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sync-android-egg

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Use ONLY when syncing a new Android version Easter egg from AOSP source. Covers fetching PlatLogoActivity and landroid game code from android.googlesource.com, adapting package names, adding minSdk compatibility guards, updating manifests, registering with Hilt/DI, and handling permission requests. Triggered by phrases like "sync android 18 egg", "add new android easter egg", or "基于android XX源码同步彩蛋".

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Sync Android Easter Egg from AOSP

Overview

This skill documents the end-to-end workflow for syncing a new Android platform Easter egg from AOSP source into this project. The goal is to produce a module under eggs/<VersionName>/ that matches the style of existing modules like eggs/Baklava.

Always copy or read an existing recent egg module (e.g. eggs/Baklava or eggs/VanillaIceCream) and mimic its package structure, resource naming, and Compose/Hilt wiring. Do not invent new conventions.

minSdk Compatibility (CRITICAL)

The project's minSdk is 23 (Android 6.0 Marshmallow). All AOSP upstream code targets the current platform API level and contains no compatibility guards. Every file synced from upstream MUST be checked against the API reference below.

High-risk APIs requiring SDK guards

APIMin SDKGuard pattern
NotificationChannel26if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
WindowInsets.Type.systemBars()30Use AndroidX WindowInsetsControllerCompat instead
getWindowInsetsController()30Use WindowCompat.getInsetsController()
setColorMode(COLOR_MODE_HDR)26if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
ColorSpace.get(EXTENDED_SRGB)26Lazy-init with @RequiresApi, fallback to packColor() SDR
VibratorManager31if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) + null guard
VibrationEffect.startComposition()31Same guard as VibratorManager
Handler.createAsync()28Use HandlerCompat.createAsync() from AndroidX
RELEASE_OR_CODENAME30OK if only in when else-branch (only reached on new devices)
Notification.Builder(context, channelId)26Fallback to deprecated Notification.Builder(context)
setFlag(FLAG_ONLY_ALERT_ONCE)30if (R) else setOnlyAlertOnce(true)
setRequestPromotedOngoing()BAKLAVA_1Guard with SDK_INT_FULL check

Compatibility verification checklist

After syncing each file, run these checks:

# Scan for unguarded high-API calls
grep -nE "NotificationChannel|ColorSpace|COLOR_MODE_HDR|setColorMode|VibratorManager|VibrationEffect|PRIMITIVE_SPIN|CombinedVibration|WindowInsets\.Type|setDecorFitsSystemWindows|getWindowInsetsController|Handler\.createAsync|RELEASE_OR_CODENAME" <file>

# Check imports for AndroidX compat (should use these, not raw framework)
grep -nE "WindowCompat|WindowInsetsControllerCompat|WindowInsetsCompat|HandlerCompat" <file>

If the file uses any high-API call without a Build.VERSION.SDK_INT >= guard, copy the guard pattern from eggs/Baklava or eggs/VanillaIceCream.

Critical file: UniverseProgressNotifier.kt

Do NOT simply copy from the existing egg module. The upstream version may contain new features or logic changes. Follow this process:

  1. Fetch the upstream version as part of Phase 2.1.
  2. Compare it against the most recent existing egg module's UniverseProgressNotifier.kt (e.g. eggs/Baklava):
    diff eggs/<ExistingEgg>/.../UniverseProgressNotifier.kt eggs/<NewEgg>/.../UniverseProgressNotifier.kt
    
  3. The existing version has compatibility guards (SDK checks on NotificationChannel, Notification.Builder, setFlag, setStyle, isProgressNotifierSupported, etc.) that are not in the upstream source. Preserve these guards while merging any NEW logic from upstream.
  4. If the diff shows only minor upstream changes (comments, formatting), prefer the existing module's version and adapt the package/prefix.
  5. If the upstream has significant new features, port them into the existing version's guarded structure.

