindowId,
33    },
34
35    /// An accessibility event from `accesskit`.
36    #[cfg(feature = "accessibility")]
37    Accessibility {
38        window_id: WindowId,
39        data: Arc<AccessKitEvent>,
40    },
41
42    /// An arbitary event from the Blitz embedder
43    Embedder(Arc<dyn Any + Send + Sync>),
44
45    /// Navigate to another URL (triggered by e.g. clicking a link)
46    Navigate(Box<NavigationOptions>),
47
48    /// Navigate to another URL (triggered by e.g. clicking a link)
49    NavigationLoad {
50        url: String,
51        contents: String,
52        retain_scroll_position: bool,
53        is_md: bool,
54    },
55
56    /// Delivered after the WASM resize-debounce window expires. Route to
57    /// `View::apply_pending_resize_if_settled`, which applies the pending
58    /// size iff motion has actually settled.
59    #[cfg(target_arch = "wasm32")]
60    ResizeSettleCheck {
61        window_id: WindowId,
62    },
63}
64impl BlitzShellEvent {
65    pub fn embedder_event<T: Any + Send + Sync>(value: T) -> Self {
66        let boxed = Arc::new(value) as Arc<dyn Any + Send + Sync>;
67        Self::Embedder(boxed)
68    }
69}
70
71#[derive(Clone)]
72pub struct BlitzShellProxy(Arc<BlitzShellProxyInner>);
73pub struct BlitzShellProxyInner {
74    winit_proxy: EventLoopProxy,
75    sender: Sender<BlitzShellEvent>,
76}
77
78impl BlitzShellProxy {
79    pub fn new(winit_proxy: EventLoopProxy) -> (Self, Receiver<BlitzShellEvent>) {
80        let (sender, receiver) = channel();
81        let proxy = Self(Arc::new(BlitzShellProxyInner {
82            winit_proxy,
83            sender,
84        }));
85        (proxy, receiver)
86    }
87
88    pub fn wake_up(&self) {
89        self.0.winit_proxy.wake_up();
90    }
91    pub fn send_event(&self, event: impl Into<BlitzShellEvent>) {
92        self.send_event_impl(event.into());
93    }
94    fn send_event_impl(&self, event: BlitzShellEvent) {
95        let _ = self.0.sender.send(event);
96        self.wake_up();
97    }
98}
99
100impl NetWaker for BlitzShellProxy {
101    fn wake(&self, client_id: usize) {
102        self.send_event_impl(BlitzShellEvent::RequestRedraw { doc_id: client_id })
103    }
104}
105
106/// Create a waker that asks the event loop to poll a window's document.
107///
108/// This lets the VirtualDom "come up for air" and process events while the main thread is blocked by the WebView.
109///
110/// All other IO lives in the Tokio runtime,
111///
112/// The request is a flag the window owns rather than a queued event, because
113/// wanting a poll is an edge and not a message: two wakes before the loop comes
114/// round mean the same thing as one. Queueing them meant an allocation and a
115/// wake syscall each, and a poll each on the far side.
116pub fn create_waker(proxy: &BlitzShellProxy, poll_requested: Arc<AtomicBool>) -> std::task::Waker {
117    struct DomHandle {
118        proxy: BlitzShellProxy,
119        poll_requested: Arc<AtomicBool>,
120    }
121    impl ArcWake for DomHandle {
122        fn wake_by_ref(arc_self: &Arc<Self>) {
123            arc_self.poll_requested.store(true, Ordering::Release);
124            arc_self.proxy.wake_up();
125        }
126    }
127
128    let proxy = proxy.clone();
129    futures_util::task::waker(Arc::new(DomHandle {
130        poll_requested,
131        proxy,
132    }))
133}
blitz_shell/event.rs

blitz_shell/
event.rs
