Suggestion: Add `WidgetMutRef`

General
1

I really wish there would be a WidgetMutRef trait for the following use case:

trait Screen: WidgetMutRef {}

struct Screen1 {
  list_state: ListState,
}

impl Screen for Screen1 {}

impl WidgetMutRef for Screen1 {
    fn render_ref(&mut self, area: Rect, buf: &mut Buffer) {
        StatefulWidget::render(
            List::new(["Item 1", "Item 2"]),
            area,
            buf,
            // this would fail with `WidgetRef` or with any other attempt, because `Screen1` isn't mutable borrowed...
            &mut self.list_state 
        );
    }
}

struct App {
    screens: Vec<Box<dyn Screen>>
}

impl App {
    fn draw(&mut self, frame: &mut Frame) {
        let screen: &mut Box<dyn Screen> = self.screens.last_mut().unwrap();
        frame.render_widget(screen, frame.area());
    }
}

the only solution for this which I’m using now, thanks to claude:

pub trait Screen {
    fn render(&mut self, area: Rect, buf: &mut Buffer);
}

impl<'a> Widget for &'a mut (dyn Screen + 'static) {
    fn render(self, area: ratatui::prelude::Rect, buf: &mut ratatui::prelude::Buffer)
    where
        Self: Sized,
    {
        Screen::render(self, area, buf);
    }
}

howerve, I find this really ugly.

I think, introducing a WidgetMutRef would fix this issue in a more beautiful way:

trait WigdetMutRef {
  fn render_mut_ref(&mut self, area: Rect, buf: &mut Buffer);
}
2

Ok, I just found this example:

However, this can’t be really used in my example above, since I’d somehow create the correct custom Widget, which contains (mutable) references to attributes within the State which are `Box`