SoftwareApp
7985d33869
The R8 defect fixed in the previous change was invisible to every check that existed: it passed the whole unit suite, passed lint, and worked in the debug APK, and the release APK was the only thing that disagreed. Nothing in the process had ever run it. The checklist now has a section for that, placed with the artefact work rather than at the end, because the order in which the document is meant to be worked is build, run it, then declare things to Google. It carries the install commands (the release build is a separate package, so it can sit beside the debug one and be compared directly), the MIUI trap that a bare INSTALL_FAILED_USER_RESTRICTED means its dialog was answered late rather than that the APK is bad, the paths most worth walking (thumbnails, an operation long enough to show the notification, the two SQLite databases, each viewer, the FileProvider), a dumpsys check of what the installed build actually holds rather than what the APK declares, and the one instruction that matters when something differs - assume R8 removed something instead of assuming the feature is broken, because a class named only from a resource or reached only by reflection looks unused to a shrinker. A last item points the walk at the demo library from the screenshot section, so it is repeatable and a reviewer's own files stay out of it. Renumbering meant fixing four references: two inside the checklist, and one each in STORE_LISTING (the screenshot section is now 7) and MONETISATION (pricing is now 8). A checklist that points at the wrong step is worse than one that points nowhere, so they were traced rather than assumed. Section 3 also gets a fresh measurement, since its own rule is that a stale hash is worse than no hash because it reads as though it had been checked. The record it replaces was from 2026-10-15 and predated the library views, the duplicate finder and video thumbnails: the AAB is now 5 181 628 bytes (sha256 f053d90f...) and the APK 2 294 021 bytes (sha256 afe03dea...), both versionCode 1 / versionName 1.0.0 / targetSdk 36, with the permission set unchanged and still without INTERNET or any READ_MEDIA_*. Two smaller repairs came out of the same pass. A link added in the previous commit pointed at EDGE_CASE_TESTING.md from the repository root, where it does not resolve - the changelog's other links all carry the docs/ prefix - and that was found by writing a link checker and running it over every relative link in the markdown: 37 of them, none now broken. And the re-measure warning had ended up stated twice, once per measurement record, so it now appears once, after the newest numbers and immediately before the upload steps. Documentation only; no code changed, so the suite stands at 324 JVM tests and lint clean. The walk itself was done on the phone in the previous change - what is new is that the process now asks for it, which is the part that would have caught the defect in the first place.
File Manager
An ad-free, one-time-paid Android file manager. It browses and manages the files on your device — locally, with no ads, no account and no analytics.
Nothing ever leaves the device: the app declares no network permission and contains no advertising or tracking SDKs.
Working title. The display name and the store listing are decided before the first Play upload (see docs/ROADMAP.md, M10). The
applicationIdis already fixed and can never change after the first release.
Status
M13 — video thumbnails: done. A video row shows a frame of the video itself rather than a film icon — the platform's own retriever, through Coil, with a frame taken a second in and the icon kept as the fallback when a file cannot be decoded. Before it: M12 — duplicate finder (size, then the head of every candidate, then the survivors in full), M11 — library views (a Libraries section on the root screen — Images, Videos, Audio, Documents, Archives and Recent — whose rows open ordinary listings of those files, each carrying a count from the search index), and M10 — store assets: the app is named Plain Files, the icon and feature graphic come from the app's own vectors, and docs/STORE_LISTING.md holds length-checked listing copy. Screenshots exist for 5 phone (1080×2160), 4 on a 7-inch tablet (1200×1920) and 4 on a 10-inch tablet (2560×1600) — but they predate M11, so the home screen in them is the old volume list and they will need re-shooting, which the library views make a privacy question as well as a cosmetic one (docs/STORE_LISTING.md).
Tech stack
| Area | Choice |
|---|---|
| Language | Kotlin 2.4.10 (using AGP 9 built-in Kotlin) |
| UI | Jetpack Compose, BOM 2026.06.01, Material 3 |
| Build | Gradle 9.3.1, Android Gradle Plugin 9.1.0 |
| Storage access | MANAGE_EXTERNAL_STORAGE ("All files access") with a Storage Access Framework fallback |
| Archives | Apache Commons Compress + XZ for Java (both pure Java — no NDK) |
| SDK levels | compileSdk/targetSdk 36, minSdk 26 |
targetSdk is 36 because Google Play requires new apps and updates to target
Android 16 (API 36) from 31 August 2026.
Project layout
app/src/main/java/de/softwareapp_hb/filemanager/
├── core/ Pure-Kotlin engine (no Android imports!) — paths, sorting, formatting,
│ search matching, copy/move planning, conflict policy
├── data/ Storage backends (all-files access + SAF), volumes, shares coming in
│ from other apps, the trash index (SQLite), file operations, archives,
│ deletion
├── domain/ Browser + operation controllers, models, permission state
├── service/ Foreground service for long-running file operations
├── ui/ Compose theme, browser screen, components, ViewModels
└── text/ Domain enum → string-resource mapping
app/src/test/java/… JVM unit tests for the core engine
core/ deliberately has no Android dependencies, so the trickiest logic is
covered by fast JVM tests.
Building
Prerequisites:
- JDK 17+ (JDK 25 verified)
- Android SDK with
platforms;android-36andbuild-tools;36.0.0
# Tell Gradle where the SDK lives (this file is git-ignored)
echo "sdk.dir=$HOME/Android/Sdk" > local.properties
./gradlew :app:assembleDebug # debug APK
./gradlew :app:testDebugUnitTest # JVM unit tests for the engine
./gradlew :app:lintDebug # Android Lint
./gradlew :app:bundleRelease # Play upload bundle (.aab)
Release signing is optional and driven by a git-ignored keystore.properties
(see keystore.properties.example); without it the release build still runs
R8/minification but produces an unsigned artefact.
