Files
simplex-chat/apps/multiplatform
fc28914455 desktop: fix saving files with '[', '*', or '?' in name on Linux (#7290)
* desktop: fix saving files with '[', '*', or '?' in name on Linux

JFileChooser's BasicFileChooserUI treats filenames containing
'[', '*', or '?' as glob patterns on Unix when the file does not
exist on disk. The Save button's ApproveSelectionAction then
applies a GlobFilter and returns without saving — the dialog
stays open and nothing is written.

Regression introduced in #2789 (commit 02d00944f, 2023-07-28),
which started pre-populating the filename via selectedFile =
File(filename). Before that the save dialog ran in
DIRECTORIES_ONLY mode and the JDK glob check never saw the
filename.

Fix: on Linux save dialogs, find the Save button by identity
(BasicFileChooserUI.getApproveSelectionAction() is public and
returns the exact ActionListener wired on the button) and
replace it with a wrapper that delegates to the original
action for non-glob names and calls approveSelection()
directly for glob names.

Windows (per the JDK only '*' and '?' are glob chars there)
and macOS (uses AWT FileDialog) are unaffected. Open dialogs
keep glob filtering for power-user search.

* desktop: always bypass JFileChooser glob-on-save on Linux

Earlier in this branch we added a heuristic to delegate to the
original ApproveSelectionAction for non-'[' names so that typing
'*.pdf' in the save dialog would still glob-filter the listing.
That preserved a Swing-only quirk that no native OS save dialog
implements:
  - macOS uses NSSavePanel (already used in this app via AWT
    FileDialog) — no glob-on-save.
  - Native Windows / Linux GTK / KDE save dialogs — no glob-on-save.
  - JFileChooser on Windows — has it, but '*' and '?' aren't even
    legal NTFS filename chars, so users won't be typing them.

It also blocks legitimate filenames containing '*' or '?' on Linux
(legal on POSIX filesystems) from being saved, since they too get
intercepted as glob.

Replace the Save button's action with a handler that always treats
the typed text as a literal filename. The result: any filename can
be saved on Linux, behaviour aligns with macOS and with every
native OS save dialog. The open dialog is untouched, so '*.pdf'
glob-filtering there still works.

* desktop: restore directory-only save dialog on Linux

The previous commit installed the literal-filename glob bypass for
every Linux save dialog (!isLoad && isLinux), including the
DIRECTORIES_ONLY mode used when filename == null — e.g. the
"Save QR code as image" flow (saveTempImageUncompressed →
saveDialog.awaitResult() with no params).

In that mode the bypass broke directory selection entirely:
selecting a subfolder + Save traversed into it instead of approving
it, and Save with an empty filename field no-oped. Net result:
QR-code image saving was unusable on Linux.

The glob-on-save bug only arises because a filename is pre-populated
(selectedFile = File(filename)), which never happens in
DIRECTORIES_ONLY mode. Gate the bypass on filename != null so the
directory-save path keeps JFileChooser's original approve action.

* desktop: simplify Linux save glob bypass via getDefaultButton

---------

Co-authored-by: shum <github.shum@liber.li>
2026-07-23 10:18:11 +01:00
..
2023-06-29 12:53:11 +01:00
2026-01-24 17:59:46 +00:00

Android App Development

This is a guide to contributing to the develop of the SimpleX android and desktop apps.

Project Overview

This is the Kotlin Multiplatform (KMP) mobile and desktop client for SimpleX Chat, sharing code between Android and Desktop (JVM) platforms using Compose Multiplatform for UI.

