QRLite

An android app to make collages from pictures - No internet connection required, no ads, no machine learning, no tracking, no bloatware.

This app is built in with C++ using the Qt framework.

Features

Development environment

This project ships a devcontainer configuration (.devcontainer/devcontainer.json). The container is based on the bernedom/qtandroidbuilder image, which comes pre-installed with Qt 6, the Android NDK & SDK, Conan 2, CMake, and Ninja.

Opening the project in VS Code with the Dev Containers extension is the recommended way to get a fully working build environment without any manual setup.

Build Requirements

• conan2 as dependency manager
• cmake 3.24 or newer
• ninja (if using the ninja generator)
• Android NDK & SDK (if building for android)

Note – git submodules: This project uses cmake-conan as a git submodule. When cloning, make sure to initialise it:

git clone --recurse-submodules <repo-url>

Or, if you have already cloned without submodules:

git submodule update --init --recursive

Conan Profiles supported in the devcontainer:

Desktop (Linux):

[settings]
arch=x86_64
build_type=Release
compiler=gcc
compiler.cppstd=gnu17
compiler.libcxx=libstdc++11
compiler.version=13
os=Linux

Android

[settings]
arch=x86_64
build_type=Release
compiler=clang
compiler.cppstd=gnu17
compiler.libcxx=libstdc++11
compiler.version=18
os=Linux

Dependencies

• Qt 6
• Android NDK & SDK
• zxing-cpp
• Catch2 (for unit tests)

This project uses conan as a dependency provider for CMake. Please refer to the conan documentation for installation instructions.

Build instructions

Use cmake --list-presets to see all available build presets.

Desktop (Linux):

cmake --preset ci-ninja-desktop-debug
cmake --build build

Android (single ABI, e.g. arm64-v8a):

cmake --preset ci-ninja-android-arm64-v8a-debug
cmake --build build_android_arm64-v8a

To build the Android APK explicitly, pass the apk target:

cmake --build build_android_arm64-v8a --target apk

Available Android ABI presets: armeabi-v7a, arm64-v8a, x86_64. Replace debug with release for release builds.

Running the android emulator

Currently the emulator does not run inside the devcontainer because of missing KVM support. You can run the emulator on the host machine and connect to it from the devcontainer. To do so, you need to install the Android SDK and NDK on your host machine.

Install the system images for the android emulator using the sdkmanager then create an AVD using the avdmanager:

sudo /opt/android/cmdline-tools/cmdline-tools/bin/sdkmanager --install "system-images;android-33;google_apis;x86_64"
/opt/android/cmdline-tools/cmdline-tools/bin/avdmanager create avd -n test -k "system-images;android-33;google_apis;x86_64"

Check https://github.com/amrsa1/Android-Emulator-images for more details.

Then start the emulator:

/opt/android/emulator/emulator -avd test

Uploading the APK to the emulator can be done using adb:

/opt/android/platform-tools/adb install -r ./build_android_x86_64/QRLiteApp/android-build/QRLite.apk

Uploading and deploying to android play store

To upload the app to the play store, you need to generate a signed bundle or apk.

1. First generate a keystore if you do not have one already: keytool -genkeypair -alias upload -keyalg RSA -keysize 2048 -validity 9125 -keystore upload-key.jks
2. Export the public certificate from the keystore: keytool -export -rfc -alias upload -file upload_certificate.pem -keystore upload-key.jks
3. sign the aab jarsigner -keystore ./upload-key.jks ./build_android_bundle/QRLiteApp/android-build/build/outputs/bundle/release/android-build-release.aab upload
4. Verify the signature: `jarsigner -verify -verbose -certs ./build_android_bundle/QRLiteApp/android-build/build/outputs/bundle/release/android-build-release.aab

For CI/CD store the upload kez as base64 encoded secret and decode it during the workflow run:

base64 -w0 upload-key.jks > upload-key.jks.b64 

Sign the apk

To sign the apk for release, use the following command:

apksigner sign --ks  upload-key.jks ./build_android_armeabi-v7a/QRLiteApp/android-build/QRLite.apk

Backlog

• If permissions for camera are not (yet) granted, do not initialized camera

• Fix Icon to be round

• Functionality to read QR codes from images

  • Select from gallery
  • select from file system

• Write QR codes (later)

Tech enhancements

• Add benchmark for QR code reading
• Pull prebuilt artifacts from CI for multi-aab

Extended features for later releases

• Sanity checks for urls etc
• Auto detect types like WLAN access, vCard, mailto, ...
• Open proper app for detected types
• allow to select camera
• turn on/off flashlight

build multi arch android aab

1. configure all individual archs in debug mode:
   1. cmake --preset ci-ninja-android-armeabi-v7a-debug
   2. cmake --preset ci-ninja-android-arm64-v8a-debug
   3. cmake --preset ci-ninja-android-x86_64-debug
2. build all individual archs in debug mode:
   1. cmake --build ./build_android_armeabi-v7a
   2. cmake --build ./build_android_arm64-v8a
   3. cmake --build ./build_android_x86_64
3. collect all archs bundle in debug mode using qt-cmake /opt/Qt/6.11.1/android_x86_64/bin/qt-cmake --preset ci-ninja-android-all-archs-debug
4. build using cmake