This is just a quick blog post to share my excitement for the new iPhone OS firmware version 4.0, which was announced by Apple just a few days ago. Yesterday I installed the beta version of this new OS on my phone, only to find out that a few of the new features are not supported on iPhone 3G 
Unfortunately, those features will be available only on iPhone 3GS. Nonetheless, I am very excited about all this new stuff and want to go over the most interesting features, both from a user’s and a developer’s perspective.
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Author Archive
iPhone OS 4.0
April 11th, 2010 by Tom van Zummeren(http://blog.jteam.nl/2010/04/11/iphone-os-4-0/)
Free Java hosting with the Google App Engine
February 4th, 2010 by Tom van Zummeren(http://blog.jteam.nl/2010/02/04/free-java-hosting-with-the-google-app-engine/)
Lately I have been looking into and playing around with the Google App Engine. In this post I want to give a little introduction to the Google App Engine, why it can be interesting and how to work with it.
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Exploring the world of Android :: Part 3
October 8th, 2009 by Tom van Zummeren(http://blog.jteam.nl/2009/10/08/exploring-the-world-of-android-part-3/)
In my travels through the world of Android I faced a lot of challenges. Brave as I am, *cough* I conquered each one of them. A few of the challenges include saving activity state, asynchronous tasks, pagination, error handling, context/option menu’s and even drawing custom application/tab icons in Photoshop! Some challenges I already shared with you guys, but there is one challenge in particular I would like to elaborate on this time.
The app I am currently building is getting larger every day, and so is the main Activity class! Because my main activity contains a TabHost with a bunch of tabs, it also contains references to all individual view components contained in those tabs. All kinds of listeners are registered on those components so the activity contains some inner and anonymous classes as well. So you could say that this activity now has way too much responsibility! What I was looking for, is a way to separate the main activity into multiple parts, each with its own clear responsibility.
As it turns out, you can create custom components for a single piece of functionality within an Activity. Exactly what I was looking for!
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Exploring the world of Android :: Part 2
September 17th, 2009 by Tom van Zummeren(http://blog.jteam.nl/2009/09/17/exploring-the-world-of-android-part-2/)
And I’m back! Reporting live on the glorious adventures in the exciting world of Android. This blog post is the second one in the Android series. This time with code samples! Yeah!
In my first blog post about Android I talked about setting up a project using Android. This time I want to discuss a more “advanced” topic: ListView performance. A ListView is a view component which allows you to display and scroll through a list of items. It can display simple text in each row, but is also able to display a more complicated structure. In the latter case you will need to make sure your ListView still performs well (read: renders fast and scrolls smoothly). I am going to provide solutions to a few different performance problems when using a ListView
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Exploring the world of Android :: Part 1
September 8th, 2009 by Tom van Zummeren(http://blog.jteam.nl/2009/09/08/exploring-the-world-of-android-part-1/)
For a short while now, I am developing for the Android platform, which is a mobile phone operating system developed by Google. The language to use is Java, so at least I didn’t have to learn an entirely different new language and I can use the tools I already know and love. I would like to tell you about my ‘adventures’ as I explore the world of Android 
When I first started studying the Dev Guide I soon discovered that the recommended IDE for developing Android applications is Eclipse. Which was a bit disappointing because I don’t like Eclipse that much. But fortunately the kind folks of Google left room for other IDE’s to develop with. They explain that when you use another IDE you will have to use all kind of command line tools instead, which they provide. Those command line tools allow you to compile your code for Android, run your application in a phone emulator, connect a debugger to your emulator, view application logs and stuff like that. But what they didn’t mention, is that if you use Intellij IDEA (which happens to be my favorite IDE) it also provides good support for Android! This makes the use of most provided command line tools superfluous.
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iPhone as the guide to Lowlands Paradise
July 24th, 2009 by Tom van Zummeren(http://blog.jteam.nl/2009/07/24/iphone-as-the-guide-to-lowlands-paradise/)
Recently I have become interested in developing apps for the iPhone. I am about to finish my first app called “LLowGuide”, which is supposed to be a guide for a Dutch music festival called Lowlands. Lowlands will take place on the 21st, 22nd and 23rd of august 2009. As of the moment of writing, I submitted a very early version of the app into the iPhone’s App Store. But it has been in review for 8 days now, with no indication of when the review will be finished. I am starting to doubt whether I am able to release the final version before the festival starts. But in any case, it was a great iPhone programming exercise.
While developing I gathered some good practices, which could be applied in other apps as well. I want to share with you a few practices which I found particularly useful while developing the app. I hope that this way you get excited about iPhone programming (if you weren’t already) and get motivated to write your own app (if you didn’t already).
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Testing with factories
July 10th, 2009 by Tom van Zummeren(http://blog.jteam.nl/2009/07/10/testing-with-factories/)
On July 1st, Jelmer added a very useful blog post about testing the database layer in which he suggested to use “insert statement” and “fixture” classes to provide a good way to insert test data into your database. I am also using that technique as I’m writing unit tests for the database layer. I have to say this really makes unit tests less work to write, more focussed and therefore more fun to write!
Although this technique solves the challenges we have in database layer tests, we might encounter similar challenges when writing unit tests for other layers (such as the service or frontend layer). This is because such tests often also require “test data” you need to create. Only this time the test data is not in the form of database rows, but in the form of Java objects. Such objects need to be instantiated in a valid state and often depend on other objects. I find this quite similar to inserting rows into database tables having not null columns and/or foreign key constraints.
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Simple forms with Spring MVC 2.5
May 14th, 2009 by Tom van Zummeren(http://blog.jteam.nl/2009/05/14/simple-forms-with-spring-mvc-2-5/)
Having used the Spring MVC 2.5 webframework for a while now, I felt the urge to blog about some of the experiences I had with it. Especially about the part concerning forms, validation, binding and property editors. That’s the part that was usually provided to you by the SimpleFormController (in the ‘old’ Spring MVC). But now, in Spring MVC 2.5, where do you start? You don’t have a convenient base class anymore that tells you what methods you can override. Instead you have a bunch of annotations and a lot of magic.