Phase 0: Determine version info

  1. Identify the Android version name (e.g. CinnamonBun), API level, AOSP branch name (e.g. android17-release).

  2. Decide on a module namespace (com.android_<lowercamel>_egg), resource prefix (<lowercamel>_), and setting key (egg_mode_<lowercamel>).

  3. Confirm the branch exists on https://android.googlesource.com/platform/frameworks/base/+/refs/heads/<branch>/

  4. Scan upstream for new content: Fetch the upstream EasterEgg/AndroidManifest.xml and EasterEgg/src/com/android/egg/ directory listing. Identify any new subdirectories or declared components beyond what the previous egg module has. This prevents missing new egg content that was added in this release.


Phase 1: Fetch and adapt PlatLogoActivity.java

  1. Fetch the upstream source:

    export https_proxy=http://127.0.0.1:7890 http_proxy=http://127.0.0.1:7890 all_proxy=socks5://127.0.0.1:7890
    curl -sL "https://android.googlesource.com/platform/frameworks/base/+/refs/heads/<BRANCH>/core/java/com/android/internal/app/PlatLogoActivity.java?format=TEXT" | base64 -d > PlatLogoActivity.java
    
  2. Adapt the file:

    • Package: com.android.internal.app → com.android_<name>_egg
    • Resource: R.drawable.platlogo → R.drawable.<prefix>_platlogo
    • Starfield class: change private static class → static class (package-private for Kotlin interop)
    • shouldWriteSettings(): return true (standalone app)
  3. Add API compatibility guards — refer to the minSdk Compatibility table at the top of this skill for all required guards. Key points:

    • Window insets: use AndroidX WindowInsetsControllerCompat instead of raw WindowInsets
    • HDR color mode: wrap in Build.VERSION.SDK_INT >= Build.VERSION_CODES.O
    • VibratorManager: guard with Build.VERSION.SDK_INT >= Build.VERSION_CODES.S
    • Handler: use HandlerCompat.createAsync() instead of Handler.createAsync()
    • HDR color rendering: add @ChecksSdkIntAtLeast isSRgbExtSupported flag with packColor SDR fallback
    • ColorSpace.get: lazy-init with @RequiresApi

    After applying guards, run the grep scan from the compatibility section to verify.

  4. Remove unnecessary AOSP internals:

    • Delete measureTouchPressure / syncTouchPressure methods and related fields
    • Delete onStart() / onStop() overrides if they only call touch pressure
    • Remove import org.json.JSONObject, import static java.lang.Math.max
    • Remove ContentResolver usage if replaced by SpUtils
  5. Replace Settings.System.putLong → SpUtils.putLong(this, key, value) from com.dede.basic.SpUtils

  6. Check the upstream PlatLogoActivity for any Heptadecagram-related fixes (e.g. commit 350b4843 for the swap-to-platlogo timing fix)


Phase 2: Scan and sync EasterEgg game code

2.0 Discover ALL new content

Do NOT assume the upstream only contains landroid/. Each Android release may add, remove, or rename subdirectories. First, scan the upstream EasterEgg/src/com/android/egg/ directory to discover all content:

# List all subdirectories in the upstream EasterEgg source
curl -sL "$BASE/../?format=TEXT" | base64 -d | grep -oP '(?<=href=")[^"]+(?=")' | grep -E '^[a-z]+/
#x27;

Known historical subdirectories (for reference):

DirectoryAndroid versionContent type
landroid/S+Space exploration game
neko/NCat collector game
paint/PPaint widget
quares/QNumber puzzle
widget/SPaint chips widget

For each NEW subdirectory not present in the previous egg module:

  • Determine if it's a core feature (should be synced) or legacy relayed game (only sync if directly referenced by the new version's code).
  • Check the upstream AndroidManifest.xml for any declared activities or services in that package.

