Implement request_redraw

src/platform_impl/stdweb/event_loop.rs

@@ -32,19 +32,19 @@ impl DeviceId {
 
 pub struct EventLoop<T: 'static> {
     elw: RootELW<T>,
-    runner: EventLoopRunnerShared<T>
 }
 
 pub struct EventLoopWindowTarget<T: 'static> {
-    pub(crate) canvases: RefCell<Vec<CanvasElement>>,
-    _marker: PhantomData<T>
+    pub(crate) runner: EventLoopRunnerShared<T>,
 }
 
 impl<T> EventLoopWindowTarget<T> {
     fn new() -> Self {
         EventLoopWindowTarget {
-            canvases: RefCell::new(Vec::new()),
-            _marker: PhantomData
+            runner: Rc::new(ELRShared {
+                runner: RefCell::new(None),
+                events: RefCell::new(VecDeque::new())
+            })
         }
     }
 }
@@ -61,9 +61,9 @@ impl<T> EventLoopProxy<T> {
     }
 }
 
-type EventLoopRunnerShared<T> = Rc<ELRShared<T>>;
+pub type EventLoopRunnerShared<T> = Rc<ELRShared<T>>;
 
-struct ELRShared<T> {
+pub struct ELRShared<T> {
     runner: RefCell<Option<EventLoopRunner<T>>>,
     events: RefCell<VecDeque<Event<T>>>, // TODO: this may not be necessary?
 }
@@ -80,7 +80,6 @@ impl<T> EventLoop<T> {
                 p: EventLoopWindowTarget::new(),
                 _marker: PhantomData
             },
-            runner: Rc::new(ELRShared::blank()),
         }
     }
 
@@ -95,14 +94,11 @@ impl<T> EventLoop<T> {
     pub fn run<F>(mut self, mut event_handler: F) -> !
         where F: 'static + FnMut(Event<T>, &RootELW<T>, &mut ControlFlow)
     {
-        // TODO: Create event handlers for the JS events
         // TODO: how to handle request redraw?
         // TODO: onclose (stdweb PR)
         // TODO: file dropping, PathBuf isn't useful for web
-        let EventLoop { elw, runner } = self;
-        for canvas in elw.p.canvases.borrow().iter() {
-            register(&runner, canvas);
-        }
+        let runner = self.elw.p.runner;
+        
         let relw = RootELW {
             p: EventLoopWindowTarget::new(),
             _marker: PhantomData
@@ -156,6 +152,9 @@ impl<T> EventLoop<T> {
             });
         });
         stdweb::event_loop(); // TODO: this is only necessary for stdweb emscripten, should it be here?
+
+        // Throw an exception to break out of Rust exceution and use unreachable to tell the
+        // compiler this function won't return, giving it a return type of '!'
         js! {
             throw "Using exceptions for control flow, don't mind me";
         }
@@ -164,7 +163,7 @@ impl<T> EventLoop<T> {
 
     pub fn create_proxy(&self) -> EventLoopProxy<T> {
         EventLoopProxy {
-            runner: self.runner.clone()
+            runner: self.elw.p.runner.clone()
         }
     }
 
@@ -173,7 +172,7 @@ impl<T> EventLoop<T> {
     }
 }
 
-fn register<T: 'static>(elrs: &EventLoopRunnerShared<T>, canvas: &CanvasElement) {
+pub fn register<T: 'static>(elrs: &EventLoopRunnerShared<T>, canvas: &CanvasElement) { 
     add_event(elrs, canvas, |elrs, event: PointerOutEvent| {
         elrs.send_event(Event::WindowEvent {
             window_id: RootWI(WindowId),
@@ -229,7 +228,7 @@ fn register<T: 'static>(elrs: &EventLoopRunnerShared<T>, canvas: &CanvasElement)
 
 fn add_event<T: 'static, E, F>(elrs: &EventLoopRunnerShared<T>, target: &impl IEventTarget, mut handler: F) 
         where E: ConcreteEvent, F: FnMut(&EventLoopRunnerShared<T>, E) + 'static {
-    let elrs = elrs.clone(); // TODO: necessary?
+    let elrs = elrs.clone();
     
     target.add_event_listener(move |event: E| {
         event.prevent_default();
@@ -257,7 +256,7 @@ impl<T> ELRShared<T> {
 
     // TODO: handle event loop closures
     // TODO: handle event buffer
-    fn send_event(&self, event: Event<T>) {
+    pub fn send_event(&self, event: Event<T>) {
         match *self.runner.borrow_mut() {
             Some(ref mut runner) =>  {
                 // TODO: bracket this in control flow events?

src/platform_impl/stdweb/mod.rs

@@ -2,7 +2,7 @@ mod event_loop;
 mod events;
 mod window;
 
-pub use self::event_loop::{DeviceId, EventLoop, EventLoopWindowTarget, EventLoopProxy};
+pub use self::event_loop::{DeviceId, EventLoop, EventLoopRunnerShared, EventLoopWindowTarget, EventLoopProxy, register};
 pub use self::window::{MonitorHandle, Window, WindowId, PlatformSpecificWindowBuilderAttributes};
 pub use self::events::{button_mapping, mouse_modifiers_state, mouse_button, keyboard_modifiers_state, scancode};
 

src/platform_impl/stdweb/window.rs

@@ -1,8 +1,9 @@
 use dpi::{LogicalPosition, LogicalSize, PhysicalPosition, PhysicalSize};
+use event::{Event, WindowEvent};
 use icon::Icon;
 use monitor::{MonitorHandle as RootMH};
-use window::{CreationError, MouseCursor, WindowAttributes};
-use super::EventLoopWindowTarget;
+use window::{CreationError, MouseCursor, WindowAttributes, WindowId as RootWI};
+use super::{EventLoopWindowTarget, EventLoopRunnerShared, register};
 use std::collections::VecDeque;
 use std::collections::vec_deque::IntoIter as VecDequeIter;
 use stdweb::{
@@ -50,6 +51,7 @@ impl WindowId {
 
 pub struct Window {
     pub(crate) canvas: CanvasElement,
+    pub(crate) redraw: Box<dyn Fn()>
 }
 
 impl Window {
@@ -63,8 +65,20 @@ impl Window {
         document().body()
             .ok_or_else(|| CreationError::OsError("Failed to find body node".to_owned()))?
             .append_child(&canvas);
-        target.canvases.borrow_mut().push(canvas.clone());
-        let window = Window { canvas };
+
+        register(&target.runner, &canvas);
+
+        let runner = target.runner.clone();
+        let redraw = Box::new(move || runner.send_event(Event::WindowEvent {
+            window_id: RootWI(WindowId),
+            event: WindowEvent::RedrawRequested
+        }));
+
+        let window = Window {
+            canvas,
+            redraw
+        };
+
         if let Some(dimensions) = attr.dimensions {
             window.set_inner_size(dimensions);
         } else {
@@ -88,6 +102,7 @@ impl Window {
         window.set_decorations(attr.decorations);
         window.set_always_on_top(attr.always_on_top);
         window.set_window_icon(attr.window_icon);
+
         Ok(window)
     }
 
@@ -104,7 +119,7 @@ impl Window {
     }
 
     pub fn request_redraw(&self) {
-        // TODO: what does this mean? If it's a 'present'-style call then it's not necessary
+        (self.redraw)();
     }
 
     pub fn get_position(&self) -> Option<LogicalPosition> {