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Layout without extra native views

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Kuito automatically omits native objects for containers used only for layout. Their layout nodes remain, so spacing and flex behavior are preserved. Use this page to understand why a layout wrapper is absent from a native inspector.

04 / VIEW FLATTENING A container that only lays out gets no native view Its node stays in the shared layout tree; its children's views join the nearest ancestor that has one. Automatic, decided by the kernel. KUITO TREE <VStack gap={12}> <Text>Title</Text> <HStack backgroundColor="…"> <Text>Body</Text> </HStack> </VStack> VStack: layout props only → layout-only LAYOUT TREE VStack node Text node HStack node Text node Every node keeps sizing and placing its children, view or not. NATIVE VIEWS Parent view Text view · offset by the VStack HStack view · has a background Text view No view for the VStack: one less native object to create and lay out. Layout-only: VStack · HStack · Box · Spacer, layout props only, no handler, no ref, no animation. The prop's key decides, not its value.

A layout-only wrapper

tsx
import { Text, VStack } from 'kuito';

export function Summary() {
  return (
    <VStack padding={16} gap={8}>
      <Text>Order ready</Text>
      <Text>Collect at the counter</Text>
    </VStack>
  );
}

The stack can be flattened: its labels become children of the nearest native ancestor, offset by the stack's layout position. The wrapper still exists in the logical and layout trees.

What requires a view

Only plain VStack, HStack, Box and Spacer containers are candidates. Every supplied prop must be layout-only, and the node must have no handler, ref, animation or UI-thread motion binding. Paint, accessibility and interaction props require a native object.

Eligibility depends on prop keys, not their current values. A conditional backgroundColor keeps a native object even when its current value is null. This avoids creating and destroying views whenever the condition changes.

Promotion and demotion

The runtime decides flattening during commit and sends a Flatten operation when eligibility changes. The renderer reparents descendant views, preserves order and adjusts their frames. The layout node remains stable throughout.

For a renderer change, test a flattened wrapper inside a scroll host, a keyed child move, and promotion caused by adding a visual prop. Hit testing and accessibility must still reach the same logical targets. There is no public collapsable switch to maintain.