Sketch Auto Layout: Unexpected Child Layer Shift After Parent Symbol Update

Question

Symptom
When a parent symbol containing Auto Layout is updated, a child layer that has a Fixed constraint moves to a new position on the canvas. The change occurs even though the child’s constraints appear correct in the Layer Inspector.
Log Context
Sketch emits a generic warning in the Console whenever a symbol update triggers a layout recalculation. The message does not identify the specific constraint conflict or the override responsible for the shift.
Potential Interference
Batch updates that use the Distribute alignment options can override explicit Auto Layout constraints, causing inconsistent positions across instances. Additionally, symbol overrides applied via the Inspector are not logged with unique identifiers, making it difficult to trace the source of the movement.
Unresolved Questions

What causes child layers to reposition when a parent symbol’s content size changes, even with ‘Fixed’ constraints?
How can we trace which override triggered the shift given the generic console warnings?
Does the ‘Distribute’ alignment option override Auto Layout constraints during batch updates, and if so, how can this be detected?

Tasadduq Burney · Answer

Answer to the Symptom
When a parent symbol with Auto Layout is updated, Sketch recalculates the symbol’s content bounds. A child layer with a Fixed constraint is positioned relative to the parent’s current frame. If the parent grows or shrinks, the child’s anchor is re-evaluated against the new bounds and the layer appears to move on canvas even though the Layer Inspector shows Fixed.
Confirmed Facts

Sketch treats Fixed constraints as absolute positions tied to the parent’s current frame, not the original frame.
The console warning on layout recalculation is generic and does not identify the specific constraint conflict or override responsible.
Distribute alignment batch operations perform a re-layout that temporarily overrides individual Auto Layout constraints, and those overrides can persist after the batch completes.

Likely Explanation
Parent size change triggers an Auto Layout recalc. The Fixed constraint is reapplied against the new parent bounds, shifting X/Y. If a Distribute alignment was used in a batch update, it may have overwritten the child’s original constraint, compounding the shift.
Steps for This Case

Open the parent symbol and select the child layer. Record the Fixed X and Y values shown in the Layer Inspector before the update.
Remove or undo any Distribute alignment or batch update actions applied to the parent symbol, then reapply the parent update and compare the recorded X/Y.
Trigger the parent symbol update with Show Layer Hierarchy enabled and note which layer moves when the generic console warning appears.
If the child still moves after Distribute is removed, the shift is due to parent bounds change with Fixed being relative to current bounds. Consider Center or Stretch constraints for elements that must stay positioned relative to the parent.

Missing Diagnostic Detail
Provide the exact Sketch version in use. Handling of Fixed constraints and Distribute overrides changed between releases, which changes the recommended verification steps.

Sketch Auto Layout: Unexpected Child Layer Shift After Parent Symbol Update

Symptom

Log Context

Potential Interference

Unresolved Questions

1 answer

Answer to the Symptom

Confirmed Facts

Likely Explanation

Steps for This Case

Missing Diagnostic Detail

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