Tracked in git
- Source, resources and Gradle build files.
docs/— roadmap and release documentation.PRIVACY.md,CHANGELOG.md, and (from M10)store-assets/.
Not tracked: local.properties, keystore.properties, *.jks, build outputs.
Releasing
Release signing is driven by the git-ignored keystore.properties (see
keystore.properties.example). Without that file the release build still runs R8 and
resource shrinking, but produces an unsigned artefact that cannot be uploaded.
./gradlew :app:bundleRelease # Play upload bundle (.aab)
./gradlew :app:assembleRelease # APK, for local checks
# Audit what is actually shipped — in particular that there is no INTERNET permission:
$ANDROID_HOME/build-tools/36.0.0/aapt2 dump permissions \
app/build/outputs/apk/release/app-release.apk
Read docs/PLAY_RELEASE_CHECKLIST.md before uploading. Step 4 is the one that matters most for this app: a file manager must declare "All files access" through Play's Permissions Declaration Form, and have the core purpose documented in its store description. PRIVACY.md is written to match the shipped permissions.
Localisation
All user-visible text lives in app/src/main/res/values/strings.xml, with real <plurals>
wherever a count can be one, and the screen and the progress notification resolve their
labels through text/TextRes.kt so the two cannot drift apart. English is currently the
only locale.
Adding a language is then a file, not a refactor:
app/src/main/res/values-de/strings.xml # same keys, translated values
Deliberately not localised, and why:
- Byte units ("KB", "MB") — symbols, not words, and every file manager and the system Settings app show them the same way.
- The timestamp pattern (
yyyy-MM-dd HH:mm) — a fixed, sortable format; the zone is passed in explicitly rather than assumed.
Checking that nothing was missed
Two things are easy to get wrong: a literal typed into a composable, and showing an enum
constant directly (FileKind.name puts untranslatable English on screen — the details
sheet used to do exactly that). The mechanical check is the pseudo-locale:
./gradlew :app:assembleDebug
# Settings > System > Languages > English (XA), then launch the debug build.
The debug build type sets isPseudoLocalesEnabled = true, so every string that came from
strings.xml renders accented and bracketed ([Îmàgé]). Anything that looks normal is a
string that never went through resources. The release build is unaffected.
One caveat: Google Play's automatic translation translates your store listing, not the app
UI. Translated UI text has to be supplied in values-<locale>/.
Known limitations
- The trash is a time window, not a bin you manage. A delete stages the item in a hidden
.plainfiles-trashfolder on the same volume and keeps it for 24 hours; the Trash entry in the overflow menu lists what is still there and puts a whole batch back. There is no "empty it now" action — expired batches are swept the next time something is deleted — and a name taken again in the meantime is never overwritten, so a restored item can arrive beside the new one rather than replacing it. - Where a trashed item came from is remembered in the app's own database, not on the volume. The staged files are the truth and the database is only an index, so the two are reconciled in both directions: an entry whose file has gone is not offered back, and a batch folder no entry mentions is swept.
- Sharing a file out only works in the all-files mode. A SAF path is relative to the
granted tree rather than a filesystem path, so it cannot be handed to
FileProvider. Receiving a share and being picked from another app's chooser work either way: the first needs no filesystem path, and the second falls back toRESULT_CANCELEDrather than returning a URI the caller could not read. - RAR, CAB, ISO and WIM are refused, not supported — they need native code, which this project deliberately does not ship. (The Commons Compress jar contains no RAR classes at all.) 7z is different: Commons Compress reads it in pure Java, so it is supported — but the format needs a seekable channel rather than a stream, because its header lives at the end of the file. All-files access can supply one; the SAF fallback cannot, so 7z extraction reports that plainly in folder mode instead of half-working.
- 7z files can be opened but not created — writing stays ZIP-only.
- Archive extraction does not restore original timestamps or permissions, and there is no archive encryption or password support.
- Cancellation happens between entries, so a single very large file finishes before a stop is honoured.
- A library is not restored across process death. The persisted view state holds a path, and a library has none, so a restart returns to the root screen rather than to Images or Recent.
- Long-press multi-select is awkward to script from the host. The gesture that opens the
selection bar (
input swipe x y x y 900) works on the MIUI test device but has also registered as a plain tap, so compress/extract from the UI wants a manual pass (see docs/EDGE_CASE_TESTING.md). - The display name is still the working title — decided before the first upload (M10).
Monetisation
One-time paid: €4.49 base, with a €2.29 launch price for the first 14 days. No ads, no subscription, no in-app purchases, no free tier.
The price lives on the Play listing, not in the build, which is why there is no Billing
client in the dependencies and no com.android.vending.BILLING permission in the APK —
that is what keeps "no network permission, nothing leaves your device" true of the
shipped artefact rather than just the source. Rationale, market anchors, the rejected
alternatives and the Console steps: docs/MONETISATION.md.
⚠️ The price must be set before the first upload — Play allows paid → free but never free → paid.
Competitive context
The category leader is File Manager Plus (AlphaInventor; 100 M+ installs, 4.7–4.8★, free with ads and in-app purchases, and a Data Safety form that shares device IDs with third parties). What it offers, what its users praise, what they complain about, and which of those complaints this app can answer without asking for a single new permission: docs/COMPETITIVE_ANALYSIS.md.
Licence
Proprietary — all rights reserved.