Function Canvas 

pub fn Canvas(
    __arg0: Modifier,
    on_draw: impl Fn(&mut dyn DrawScope) + 'static,
) -> usize

A composable that draws custom content using a DrawScope.

Canvas(
    Modifier::empty().size_points(200.0, 100.0),
    |scope| {
        scope.draw_rect(Brush::solid(Color::RED));
    },
);