Struct ChildLayout 

pub struct ChildLayout<'a> { /* private fields */ }

What a CustomMultiChildLayout’s function is handed: its children, by key, to measure and to place.

Implementations

impl<'a> ChildLayout<'a>

pub fn has_child(&self, key: impl Hash) -> bool

Whether a child was given under key: a layout whose children come and go asks before it measures.

pub fn layout_child( &mut self, key: impl Hash, constraints: ChildConstraints, ) -> Size

Lays the child named key out under constraints and says how big it came out. A child never laid out is not shown; one laid out twice keeps the second answer.

Panics

If no child was given under key, as the reference’s does: the layout is asking about something that is not there, and a size made up for it would be placed.

pub fn position_child(&mut self, key: impl Hash, at: Point)

Puts the child named key with its top left corner at at, from the layout’s own top left. A child laid out and never placed is at the corner.

Panics

If no child was given under key.