Another edition of the Ubuntu App Developer Week and another amazing knowledge sharing fest around everything related to application development in Ubuntu. Brought to you by a range of the best experts in the field, here's just a sample of the topics they talked about: App Developer Strategy, Bazaar, Bazaar Explorer, Launchpad, Python, Internationalization, Launchpad Translations, Unity, Unity 2D, Gedit Developer Plugins, the MyApps Portal, the App Review Board, the UbuntuSoftware Centre, Unity Mail, Launchpad Daily Builds, Ubuntu One APIs, Rapid App Development, Quickly, GooCanvas, PyGame, Unity Launcher, Vala, the App Developer Site, Indicators, Python Desktop Integration, Libgrip, Multitouch, Unity Lenses, Ubuntu One Files Integration, The Business Side of Apps, Go, Qt Quick... and more. Oh my!

And a pick of what they had to say:

We believe that to get Ubuntu from 20 million to 200 million users, we need more and better apps on Ubuntu Jonathan Lange on making Ubuntu a target for app developers

Bazaar is the world's finest revision control system Jonathan Riddell on Bazaar

So you've got your stuff, wherever you are, whichever device you're on Stuart Langridge on Ubuntu One

Oneiric's EOG and Evince will be gesture-enabled out of the box Jussi Pakkanen on multitouch in Ubuntu 11.10

I control the upper right corner of your screen ;-) Ted Gould on Indicators

• Day 1 Summary
• Day 2 Summary
• Day 3 Summary
• Day 4 Summary
• Day 5 Summary (this post)

Ubuntu App Developer Week - Day 5 Summary

Getting A Grip on Your Apps: Multitouch on GTK apps using Libgrip

In his session, Jussi talked about one of the most interesting technologies where Ubuntu is leading the way in the open source world: multitouch. Walking the audience through the Grip Tutorial, he described how to add gesture support to existing applications based on GTK+ 3. He chose to focus on the higher layer of the uTouch stack, where he explained the concepts on which libgrip, the gesture library, is built upon, such as device types and subscriptions. After having explored in detail the code examples, he then revealed that in Oneiric Eye Of GNOME and Evince, Ubuntu's default image viewer and default PDF reader, will be gesture-enabled.

Check out the session log.

Creating a Google Docs Lens

Neil introduced his session explaining the background behind Lenses: a re-architecture effort of the now superseded Places concept to make them more powerful, provide more features and make it easier to add features through a re-engineered API. Lenses create its own instance, add categories, filters and leave the searching to Scopes. The Lenses/Scopes pairs are purely requests for data, independent of the type of UI, and being provided by the libunity library, they can be written in any of the programming languages supported by GObject Introspection (Python, Javascript, C/C++, Vala, etc.). To illustrate all of this concepts, Neil devoted the rest of the session to a real example of creating a Lens for Google Docs.

Check out the session log.

Practical Ubuntu One Files Integration

Another hands-on session from Michael, with a real world example on how to supercharge apps with cloud support. Using his experience in integrating the Ubuntu One Files API to Deja Dup, the default backup application in Ubuntu, he went in detail through the code of a simple program to talk to a user's personal Ubuntu One file storage area. We liked Michael's session so much that it will very soon be featured as a tutorial on developer.ubuntu.com!

Check out the session log and Michael's awesome notes.

Publishing Your Apps in the Software Center: The Business Side

Ubuntu directly benefits from Canonical becoming a sustainable business to support its development, and that's exactly what John talked about. Being responsible for business development in the Ubuntu Software Centre, he's got a privileged  insight on how to make it happen. He started off explaining that the main goal is to present Ubuntu users with a large catalog of apps available for purchase, and then continued concentrating on how to submit paid applications to be published in the Software Centre. A simple 5-step process, the behind-the-scenes work can be summarized in: Canonical helps packaging the app, it hosts the app and provides the payment via pay.ubuntu.com, in a 80%/20% split. Other highlights include the facts that only non-DRM, non-licensed apps cannot be submitted right now, but there is ongoing work to implement license key support, and that MyApps, the online app submission portal, can take any nearly any content: apps with adverts, "free" online game clients and HTML5 apps.

Check out the session log.

Writing an App with Go

Gustavo's enthusiasm for Go, the new programming language created by Google shows every time you start a conversation with him on that topic. And it showed as well on this session, in which he created yet another "Hello world" application in a new language -you guessed-: Go. Along the way, he had time to describe all of the features of this new addition of the extensive family of programming languages: statically compiled with good reflection capabilities, structural typing, interfaces and more.

Check out the session log.

