Porting the NFC / NDEF Library to .NET Standard

NdefDemo App of the NFC Library, now based on .NET Standard

With around 20,000 downloads, the “NFC / NDEF Library for Proximity APIs” is the most popular NFC library for C#. The library has initially been released in 2012 and has since been extended to cover many standardized as well as common NDEF use cases – also thanks to the support of the netidee open innovation platform.

Lately, the underlying platforms have evolved, and now the library has adapted. The main NFC library has now been ported to .NET Standard, which is a common baseline that makes the library compatible to even more different platforms. The new version 4.1.0 is now available under the open source LGPL license on GitHub, as well as on NuGet.

In addition to running on Windows, the library now fully supports all platforms that support .NET Core (like Linux and Mac), as well as Xamarin for Android and iOS. This makes it significantly easier to provide NFC functionality across different platforms – especially now that the iPhone also finally supports the open NDEF standard within NFC through the Apple Core NFC framework. Continue reading “Porting the NFC / NDEF Library to .NET Standard”

.NET Standard Libraries and NuGet Package Wizard

Generating NuGet Packages from Visual Studio 2017

A few days ago, Microsoft has released  .NET Standard 2.0, which is the new dreams-come-true platform for libraries. Additionally, Portable Class Libraries (PCL) have since also been deprecated. Therefore, it’s about time to port my existing libraries.

In addition, also Visual Studio 2017 Version 15.3 with full support for .NET Standard 2.0 was released, as well as the latest Windows 10 Fall Creators Update Preview SDK. So, let’s get started!

.NET Standard vs. UWP

However, it turns out that UWP doesn’t yet support .NET Standard 2.0. For the UWP platform, the latest supported .NET Standard version is still 1.4, which is considerably less powerful.

Attempting to reference a .NET Standard 2.0 library from an UWP app leads to errors, including the following that gives it away:

Upgrading the UWP project to the latest SDK Preview for the Windows 10 Fall Creators Update Build 16257 doesn’t change anything; both the SDK and the new Visual Studio 2017 version 15.3 can not yet use .NET Standard 2.0 in conjunction with UWP. According to Microsoft, that will be coming soon with the next UWP version. Continue reading “.NET Standard Libraries and NuGet Package Wizard”

Resoving Unity Scene Merge Conflicts with UnityYAMLMerge (Smart Merge) and TortoiseGit

When working on Unity HoloLens-projects in teams, sometimes merge conflicts in Unity scenes are unavoidable. Even though the Unity scene file format is text-based, the automatic merge of a standard GIT merge tool wouldn’t always correctly recognize the changes from different versions.

Luckily, Unity comes with a merging tool that is specialized on scene files: UnityYAMLMerge / Smart Merge. However, it’s not straight-forward to integrate into a workflow. Continue reading “Resoving Unity Scene Merge Conflicts with UnityYAMLMerge (Smart Merge) and TortoiseGit”

Improving User Experience for Public Transport Departure Monitor

Raspberry Pi Public Transport Departure Monitor - Yellow: Medium departure time (better hurry!)

The public transport departure monitor has been incredibly helpful – it dramatically cut down the waiting times at the bus stop, as it allows to leave the apartment exactly on time to reach the bus.

The setup is based on a Raspberry Pi with a simple LCD display. I’ve combined this with a motion detecting power plug, so that the Raspberry is only active when I’m actually in the entrance area of the apartment. As such, the energy consumption is minimal. Continue reading “Improving User Experience for Public Transport Departure Monitor”

Using Netgear Arlo Security-Cameras for Periodic Recording

Automating Arlo Camera Recording

The Arlo security camera by Netgear is one of the few cameras that doesn’t need a power supply, so is easier to use outdoors. The cameras have motion-sensing integrated and upload a short video sequence around the motion event to the Netgear backend. Great about the Arlo ecosystem is that this is possible with the free plan as well; you can access the recordings of the last 7 days already with the free basic plan.

