Method stream

canvas/src/canvas.rs:136–159

Creates a stream for reading the instructions from this canvas

(&self)

    /// Creates a stream for reading the instructions from this canvas
    ///
    pub fn stream(&self) -> impl Stream<Item=Draw>+Send {
        // Create a new canvas stream
        let new_core    = Arc::new(Desync::new(DrawStreamCore::new()));
        let new_stream  = DrawStream::with_core(&new_core);

        // Register it and send the current set of pending commands to it
        let add_stream = Arc::clone(&new_core);
        self.core.desync(move |core| {
            // Send the data we've received since the last clear
            add_stream.sync(|stream| {
                stream.write(iter::once(Draw::ResetFrame));
                stream.write(core.main_core.get_pending_drawing())
            });

            // Store the stream in the core so future notifications get sent there
            core.streams.push(Arc::downgrade(&add_stream));

            // Wake the stream if it's not awake
            add_stream.sync(|stream| stream.take_waker().map(|waker| waker.wake()));
        });

        // Return the new stream
        new_stream
    }

    ///
    /// Retrieves the list of drawing actions in this canvas