2503 Sections 5ac3d37c

Android Design Guidelines — Section Index

Quick reference for locating rules by category and ID.

Section Map

Rule Index

1. Material You & Theming [CRITICAL]

• R1.1 — Provide fallback static color scheme for devices below Android 12
• R1.2 — Never hardcode color hex values; use theme color roles
• R1.3 — Test with at least 3 wallpapers for dynamic color harmony
• R1.4 — Foreground elements must use matching on color role
• R1.5 — Use surface variants for backgrounds, not primary/secondary
• R1.6 — Use tertiary sparingly for accent only
• R1.7 — Always support both light and dark themes
• R1.8 — Dark theme uses tonal mapping, not pure black
• R1.9 — Provide manual theme override (System/Light/Dark)
• R1.10 — Generate tonal palettes from seed via Material Theme Builder
• R1.11 — Support dynamic color as default; custom colors as fallback

2. Navigation [CRITICAL]

• R2.1 — Navigation Bar for 3-5 destinations on compact screens
• R2.2 — Always show labels on navigation bar items
• R2.3 — Filled icons for selected, outlined for unselected
• R2.4 — Active indicator uses secondaryContainer
• R2.5 — Navigation Rail on medium (600dp+) and expanded screens
• R2.6 — Optionally include FAB in rail header
• R2.7 — Rail labels optional but recommended
• R2.8 — Modal drawer on compact, permanent drawer on expanded
• R2.9 — Group drawer items with dividers and section headers
• R2.10 — Opt in to predictive back; use OnBackInvokedCallback
• R2.11 — System back != Up button; they may navigate differently
• R2.12 — No "are you sure?" on back unless unsaved user input

3. Layout & Responsive [HIGH]

• R3.1 — Use WindowSizeClass for responsive decisions
• R3.2 — Never use fixed pixel breakpoints
• R3.3 — Support all three width size classes
• R3.4 — Max content width ~840dp on expanded screens
• R3.5 — Consistent horizontal margins per grid spec
• R3.6 — Call enableEdgeToEdge() before setContent
• R3.7 — Use WindowInsets to pad content from system bars
• R3.8 — Scrollable content scrolls behind transparent system bars
• R3.9 — Detect fold/hinge; avoid content across fold
• R3.10 — Use ListDetailPaneScaffold for foldable-aware layouts

4. Typography [HIGH]

• R4.1 — Use sp units for all text sizes
• R4.2 — Minimum 12sp body text, 11sp labels
• R4.3 — Reference MaterialTheme.typography roles, not hardcoded sizes
• R4.4 — Test at 200% font scale; no clipping
• R4.5 — Line height 1.2-1.5x font size

5. Components [HIGH]

• R5.1 — At most one FAB per screen
• R5.2 — FAB at bottom-end, above Navigation Bar
• R5.3 — FAB uses primaryContainer by default
• R5.4 — Prefer ExtendedFloatingActionButton with label
• R5.5 — Small top app bar for most screens; medium/large for prominent titles
• R5.6 — Connect scroll behavior to top app bar
• R5.7 — Limit action icons to 2-3; overflow the rest
• R5.8 — Modal bottom sheets for supplementary; standard for persistent
• R5.9 — Bottom sheets must have visible drag handle
• R5.10 — Sheet content must be scrollable if it overflows
• R5.11 — Dialogs for critical decisions only
• R5.12 — Confirm button is text button; dismiss on left
• R5.13 — Dialog titles are concise questions or statements
• R5.14 — Snackbars for brief non-critical feedback
• R5.15 — Snackbars above Navigation Bar, below FAB
• R5.16 — Include undo action when operation is reversible
• R5.17 — Correct chip type for use case (Filter/Assist/Input/Suggestion)
• R5.18 — Chips in horizontal scroll or flow layout, not stacked vertically

6. Accessibility [CRITICAL]

• R6.1 — Every interactive element needs contentDescription
• R6.2 — Describe action/meaning, not visual appearance
• R6.3 — mergeDescendants for grouped related elements
• R6.4 — Provide customActions for swipe/long-press actions
• R6.5 — Minimum 48x48dp touch targets
• R6.6 — Do not reduce touch targets to save space
• R6.7 — Text contrast >= 4.5:1 normal, >= 3:1 large
• R6.8 — Never use color alone to convey information
• R6.9 — Support bold text and high contrast settings
• R6.10 — Logical focus order (top-to-bottom, start-to-end)
• R6.11 — Move focus to logical target after navigation/dialog dismissal
• R6.12 — Full operability via TalkBack, Switch Access, keyboard

7. Gestures & Input [MEDIUM]

• R7.1 — No interactive elements in system gesture zones
• R7.2 — Use WindowInsets.systemGestures to detect conflict zones
• R7.3 — Swipe-to-dismiss must be undoable or confirmed
• R7.4 — Non-gesture alternatives for all gesture actions
• R7.5 — Material ripple on all tappable elements
• R7.6 — Long press for context menus; never the only access path
• R7.7 — Haptic feedback on long press

8. Notifications [MEDIUM]

• R8.1 — Separate channels for each notification type
• R8.2 — Choose importance levels conservatively
• R8.3 — All notifications must have a tap action
• R8.4 — Notification icons need contentDescription
• R8.5 — MessagingStyle for conversations
• R8.6 — Direct reply actions on message notifications
• R8.7 — "Mark as read" action on message notifications
• R8.8 — Use expandable styles for rich content
• R8.9 — Foreground service notifications describe operation + stop action

9. Permissions & Privacy [HIGH]

• R9.1 — Request permissions in context, not at launch
• R9.2 — Show rationale before requesting
• R9.3 — Graceful degradation on denial
• R9.4 — Never request unnecessary permissions
• R9.5 — Use Photo Picker instead of READ_MEDIA_IMAGES
• R9.6 — Prefer ACCESS_COARSE_LOCATION unless precise is essential
• R9.7 — One-time permissions for camera/mic in non-recording contexts
• R9.8 — Privacy indicator when camera/mic actively in use

10. System Integration [MEDIUM]

• R10.1 — Glance API for widgets with dynamic color
• R10.2 — Widgets must work immediately after placement
• R10.3 — Multiple widget sizes where practical
• R10.4 — Rounded corners matching system widget shape
• R10.5 — 2-4 static shortcuts; support dynamic shortcuts
• R10.6 — Shortcut icons: simple silhouettes on circular background
• R10.7 — Test shortcuts via long-press and Settings
• R10.8 — Android App Links for public content URLs
• R10.9 — Share sheet with rich previews
• R10.10 — Handle incoming share intents with content type filtering

Cross-References