Struct WindowRoot 

pub struct WindowRoot { /* private fields */ }

Lays its content out against the window, because nothing above it will.

A percent-sized tree resolves to nothing until something hands it a definite space, and Telar hands the tree a window rather than laying it out. Without this root the content’s rects stay zero and the window is black forever, which looks exactly like a renderer that never drew.

ScrollPage is the same shape for a window that is one scrolling column.

Implementations

impl WindowRoot

pub fn new(content: Box<dyn LayoutItem>) -> Self

Lays content’s own node out against the window, adding nothing to the tree.

content must size itself to fill the window — a percent-sized box is the usual answer. For content that sizes itself to its children instead, use WindowRoot::wrapping.

pub fn wrapping(content: Box<dyn LayoutItem>) -> Result<Self, LayoutError>

Wraps content in a window-filling box and lays that out, for content that does not fill the window on its own or that has to stretch inside a parent of a fixed size.

pub fn animate_in(self) -> Self

pub fn animate(self, transition: SurfaceTransition) -> Self

Drives the root from a transition the caller owns, so it can also send the surface back out — see SurfaceTransition::leave.

Trait Implementations

impl Component for WindowRoot

fn on_event(&mut self, event: &Event) -> EventResult

Lays out first, then passes the resize on, so anything that has to run once the tree has real rects — a scroll viewport that is its own layout root, a first-layout autofocus — sees it in that order.

Handled regardless of what the content answered: the runner requests a redraw only for a handled event (runner::handler), so reporting the content’s Ignored would relayout and never repaint.

fn view(&self) -> RenderNode

fn debug_name(&self) -> &'static str

Human-readable widget type name for the devtools tree inspector.

impl LayoutItem for WindowRoot

fn layout_node(&self) -> NodeId

fn pointer_opaque(&self) -> bool

Whether this widget stands in front of whatever its siblings drew underneath it, for a pointer event its parent is hit-testing.