Function update

examples/huge_scatter.rs:24–30

(widget: &mut PlotWidget, message: Message)

}

fn update(widget: &mut PlotWidget, message: Message) {
    match message {
        Message::PlotMessage(plot_msg) => {
            widget.update(plot_msg);
        }
    }
}

fn view(widget: &PlotWidget) -> Element<'_, Message> {
    widget.view().map(Message::PlotMessage)