26.09.11 13:40

Wear OS Build Configuration Summary

Originally written: January 27, 2026 Last reconciled against the tree: 2026-08-23 (S1978) Status: Ready for development

This page describes the wear module as it exists in the repository. It deliberately says nothing about Android Studio run configurations: .idea/ is gitignored, so no run configuration, default module, or startup setting travels with a clone. Choosing what to run is a local, per-developer action - see MODULE_SELECTION.md.

Build Setup

1. Annotation Processing: KSP

2. Compilation Fixes Applied

3. Build Scripts

Available in scripts/builders/:

For a release that ships the watch, the artifacts come from scripts/release/build-release-spectrum.ps1 instead, with wear in -Flavors. That script stamps one version into both app_v2 and wear first, then builds :wear:assembleStandardRelease and :wear:bundleStandardRelease (or the selected -WearFlavor) in the same invocation, so the sideload APK and the Play bundle cannot disagree about what they are (S2040). It refuses to finish if either artifact is missing.

Fast checks live on the a.ps1 launcher. The phone targets do not cover this module: fk, fkn, fr, fc and fu all check app_v2 and exit 0 without compiling a single watch file.

Neither wear builder stamps a version: both carry the constants checked into wear/build.gradle.kts. A release version is stamped into app_v2 and wear together by scripts/release/build-release-spectrum.ps1, from one timestamp, so the two modules ship one versionName and two distinct versionCodes - the watch code is the app code without its trailing minute digit, because Play refuses a release that repeats a versionCode under the shared applicationId. Gate: scripts/quality/assert-module-version-parity.ps1.

4. Documentation

Document Path Purpose
WEAR_OS_QUICK_START.md docs/WEAR_OS_QUICK_START.md Get started in 5 min
WEAR_OS_SETUP.md docs/WEAR_OS_SETUP.md Complete setup guide
MODULE_SELECTION.md docs/MODULE_SELECTION.md Pick which module you build and run

Build Status

BUILD SUCCESSFUL in 11s
40 actionable tasks: 14 executed, 26 up-to-date

APK Generated: wear/build/outputs/apk/standard/debug/wear-standard-debug.apk (S2090 added the standard/noLegal flavor dimension; pass -Flavor noLegal to the builder for the sideload variant)

Size, measured 2026-08-15 (S1679). Compare a new build against the release number - the debug one is not minified and is misleading by a factor of seven:

How to Use

In Android Studio

  1. Sync Gradle: File → Sync Now
  2. Select wear from the Run Configuration dropdown
  3. Click the green Run button
  4. Select your device/emulator

From Command Line

# Build and deploy
.\scripts\builders\build-wear-debug.PS1    # alias: .\a.ps1 wd

# Or use Gradle directly (under Build.Wear lock)
.\gradlew.bat :wear:assembleStandardDebug

Technical Details

Architecture

Module Structure

wear/
├── src/main/
│   ├── java/com/sza/fastmediasorter/wear/
│   │   ├── ui/           # Compose screens
│   │   ├── domain/       # Business logic
│   │   ├── data/         # Network & storage
│   │   └── di/           # Hilt modules
│   ├── res/
│   └── AndroidManifest.xml
└── build.gradle.kts

Key Configurations

Verification Checklist

Performance Metrics

Metric Value
Build Time ~11s (first build), ~2s (incremental)
APK Size (release) 10,808,958 bytes, measured 2026-08-15
APK Size (debug) 75,774,884 bytes - not minified, do not compare against it
Min API 28 (Wear OS 2.0)
Target API 36
Compile SDK 36

Next Steps

  1. Test Device Setup
    • Set up Wear OS emulator (Tools → Device Manager)
    • Or connect physical Wear OS device
  2. First Run
    • Select wear in the Run Configuration dropdown
    • Click Run (or Shift+F10)
    • App will build and deploy
  3. Debug/Develop
    • Use Logcat for debugging
    • Hot reload: Ctrl+M
    • Layout Inspector: Tools → Layout Inspector
  4. Release
    • Run .\scripts\builders\build-wear-release.PS1

Troubleshooting

“Module FastMediaSorter_mob_v2.wear.main not found”

File → Sync Now  # or Ctrl+Shift+Y

“KSP compilation failed”

.\gradlew.bat :wear:clean :wear:assembleStandardDebug

Wrong module selected

Check the Run Configuration dropdown in the toolbar, then check the active variant in View → Tool Windows → Build Variants. Nothing in the repository sets either one.

Emulator not appearing

.\gradlew.bat --stop  # Stop Gradle daemon

Support Resources

For quick start: See docs/WEAR_OS_QUICK_START.md For detailed guide: See docs/WEAR_OS_SETUP.md