fix(android): embedded surface renders with zero height on RN 0.85#38
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akelmanson wants to merge 1 commit into
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fix(android): embedded surface renders with zero height on RN 0.85#38akelmanson wants to merge 1 commit into
akelmanson wants to merge 1 commit into
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On RN 0.85 the embedded sandbox surface stays blank: the component runs
("Running <name>") but the native SandboxReactNativeView is laid out with
height 0. Two causes, both fixed here:
1. The native view is wrapped as position:absolute (StyleSheet.absoluteFillObject)
inside the user-styled <View>. On 0.85 an absolutely-positioned child with
all-zero insets no longer stretches to a flex-sized parent and collapses to
height 0 (width still comes from the parent's default alignItems:stretch,
masking it). Make the in-flow child flex:1 so it reliably claims the
wrapper's space.
2. onLayout positioned the nested ReactSurfaceView via layout() but never
measured it. ReactSurfaceView only pushes layout constraints to its surface
from onMeasure() (its onLayout() is a no-op until wasMeasured). Measure the
child with EXACTLY specs so updateLayoutSpecs() runs with the real size.
Verified on a device (RN 0.85.3): the embedded surface renders and lays out.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Summary
On RN 0.85 the embedded sandbox surface stays blank on Android: the bundle runs (
Running "<name>"shows in the log) but the nativeSandboxReactNativeViewis laid out with height 0 (width still fills via the parent's defaultalignItems: stretch, which masks the problem). The lib works on RN 0.80 — this is a 0.85 regression.Two independent causes, both fixed:
absoluteFillObjectcollapses to height 0. The native view is rendered asposition:absolute(StyleSheet.absoluteFillObject) inside the user-styled<View>wrapper. On RN 0.85 an absolutely-positioned child with all-zero insets (top/left/right/bottom: 0) no longer stretches to a flex-sized parent — it collapses to height 0. Making it an in-flowflex: 1child makes it reliably claim the wrapper's space.Nested
ReactSurfaceViewnever measured.onLayoutpositioned the child withlayout()but never calledmeasure().ReactSurfaceViewonly pushes layout constraints to its surface fromonMeasure()(itsonLayout()is a no-op untilwasMeasuredis true), so the nested surface kept its initial constructor constraints and rendered blank. We nowmeasure()the child withEXACTLYspecs before laying it out, soupdateLayoutSpecs()runs with the real size.Test plan
Verified on a device (RN 0.85.3 / React 19.2.3, New Architecture, Android/Waydroid x86_64): the embedded surface renders, lays out to fill its container, and receives touches. Before the change
onLayoutreportedw=742 h=0; after,w=742 h=919and the surface paints.🤖 Generated with Claude Code