Android System Function Library

A Kotlin library that wraps commonly used hidden system APIs for Android system applications. It provides a unified, version-aware interface for operations that require platform signature or system privileges.

Requires: platform signature (platform.jks) + android.uid.system shared user ID

Feature Modules

Module	Description
Launcher	Get/set default launcher, list all launchers
Status Bar / Navigation Bar	Disable expand, icons, clock, navigation buttons; switch gesture/3-button mode
Device Info	SN, IMEI, MAC, RAM, battery capacity, IP address, root detection
Time / Timezone	NTP sync, set system time/timezone, change system language
Power Management	Shutdown, reboot, factory reset, screen on/off, sleep/wake
DPM (Device Policy)	Activate admin, set Profile/Device Owner, lock screen, password policy, camera/screenshot disable, kiosk mode
App Management	Silent install/uninstall (APK & XAPK), hide, freeze/suspend, block uninstall, grant permissions, battery optimization
Storage	Mount/unmount volumes, list USB storage, clear app data
Network	WiFi config, hotspot control, Ethernet enable/disable, HTTP/global proxy, NFC enable/disable
Input Injection	Inject touch, scroll, and key events via IInputManager
Sensor Privacy	Toggle microphone/camera kill switch (Android 12–13)
System Settings	Read/write Settings.Global/System/Secure
Accessibility	Enable/disable accessibility services
OTA Update	A/B partition OTA via UpdateEngine with progress callback
Bug Report	Trigger system bug report via IActivityManager or BugreportManager
USB Management	Grant USB device permission silently, bind default handler app
Dream (Screensaver)	Get/set screensaver component, start screensaver
Device Type Detection	Detect TV, Wear OS, Android Auto
Image Utilities	Convert between Drawable, Bitmap, and ByteArray
AppOps / Permissions	Set/check AppOpsManager modes, grant runtime permissions, manage battery optimization
OEMConfig	Parse OEMConfig restriction XML entries

Android Version Compatibility

Feature	API 31 (12)	API 32 (12L)	API 33 (13)	API 34 (14)	API 35 (15)	API 36 (16)
Sensor Privacy (mic/camera toggle)	Yes	Yes	Yes	-	-	-
Ethernet enable/disable	Yes (Trackstop/Trackstart)	Yes	Yes (setEthernetEnabled)	Yes	Yes	Yes
Lock screen (screen-off only, no lock)	-	-	-	Yes	Yes	Yes
setProfileOwner (4-param)	-	-	-	Yes	Yes	Yes
setActiveAdmin (4-param)	-	-	-	-	-	Yes
setPackagesSuspendedAsUser (9-param)	-	-	-	-	Yes	Yes
NFC via INfcAdapter	Yes	Yes	Yes	Yes	-	-
NFC via NfcAdapter reflection	-	-	-	-	Yes	Yes
Wireless debugging (IAdbManager)	Yes	Yes	Yes	Yes	Yes	Yes
lockNow (2-param)	Yes	Yes	Yes	-	-	-
lockNow (3-param, with callerPackage)	-	-	-	Yes	Yes	Yes

Repository Structure

SystemFunction/
├── SystemFunction_src/     # Full source code of the library and all version-specific modules
│   ├── SystemLib/          # Core library (main entry point, unified API surface)
│   ├── Android12/          # API 31–32 compatibility implementations
│   ├── Android13/          # API 33 compatibility implementations
│   ├── Android14/          # API 34 compatibility implementations
│   ├── Android15/          # API 35 compatibility implementations
│   └── Android16/          # API 36 compatibility implementations
├── SystemLib_repository/   # Pre-built Maven repository (AAR artifacts, ready to consume)
├── API_REFERENCE.md        # Full API reference (Chinese)
└── API_REFERENCE_EN.md     # Full API reference (English)

SystemLib_repository — Pre-built Maven Artifacts

The SystemLib_repository directory is a local Maven repository. It contains pre-compiled AAR artifacts for all modules so you can consume the library without building from source.

Available artifacts (all versioned 1.0-<date>):

Artifact	Group ID	Description
systemlib	com.android.systemlib	Core library — main dependency for most projects
android12	com.android.android12	API 31–32 compatibility layer
android13	com.android.android13	API 33 compatibility layer
android14	com.android.android14	API 34 compatibility layer
android15	com.android.android15	API 35 compatibility layer
android16	com.android.android16	API 36 compatibility layer
hideapi	com.android.hideapi	Hidden API stub jar
mdmsdk	com.android.mdmsdk	MDM SDK

Typical usage: add systemlib only. It already bundles all version-specific modules internally.

SystemFunction_src — Source Code

The source project is a standard Android multi-module Gradle project. To build and publish locally:

cd SystemFunction_src
./gradlew :SystemLib:publishReleasePublicationToMavenRepository

This publishes the updated AARs back into SystemLib_repository.

Quick Start

Prerequisites

• Platform signature keystore (platform.jks) from the device manufacturer
• Your app must be signed with the platform key
• Your app must declare android.uid.system as shared user ID

1. Add repository to settings.gradle

dependencyResolutionManagement {
    repositories {
        maven { url 'https://github.com/h4de5ing/SystemFunction/raw/master/SystemLib_repository' }
        // Mirror for users in China
        maven { url 'https://gitee.com/lex1992/system-function/raw/master/SystemLib_repository' }
    }
}

2. Add dependency to build.gradle

dependencies {
    implementation 'com.android.systemlib:systemlib:1.0-20221223'
}

3. Configure signing in build.gradle

android {
    signingConfigs {
        release {
            storeFile file("platform.jks")
            storePassword 'android'
            keyAlias 'android'
            keyPassword 'android'
        }
    }
    buildTypes {
        release {
            signingConfig signingConfigs.release
        }
    }
}

4. Set shared user ID in AndroidManifest.xml

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    android:sharedUserId="android.uid.system">
    ...
</manifest>

5. Add ProGuard rule

-keep class com.android.systemlib.** { *; }

Developer Notes

System signature: You must obtain platform.jks from your device manufacturer. The APK must be signed with the platform key and installed on the system partition (or pushed via adb install on eng/userdebug builds).

API stability: Most APIs in this library use @UnsupportedAppUsage-annotated or AIDL hidden interfaces. They may change between Android versions. Always test after upgrading the target Android version.

Version-specific modules: Android12.kt through Android16.kt contain implementations that differ per API level. The unified entry point in Syslib.kt / SystemLib.kt dispatches to the correct implementation automatically.

Known limitation: copyDir() in X.kt currently only traverses the directory tree and prints paths — it does not actually copy files. Do not rely on it for file copy operations.

Issue Reporting

When filing an issue, include:

• Android version and API level (e.g. Android 14 / API 34)
• Device model and ROM variant (if relevant)
• Complete logcat output
• Minimal reproducible code

Contributing

1. Fork the repository
2. Create a feature branch
3. Commit your changes with a descriptive message
4. Push and open a Pull Request

License

Apache License 2.0