# Aosp Framework Core

> AOSP Part VI — Framework Core. Use when reasoning about system_server's boot sequence (the four boot phases, service registration, Watchdog), the Intent system (Intent matching, IntentFilter, IntentResolver, package visibility, intent verification), Activity & Window Management (ActivityTaskManagerService, WindowManagerService, activity lifecycle, task/stack model, splash screens), the window system (WindowState, SurfaceControl, input dispatching, focus, IME insets, transitions), the display system (DisplayManagerService, logical vs. physical displays, HDR, brightness, refresh-rate switching), or the View system (View hierarchy, measure/layout/draw, Canvas/RenderNode, hardware acceleration). Chapters 20–25.

- Skill: `aospbooks/aosp-framework-core` (Agent Skill)
- Install (CLI): `npx skillmds@latest add aospbooks/aosp-framework-core`
- Raw SKILL.md: https://api.skillmd.com/api/skills/aospbooks/aosp-framework-core/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: AI & ML
- Author: aospbooks (https://skillmd.com/u/aospbooks)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/aospbooks/aosp-framework-core

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# AOSP Part VI — Framework Core

The Java/Kotlin layer running inside system_server that manages activities,
windows, displays, and the View tree apps render into.

## Chapters in this Part

- `20-system-server.md` — SystemServer.java, the four boot phases, service registration, Watchdog, lifecycle management, shutdown sequence
- `21-intent-system.md` — Intent matching, IntentFilter, IntentResolver, PackageManager queries, package visibility, intent verification
- `22-activity-and-window.md` — ActivityTaskManagerService, WindowManagerService, activity lifecycle state machine, task/stack model, splash screens
- `23-window-system.md` — WindowState, SurfaceControl, input dispatching, focus tracking, IME insets, transitions
- `24-display-system.md` — DisplayManagerService, logical vs. physical displays, color modes, HDR, brightness curves, refresh-rate switching
- `25-view-system.md` — View hierarchy, measure/layout/draw, Canvas/RenderNode, hardware acceleration, accessibility hooks

## When to load which chapter

- Question mentions system_server, boot phases, ServiceManager, Watchdog → `20-system-server.md`
- Question mentions Intent matching, IntentFilter, IntentResolver, package visibility → `21-intent-system.md`
- Question mentions ATM, WMS, activity lifecycle, splash screen, task/stack → `22-activity-and-window.md`
- Question mentions WindowState, SurfaceControl, input dispatch, focus, IME → `23-window-system.md`
- Question mentions DisplayManager, displays, HDR, refresh rate, brightness → `24-display-system.md`
- Question mentions View, ViewGroup, measure/layout/draw, Canvas, RenderNode → `25-view-system.md`