marc walter

Configure CircleCI to build and sign an Android app


For the TonUINO Android app I wanted to setup a CI system that also creates github releases.

The initial configuration worked (and is triggered after I push a vX.Y.Z tag to the repository) at first, but unfortunately an Android app must be signed before it can be deployed to and executed on an actual device.

So this is how I set up signing on CircleCI in addition to compilation, test execution and creating apk releases.

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TonUINO NFC Tools Android App

2019-05-16 (Last updated on 2019-11-06)

I wrote an Android app for the FOSS TonUINO DIY music box. The box uses NFC tags to play different music files (or in my case audio books) while being usable by small children.
With it one can easily read the contents of the NFC tags that TonUINO uses and change the values as needed or copy them.

It needs an Android device with enabled NFC (and support for NXP MIFARE Classic or MIFARE Ultralight (since v0.6)) and then the necessary data may be written by pressing one button.

I released the code on Github and the app on Google Play and F-Droid.

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Updating code for Elm 0.19


This site contains a couple of examples in the Elm language. Recently, the version Elm 0.19 was released which introduced quite a few breaking changes.
But fortunately upgrading was made easy thanks to the official upgrade docs and the tool elm-upgrade.

I updated the following posts for Elm 0.19:

Note: Upgrading each post took between 15 and 90 minutes.

Elm Oauth integration (1 of 2 - GitHub)

2018-06-16 (Last updated on 2018-09-07)

Example app animation


I am working on a web service that a user may access without registration, but where she may invite other people via email.
To mitigate misuse of the service for spam, I decided to require a validated email address before the user may invite someone else. One simple way is to send a registration email to the user to activate the feature.
But I also want the possibility to add the email feature without requiring the user to wait for an email.
To achieve this, I decided to use OAuth 2.0 integration, and first use GitHub.

TLDR: Example code written in JavaScript with koa for the server and in elm for the client is available for download and on github.

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