2.1 Sync landroid game code (if present)

  1. Fetch all files from EasterEgg/src/com/android/egg/landroid/:

    for f in MainActivity.kt Assets.kt Autopilot.kt Colors.kt ComposeTools.kt \
             DreamUniverse.kt Maths.kt Namer.kt PathTools.kt Physics.kt \
             Randomness.kt Universe.kt UniverseProgressNotifier.kt Vec2.kt \
             VisibleUniverse.kt; do
      curl -sL "$BASE/$f?format=TEXT" | base64 -d > "$DEST/$f"
    done
    

    Note: Assets.kt was added in Android 17. Files may vary by version.

  2. Adapt package names:

    • com.android.egg.landroid → com.android_<name>_egg.landroid
    • com.android.egg.flags → com.android_<name>_egg.flags
    • com.android.egg.R → com.android_<name>_egg.R
    • com.android.egg.ComponentActivationActivity → com.android_<name>_egg.ComponentActivationActivity
  3. Prefix ALL R.array.*, R.string.*, R.drawable.* references with <prefix>_:

    • R.array.planet_descriptors → R.array.<prefix>_planet_descriptors
    • R.drawable.ic_spacecraft_filled → R.drawable.<prefix>_ic_spacecraft_filled
  4. Replace getDessertCode() body with delegation to com.dede.basic.utils.DessertUtils.getDessertCode()

  5. Copy UniverseProgressNotifier.kt from the most recent existing egg (not upstream) to preserve compatibility guards for minSdk 23

2.2 Sync other new content (if discovered)

For any subdirectory found in step 2.0 that is not landroid/ and is not present in the previous egg module:

  1. Compare the upstream and local AndroidManifest.xml to identify new activities, services, or receivers declared in that package.

  2. Fetch all .java and .kt files from the new subdirectory, applying the same package/prefix adaptations as Phase 1 and 2.1.

  3. Fetch any new resources (res/drawable/, res/layout/, res/values/, res/xml/) that are referenced by the new code.

  4. If the new content has its own unlock/activation flow, add the necessary ComponentActivationActivity entries or ComponentProvider registrations.

  5. Check with the user whether the new content should be synced or is unnecessary legacy content carried over from the AOSP module that won't be used in this project.


Phase 3: Add support Java files

Copy from the most recent existing egg (e.g. eggs/Baklava) and adapt:

  1. flags/Flags.java — package com.android_<name>_egg.flags, always returns true
  2. ComponentActivationActivity.java — enables DreamUniverse after egg unlock

Phase 4: Resources

  1. Fetch the upstream platlogo.xml from:

    frameworks/base/+/<BRANCH>/core/res/res/drawable-nodpi/platlogo.xml
    

    Save as res/drawable-nodpi/<prefix>_platlogo.xml

  2. Copy planet/spacecraft icon drawables from the most recent existing egg, renaming the prefix:

    ic_planet_large, ic_planet_medium, ic_planet_small, ic_planet_tiny,
    ic_spacecraft, ic_spacecraft_filled, ic_spacecraft_rotated
    
  3. Create res/values/landroid_strings.xml from the most recent egg, renaming all baklava_ prefixes (or equivalent) to <prefix>_.

    IMPORTANT: Remove any duplicate string (e.g. <prefix>_egg_name) that already exists in res/values/strings.xml.

  4. Create res/values/themes.xml with <prefix>_Theme.Landroid style.

  5. Create res/xml/<prefix>_landroid_dream.xml referencing @drawable/<prefix>_platlogo.


Phase 5: AndroidManifest.xml

Following the Baklava module pattern, declare:

<uses-permission android:name="android.permission.VIBRATE"/>
<uses-permission android:name="android.permission.POST_NOTIFICATIONS"/>
<uses-permission android:name="android.permission.POST_PROMOTED_NOTIFICATIONS"/>

<activity android:name=".PlatLogoActivity" ... />
<service android:name=".landroid.DreamUniverse" android:enabled="false" ... />
<activity android:name=".landroid.MainActivity" ... />

Phase 6: Register with Hilt/DI

Create Android<VersionName>EasterEgg.kt as an @Module @InstallIn(SingletonComponent::class) object implementing both EasterEggProvider and ComponentProvider.