Qt Quick At A Pace

Closing the week on the last -and surprise- session, we had the luxury of having Donald, from the Nokia Qt team, the makers of Qt itself, to talk about Qt Quick. Using a clear and concise definition, Qt Quick is an umbrella term used to refer to QML and its associated tooling; QML being a declarative markup language with tight bindings to Javascript. A technology equally suited to mobile or to the desktop, QML enables developers to rapidly create animation-rich, pixmap-oriented UIs. Through the qtmediahub and Qt tutorial examples, he explored QML's capabilities and offered good practices for succesfully developing QML-based projects.

Check out the session log.

Wrapping Up

Thanks a lot for participating. I hope you enjoyed it  as much as I did, and see you again in 6 months time for another week full with app development goodness!

Ubuntu App Developer Week - Day 4 Summary

Creating an App Developer Website: developer.ubuntu.com

Creating the concept and implementing a site for app developers is no easy task. The Ubuntu App Developer site is meant to be a place for app authors to get started with development, to find the information they need and to be able to publish their apps in the Software Centre. John explained all the research and user testing that happened behind the scenes, highlighting the key findings, while David focused on the purpose of the site, where it fits in the overall developer strategy for Ubuntu and the plans for the future.

Check out the session log here.

Rapid App Development with Quickly

Fitting nicely topicwise with the questions about the default choice of tools for Ubuntu development on the previous session, Michael gave an overview of what Quickly is and how to use it. Going through the workflow of creating your first app with Quickly, he demonstrated all the key commands and explained in detail all the bits in between.

Check out the session log here.

Developing with Freeform Design Surfaces: GooCanvas and PyGame

Rick started off the session explaining what GooCanvas and PyGame were good for: providing a 2D surface on which to construct interactive GUIs for users. Beginning with GooCanvas, he showed with a very simple example how to get started playing with 2D composing surfaces, adding images, text and doing other operations such as resizing and calculating coordinates to determine clicks. Next up was PyGame, for the same purpose, but better suited for apps with lots of animation updates without user input. He then wrapped up with three samples of simple games to study.

Check out the session log here.

Making your app appear in the Indicators

Ted Gould, the man who controls the upper right corner of our screen, talked all about indicators. The idea was to illustrate how to get the information that comes from applications and handle it to the indicators. First up was the messaging menu, a menu to handle human-to-human communication, next the application indicators, which alllow long-running apps to put statuses on the panel consistently, and finally the sound indicator, taking care of all related to sound. Each one of them explained with code examples. Nice!

Check out the session log here.

Will it Blend? Python Libraries for Desktop Integration

Marcelo shared his experience acquired with Polly, a Twitter client he developed, on using Python and libraries to let apps provide better integration to the desktop. First explaining the concept of desktop integration, stressing the fact that it's not only about visuals. The rest of the session was structured around 3 main areas: how to send notifications to the user, where to place files read or written by an app and what to use to store sensitive information. A very clear and solid session, also with example code for easy learning.

Check out the session log here.

The Day Ahead: Upcoming Sessions for Day 4

16.00 UTC - Getting A Grip on Your Apps: Multitouch on GTK apps using Libgrip

Multitouch is everywhere these days, and now on your desktop as well -brought to you by developers such as Jussi Pakkanen, who'll guide through using libgrip to add  touch support to your GTK+ apps. Learn how to use this cool new library in your own software!

17:00 UTC - Creating a Google Docs Lens

Lenses are ways of presenting data coming from different sources in Unity. Neil Patel knows Lenses inside out and will present a practical example of how to create a Google Docs one. Don't miss this session on how to put two cool technologies together!

18:00 UTC - Practical Ubuntu One Files Integration

Yet again the Deja-dup rockstar and UADW regular Michael Terry will be sharing his deep knowledge on developing apps. This time it's about adding cloud support to applications: integrating with the Ubuntu One files API.

19:00 UTC - Publishing Your Apps in the Software Center: The Business Side

Closing the series of sessions around publishing apps in the Software Centre, we'll have the luxury of having John Pugh, from the team that brings you commercial apps into the Software Centre and who'll be talking about the business side of things.

20:00 UTC - Writing an App with Go

Go is the coolest kid around in the world of programming languages. Gustavo Niemeyer is very excited about it and will be showing you how to write an app using this language from Google. Be warned, his enthusiasm is contagious!

20:00 UTC - Qt Quick At A Pace

A last minute and very welcome addition to the schedule. In his session Donald Carr will introduce you to Qt Quick to create applications with Qt Creator and QML, the new declarative language that brings together designers and developers.

Looking forward to seeing you all there!