For my use case, I wanted to also take periodic pictures / recordings. These can then later be stitched together for a time-lapse. Continue reading “Using Netgear Arlo Security-Cameras for Periodic Recording”

How to Read the Battery Level of Bluetooth LE Devices

Microsoft Surface Dial

At the Microsoft Build Tour in Vienna, I had the opportunity to present an enhanced version of the Bluetooth Beacon talk. With the Windows 10 Creators Update, Microsoft released a massive update to the Bluetooth LE capabilities of the OS. This finally allows developers to use the full potential of modern Bluetooth scenarios, including sensors, wearables and beacons.

At Build 2017, Microsoft released three new sessions explaining the capabilities of the new APIs:

  1. Intro to Bluetooth LE Explorer
  2. Unpaired Bluetooth LE Device Connectivity
  3. Bluetooth GATT Server

Even though the sessions reference example code and blog posts that should have been released together with the session recordings, still none of that is available so far. That gave me the opportunity to explore the new APIs based on the short documentation overview page and the videos. Continue reading “How to Read the Battery Level of Bluetooth LE Devices”

More Realistic HoloLens Spectator View Photos

HoloLens Spectator View - Photoshop - Screen - Darkened

When capturing a Mixed Reality scene through HoloLens Spectator View, the resulting photos and videos look amazing. But how to make them more realistic? The right blending mode in Photoshop helps.

Are Spectator View Photos Real?

Of course, the captured Spectator View photo is in many ways different to what you see in HoloLens. First off, it’s only 2D; in the HoloLens, you’d see a real 3D hologram. In this area, the live HoloLens view is much more impressive.

On the other hand, the actual resolution and field of view of the HoloLens is less than a (potentially) 20 Megapixel+ Unity rendering that shows holograms all around you. But the field of view is difficult and somehow unnecessary to simulate as we’re looking on the scene from a 3rd person perspective. Continue reading “More Realistic HoloLens Spectator View Photos”

Event: Mobile Developer After-Work #15: Next Generation Apps

Mobile Developer After-Work #14

Mobile Apps are no longer simple tools and games. They have grown to amazingly complex systems. Which ingredients are necessary to successfully develop a next generation app?

You will need Artificial Intelligence / Machine Learning. Only the best performance will satisfy your customers – or do you want to wait more than a few seconds in a mobile app? How can you visualize your user interface with HoloLens?

At the #mdaw15, you will learn how to develop and plan such apps with modern frameworks. Join the next After-Work event in St. Pölten for free at https://mobility.builders/

What is a Mobile Developer After-Work Event?

#mdaw events are mixtures of conferences with more casual meet-ups. Different expert speakers approach an overall topic from diverse perspectives. Afterwards, there’s plenty of time for networking and discussion amongst attendees – with snacks and drinks, of course.

The events target mobile developers and decision makers. The goal is to dive deeper into relevant and already known topic areas, as well as to keep up to date with the constantly evolving and changing toolset of the mobile world.

In the meantime, we can look back to 14 previous #mdaw events. Topics so far included business apps, digital healthcare, Xamarin, user experience or a Refugee Hackathon. We’re organizing the events with technology partners like Microsoft, Oracle, IBM, the City of Vienna and many others.

The community has grown to around 500 attendees, and we continue to get more and more developers on board with each event!

Together with Helmut Krämer, I’ve founded the community in 2013 and am proud that it’s still around. We’ve had a tremendous impact on the Austrian developer community so far. With the upcoming #mdaw15, we’re extending the reach geographically and host our first event outside of Vienna, to reach even more developers!

How to set up HoloLens Spectator View, Bonus – Troubleshooting

HoloLens Delete Space

Did you follow the blog post series on setting up Spectator View for HoloLens? The following issues frequently occured when testing Spectator View. To make your life easier, make sure you check these troubleshooting tips & tricks:

HoloLens Sharing Offset

Between your two HoloLenses, there can be some offset in the placing of the holograms. In one HoloLens, you can for example position your hologram directly on the table; on the second HoloLens, it’s one meter next to the table. Continue reading “How to set up HoloLens Spectator View, Bonus – Troubleshooting”