Build Commands

# Android debug APK
./gradlew assembleDebug

# Android release APK
./gradlew assembleRelease

# Desktop distribution (current OS)
./gradlew :desktop:packageDistributionForCurrentOS

# Run desktop/JVM tests
./gradlew desktopTest

# Run Android instrumented tests (requires connected device/emulator)
./gradlew connectedAndroidTest

# Build native libraries for all platforms
./gradlew common:cmakeBuild -PcrossCompile

# Clean build
./gradlew clean

Architecture

Module Structure

  • common/ - Shared code (Compose UI, models, business logic)
    • src/commonMain/ - Cross-platform code
    • src/androidMain/ - Android-specific implementations
    • src/desktopMain/ - Desktop-specific implementations
  • android/ - Android app container
  • desktop/ - Desktop JVM app container

Key Components (common/src/commonMain/kotlin/chat/simplex/common/)

  • model/ChatModel.kt - Main state container with reactive properties (MutableState, MutableStateFlow)
  • model/SimpleXAPI.kt - API bindings to Haskell core library via FFI
  • platform/Core.kt - FFI interface to native libapp library
  • platform/ - Platform abstraction layer (expect/actual pattern for Android/Desktop specifics)
  • views/ - Compose UI screens organized by feature (chat, chatlist, call, usersettings, etc.)
  • ui/theme/ - Design system (colors, typography, shapes)

Native Integration

The app calls into a Haskell core library via JNI/FFI:

  • CMake builds in common/src/commonMain/cpp/android/ and cpp/desktop/
  • Cross-compilation toolchains in cpp/toolchains/
  • Built libraries go to cpp/desktop/libs/ (organized by platform)

Configuration

local.properties (create from local.properties.example)

compression.level=0          # APK compression (0-9)
enable_debuggable=true       # Debug mode
application_id.suffix=.debug # Multiple app instances on same device
app.name=SimpleX Debug       # App name for debug builds

gradle.properties

Contains versions (Kotlin, Compose, AGP) and app version info. Key settings:

  • kotlin.jvm.target=11
  • database.backend=sqlite (or postgres)

Testing

Tests are in:

  • common/src/commonTest/kotlin/ - Cross-platform tests
  • common/src/desktopTest/kotlin/ - Desktop-specific tests (run with ./gradlew desktopTest)
  • android/src/androidTest/ - Android instrumented tests

Resources & Localization

  • String resources: common/src/commonMain/resources/MR/base/strings.xml + 21 language variants
  • Uses Moko Resources (dev.icerock.moko:resources) for cross-platform resource management
  • The adjustFormatting gradle task validates string resources during build

Platform-Specific Notes

Android

  • Min SDK 26, Target SDK 35
  • NDK 23.1.7779620
  • Supports ABI splits: arm64-v8a, armeabi-v7a
  • Deep linking requires SHA certificate fingerprint in assetlinks.json (see README.md)

Desktop

  • Distributions: DMG (macOS), MSI/EXE (Windows), DEB (Linux)
  • Mac signing/notarization configured via local.properties
  • Video playback uses VLCJ

Gotchas

In order for the SimpleX app to be automatically adopted for opening links from https://simplex.chat the SHA certificate fingerprint for the App installed on the phone must be in the hosted assetlinks.json file on simplex.chat.

The accepted fingerprints are in the sha256_cert_fingerprints list.

To find your SHA certificate fingerprint perform the following steps.

  1. Build and install your development version of the app as usual
  2. From the terminal in Android studio run adb shell pm get-app-links chat.simplex.app
  3. Copy the signature listed in signatures in the result
  4. Add your signature to assetlinks.json in the website repo and make a PR. On approval, wait a few minutes for the changes to propagate to the public website and then you should be able to verify SimpleX.

More information is available here. If there is no response when running the pm get-app-links command, the intents in AndroidManifest.xml are likely misspecified. A verification attempt can be triggered using adb shell pm verify-app-links --re-verify chat.simplex.app.

Note that this is not an issue for the app store build of the app as this is signed with our app store credentials and thus there is a stable signature over users. Developers do not have general access to these credentials for development and testing.

Adding icons

  1. Find a Material symbol in Rounded category.

  2. Set weight to 400, grade to -25 and size to 48px.

  3. Click on the icon, choose Android and download XML file.

  4. Update the color to black (#FF000000) and the size to "24.dp", as in other icons.

For example, this is add reaction icon.