AgentSkillsCN

layout-autolayout

为 UIKit/AppKit 布局、边距与堆叠视图，制定 Auto Layout 规范。

SKILL.md
--- frontmatter
name: layout-autolayout
description: Auto Layout rules for UIKit/AppKit layouts, margins, and stack views.
metadata:
  short-description: Auto Layout rules for UIKit/AppKit UI work.

Auto Layout

Use this skill for UI layout or visual styling work on UIKit or AppKit.

Auto Layout (Required)

All UI layout must use Auto Layout with layout anchors. Frame-based layout and autoresizing masks are not allowed for production UI.

Requirements

  • •Use Auto Layout exclusively for layout.
  • •Prefer UIStackView/NSStackView for linear layouts.
  • •Prefer layout anchors (NSLayoutAnchor APIs).
  • •Do not rely on autoresizing masks (translatesAutoresizingMaskIntoConstraints = false).
  • •Intrinsic size must be computable without overriding intrinsicContentSize. Use subview constraints, hugging/compression, and systemLayoutSizeFitting when needed.

Layout Margins (Default)

Layout margins are the default constraint reference.

UIKit:

swift
view.layoutMarginsGuide.leadingAnchor
view.layoutMarginsGuide.trailingAnchor
view.layoutMarginsGuide.topAnchor
view.layoutMarginsGuide.bottomAnchor

AppKit:

swift
view.layoutMarginsGuide.leadingAnchor
view.layoutMarginsGuide.trailingAnchor
view.layoutMarginsGuide.topAnchor
view.layoutMarginsGuide.bottomAnchor

Hard-coded Spacing

  • •Avoid hard-coded spacing constants (8, 12, 16, etc.).
  • •Prefer layout margins, intrinsic content size, and system spacing relations.
  • •Hard-coded constants are allowed only when explicitly required by design.

Valid Exceptions (Raw Anchors)

  • •Aligning sibling views
  • •Building custom controls
  • •Drawing edge-to-edge backgrounds
  • •Implementing separators
  • •Performance-critical measurement-only layout

Constraint Hygiene

  • •Keep constraints close to the views they lay out.
  • •Group and activate constraints together.
  • •Readability is required.

Platform Notes

  • •UIKit: Auto Layout + anchors + margins only.
  • •AppKit: Auto Layout + anchors + margins only; avoid springs-and-struts.

UIKit/AppKit Addendum

  • •Prefer stack views for vertical/horizontal composition; only drop to manual constraints for non-linear or performance-critical layouts.
  • •Use layoutMarginsGuide and isLayoutMarginsRelativeArrangement with stack views to respect margins by default.
  • •Use system spacing APIs before hard-coded constants.
  • •Prefer system controls over custom drawing to preserve native focus/selection behavior.
  • •Custom views should size via constraints and subview intrinsic sizes, never by overriding intrinsicContentSize.

Liquid Glass

  • •Follow the liquid-glass-design skill for Liquid Glass behavior and APIs on UIKit/AppKit.