  • provideEasterEgg(): register with icon, name, API level, PlatLogoActivity::class.java
  • provideComponent(): provide enable/disable logic for DreamUniverse
  • provideTimelineEvents(): add release timeline entries
  • SnapshotProvider: create a preview using Starfield + plat logo

Phase 7: Permission handling (optional)

Only required if the module's AndroidManifest.xml declares runtime permissions such as POST_NOTIFICATIONS. Check the manifest first:

grep -E "uses-permission.*android:name" eggs/<VersionName>/src/main/AndroidManifest.xml

Runtime permissions (e.g. POST_NOTIFICATIONS on API 33+) need the app to request them when the relevant Activity opens. Install-time permissions (e.g. POST_PROMOTED_NOTIFICATIONS, VIBRATE) are granted automatically.

If runtime permissions are declared:

  1. Add the new module as a dependency in core/activity-actions/build.gradle.kts:

    implementation(project(":eggs:<VersionName>"))
    
  2. Add the new MainActivity class to the pagers list in core/activity-actions/src/main/java/com/dede/android_eggs/util/actions/RequestNotificationPermissionAction.kt:

    com.android_<name>_egg.landroid.MainActivity::class, // auto pilot
    

Skip this phase if no runtime permissions are declared.


Phase 8: PlatLogoActivity → MainActivity navigation

Change launchNextStage() to launch MainActivity directly instead of using the PLATLOGO category intent:

import com.android_<name>_egg.landroid.MainActivity;

// in launchNextStage:
final Intent eggActivity = new Intent(this, MainActivity.class);
startActivity(eggActivity);

Phase 9: Compile, fix, and verify compatibility

./gradlew :eggs:<VersionName>:compileDebugKotlin
./gradlew :eggs:<VersionName>:compileDebugJavaWithJavac
./gradlew :core:activity-actions:compileDebugKotlin

Common errors:

  • Duplicate resources: remove duplicates from landroid_strings.xml
  • Unresolved R.array.*: ensure all resource references have the <prefix>_ prefix
  • Unresolved com.android.egg.*: fix any remaining package references
  • API compatibility: ensure UniverseProgressNotifier has SDK guards

After compilation succeeds, re-run the compatibility checks from the minSdk Compatibility section on all synced files. The Kotlin compiler will not catch runtime API level violations — only grep-style scan or lint can detect them.

# Scan all new files for unguarded high-API calls
grep -rnE "NotificationChannel|ColorSpace|VibratorManager|VibrationEffect\.start|CombinedVibration|WindowInsets\.Type\b|setDecorFitsSystemWindows|getWindowInsetsController|Handler\.createAsync" eggs/<VersionName>/src/

Known fixes not in upstream AOSP

These fixes were applied to existing eggs and are not present in the upstream AOSP source. Apply them when syncing a new egg.

Heptadecagram swap timing fix

File: PlatLogoActivity.java
Commit: 350b4843
Issue: swapToPlatlogo() was called immediately when the 17-dot path was complete, but the user's finger is still down (tracking). This could cause the swap during a MOVE event before UP.
Fix: Set a isPendingSwapToPlatlogo flag when path completes, and only call swapToPlatlogo() on ACTION_UP:

private boolean isPendingSwapToPlatlogo = false;

// In mHeptaDecaView.setOnTouchListener:
if (heptadecagram.getPathLength() > Heptadecagram.MAX_DOTS) {
    isPendingSwapToPlatlogo = true;
    return true;
}
if (event.getAction() == MotionEvent.ACTION_UP && isPendingSwapToPlatlogo) {
    swapToPlatlogo();
    isPendingSwapToPlatlogo = false;
}

Spacecraft may enter planet interior

File: landroid/Universe.kt
Gerrit: 3743150
Issue: When landing on a planet with residual thrust, the spacecraft could penetrate the planet's interior.
Fix: Kill thrust before creating the landing:

val landing = Landing(ship, planet, a, namer.describeActivity(rng, planet))
if (ship.thrust != Vec2.Zero) {
    // kill the power
    ship.thrust = Vec2.Zero
}
ship.landing = landing

