androidx.xr.compose.subspace.node

fun <T : Any?> CompositionLocalConsumerSubspaceModifierNode.currentValueOf(
    local: CompositionLocal<T>
): T

Returns the current value of local at the position in the composition hierarchy of this modifier's attached layout node.

Unlike CompositionLocal.current, reads via this function are not automatically tracked by Compose. Modifiers are not able to recompose in the same way that a Composable can, and therefore can't receive updates arbitrarily for a CompositionLocal.

Because CompositionLocals may change arbitrarily, it is strongly recommended to ensure that the composition local is observed instead of being read once. If you call currentValueOf inside of a modifier callback like SubspaceLayoutModifierNode.measure, then Compose will track the CompositionLocal read. This happens automatically, because these Compose UI phases take place in a snapshot observer that tracks which states are read. If the value of the CompositionLocal changes, and it was read inside of the measure or draw phase, then that phase will automatically be invalidated.

For all other reads of a CompositionLocal, this function will not notify you when the value of the local changes.

This function will fail with an IllegalStateException if you attempt to read a CompositionLocal before the node is attached or after the node is detached.

fun SubspaceLayoutModifierNode.invalidateMeasurement(): Unit

Requests a remeasure of the SubspaceLayoutModifierNode composition tree.

This is used to request a remeasure in stateful layout modifiers that are impacted by events that don't trigger a recomposition. Do not call this from SubspaceLayoutModifierNode.measure.

fun SubspaceLayoutModifierNode.invalidatePlacement(): Unit

Requests a relayout of the SubspaceLayoutModifierNode composition tree.

This is used to request a relayout in stateful layout modifiers that are impacted by events that don't trigger a recomposition. Do not call this from SubspaceLayoutModifierNode.measure.