Function Box 

pub fn Box<F>(__arg0: Modifier, __arg1: BoxSpec, __arg2: F) -> NodeId
where
    F: FnMut() + 'static,

A layout composable that stacks its children on top of each other.

Use Box to:

• Overlay elements (e.g., text over an image).
• Size a child to match its parent.
• Apply a background or border to a single child.

Arguments

• modifier - Modifiers to apply to the box layout.
• spec - Configuration for content alignment.
• content - The children composables to layout (z-order is first-to-last).

Example

Box(
    Modifier::size(100.0, 100.0).background(Color::Blue),
    BoxSpec::default().content_alignment(Alignment::Center),
    || {
        Text("Centered", Modifier::empty());
    }
);