DYNAMIC_ZOOM global state not reset on destroy

File: landroid/MainActivity.kt and landroid/DreamUniverse.kt
Issue: DYNAMIC_ZOOM is a top-level var that persists across Activity/DreamService lifecycles. When autopilot is toggled ON (or screensaver starts), it is set to true, but never reset to false on destroy. Re-entering the page causes the camera zoom to still dynamically adjust based on distance.
Fix: Reset DYNAMIC_ZOOM = false in onDestroy() of both classes:

// In MainActivity.kt:
override fun onDestroy() {
    notifier?.cancel()
    DYNAMIC_ZOOM = false
    super.onDestroy()
}

// In DreamUniverse.kt:
override fun onDestroy() {
    notifier?.cancel()
    DYNAMIC_ZOOM = false
    super.onDestroy()
}

UniverseProgressNotifier live-update notification

File: landroid/UniverseProgressNotifier.kt
Commit: 85c032fd (Baklava)
Issue: Missing setRequestPromotedOngoing(true) for promoted live-update notifications; .setColorized(true) removed to avoid conflicts.
Fix: Add in the .apply {} block:

if (Build.VERSION.SDK_INT_FULL >= Build.VERSION_CODES_FULL.BAKLAVA_1) {
    setRequestPromotedOngoing(true)
}

Reference: Key files in an egg module (may vary by version)

eggs/<VersionName>/
├── build.gradle.kts                              # plugin: easter.eggs.compose.library
├── src/main/AndroidManifest.xml                  # permissions + components
├── src/main/java/com/android_<name>_egg/
│   ├── PlatLogoActivity.java                     # splash / starfield + Heptadecagram
│   ├── ComponentActivationActivity.java          # enables unlockable components
│   ├── Android<Name>EasterEgg.kt                 # Hilt registration
│   ├── flags/Flags.java                          # feature flag (always true)
│   └── landroid/                                 # space exploration game
│       ├── MainActivity.kt
│       ├── Assets.kt                             # SVG paths (new in A17+)
│       ├── Autopilot.kt / Colors.kt / ComposeTools.kt
│       ├── DreamUniverse.kt                      # screensaver
│       ├── Maths.kt / Namer.kt / PathTools.kt
│       ├── Physics.kt / Randomness.kt
│       ├── Universe.kt / Vec2.kt / VisibleUniverse.kt
│       └── UniverseProgressNotifier.kt           # notification progress
│   └── <other>/                                  # any new content discovered in Phase 2.0
└── src/main/res/
    ├── drawable-nodpi/<prefix>_platlogo.xml
    ├── drawable/<prefix>_ic_planet_*.xml         # (if landroid present)
    ├── drawable/<prefix>_ic_spacecraft*.xml      # (if landroid present)
    ├── values/landroid_strings.xml               # (if landroid present)
    ├── values/strings.xml
    ├── values/themes.xml
    └── xml/<prefix>_landroid_dream.xml           # (if DreamUniverse present)

Note: The file tree varies by Android version. For example, Assets.kt was introduced in Android 17 (CinnamonBun). Always compare with the upstream source listing and the previous egg module to determine the correct set of files to sync.


Reference: Common AOSP source locations

ComponentPath on android.googlesource.com
PlatLogoActivityplatform/frameworks/base/+/<BRANCH>/core/java/com/android/internal/app/PlatLogoActivity.java
platlogo drawableplatform/frameworks/base/+/<BRANCH>/core/res/res/drawable-nodpi/platlogo.xml
EasterEgg moduleplatform/frameworks/base/+/<BRANCH>/packages/EasterEgg/
landroid sourcesplatform/frameworks/base/+/<BRANCH>/packages/EasterEgg/src/com/android/egg/landroid/
landroid resourcesplatform/frameworks/base/+/<BRANCH>/packages/EasterEgg/res/

Use curl with proxy to fetch files in base64 format, then decode with base64 -d.