Wednesday, September 30, 2015

Another web component - upper88-title

In the weekend I published my second web component - upper88-title. Like my first one this is a vanilla JS web component, that does not use Polymer or any other library, apart from the web components polyfill. It might also be the smallest web component ever in terms of lines of code...

What it does is very simple: it allows you to tag some html in your web page as title, and the web component will grab the text (skip html tags) and set it as document title. So you don't have to type the same text over again - and can avoid the risk of forgetting to update the document title, it will always show the same text as that displayed in the actual page.

A little more advanced is that you can use Polymer data binding (even if the component itslef does not depend on Polymer) to set the content of both the HTML tag and document title at the same time. 

Tried to publish it on but it seems like the job that updates the site is broken, so you can't see it there yet.

Tuesday, September 15, 2015

Polymer summit 2015

During the day I've followed Polymer Summit 2015 over the net. Lots of good talks and useful information. I do belive that the approach of Custoim HTML elements is the future, but even though Polymer is on it's way, I don'ät think tehey are really there yet.


  • the approach of components that can be reused, extended and combined into new components
  • some really awesome components are available out there, both from Google and others
Not cons, but stuff they have to work on:
  • dependencies,build system etc: when you start a polymer project, bower will download that feels like half the internet for you, not really manageable, and my previous experiences from build system have not been to good. You really need a good build system, and preferanbvle a CDN so you don'ät have to manage all this
  • the kiving of HTML, CSS and javascript in one file seems like a step backward.
But yes,. I do think web components is the future, I only wonder when we will be there....

Web Components: no size in attachedCallback

When I made the upper88-wordclod web component everything worked fine when I had hard-coded sizes in the beginning. The library worked well and gave the ouput I expected (well, actually a bit better, it's an awesome library).

But when I switched to a size set with CSS it stopped working. After some debugging I realized that the element had no size yet. When attachedCallback(which is the place where you would render your element for the first time) is called, the element has no size set yet, so if your code (or a library you might use) relies on getting the height or width of the element ity won't work.

The recommended way is to remove all sizing from javascript and do it in CSS instead, which will work, but in my case that was not an option. Instead I had to add a call to setTimeout to make the actual rendering take place a bit later, after sizes have been calculated. That seems to work well, you don't actually see the delay and I have had no problem with the solution.

Monday, September 14, 2015

First web component published - upper88-wordcloud

Yesterday I published my first web component, It is a custom component called upper88-wordcloud. Very basic so far, you set the data using the attribute rows and optionally minimum and maximum font size using an options attribute.

An example:
Goldmedals from Track and Field World Championship 2015
Html for this:
<upper88-wordcloud options='{"maxFont":60}' rows='[["Kenya", 7], ["Jamaica", 7], ["United States", 6], ["Great Britain", 4], ["Ethiopia", 3], ["Poland", 3], ["Canada", 2], ["Germany", 2], ["Russia", 2], ["Cuba", 2]]'>

Size, background color etc are set using CSS.

For rendering the actual word cloud the component uses a library available on GitHub, wordcloud2.js by Tim Dream. A great library, and it supports rendering the wordcloud as a set of HTML span's, which feels like the best way to go for a custom element.

So far the component is very basic and doesn't expose much of the flexibility that the library has. There is definitely room for improvement.

Thursday, June 18, 2015

Polymer 1.0 First impressions

Recently at Google I/O Google announced Polymer 1.0 to be available and ready for production. Since I think that Web Components might very likely be the future for the web and since I tried Polymer 0.5 in some prototypes I thought I would give it a go and try Polymer starter kit.

If you do this make sure your Internet connection is fast: downloading the starter kitr is fast, but then downloading all dependencies takes ages, so this is no quick start.

Once you actually get started it's easy enough to start building. IUt took me just a few hours to build a small site with a few pages, working navigation etc. And it looked pretty OK:

Some reflections:

  • I do like materialized design, clean, simply and looks modern. You get that more or less for free
  • Materialized design are also good for us that are not graphic designers: you get usefulk set of icons to use, and it uses texts a lot, which is good
  • the polymer elements are easy to work with
So creating a site locally was pretty easy. Deploying is another thing, more on that later, when I actually managed to publish my new site.

Sunday, May 11, 2014

In Android May is month number four

So I published my Android app yesterday. But it didn't work as expected. Information was missing in the display. After debugging I found out that the missing information was not there in the parsed result either. Was there a bug in the XML parser? I debugged that too, but could not find anything that was wrong. Yet when I made the same search in the browser the information was there in the result.

And then I found it! It turned out that my app was searching not today's date, but a month ago. Most of the information was the same, but some was missing. The reason for this was that I pretty late in the project removed the ASAP I had used before and instead used a date field, automatically filled in with a date, that should have been today's, but was actually a month ago.

And the reason for this is how Android Calendar work:

  • calendar.get(Calendar.MONTH) will get you the month number where January is month zero
  • calendar.get(Calendar.DAY_OF_MONTH) will get you the day of the month, where the first day is one
Not very intuitive, even if I assume ther is some logic in it. Anyway, a quick bugfix and new upload to Google Play means that very few users, if any, have been affected.

Saturday, May 10, 2014

New app published

Today I published a new app on Google play: Skåne Transport

It is an app for Local Transport in my home region, Skåne in the south of Sweden. It helps you find trains and busses (and perhaps ferrys) when travelling in Skåne and to adjacent regions like Copenhagen, Göteborg etc.

From a user perspective I have had two goals for the app:

  1. It should be easy to search. You should be able to do most of your searches without typing. I do this by keeping history, making it easy to add favorites and having a preloaded list of the most important stations with the app when it is installed. The user also has the option to use her current location.
  2. The information should be as accurate as possible. If I have information about delays, the app shows te delayed time rather than the one from the timetable (colored in red so that it should be clear for the user that there is a delay)
I'm pretty satisfied with the result. Let's see what the users think.

Sunday, June 12, 2011

First Android app published

Yesterday I published my first Android app on Android market, UnSilence. The background is that I tend to forget to turn my cellphone back to normal after I've set it to silent during a meeting. I have missed too many calls beacuse of that...

So UnSilence helps you be allowing you to set your phone to silent (with or without vibaration) for a period of time, and then automatically turn sound back on.

The main design goal was too keep it simple, one click to start the app, and one click to set to silent, that's all.

Friday, March 18, 2011

Servlet http proxy

For a while I have been working on a project where we are trying to integrate a windows-based service in a Java EE environment. Basically the problem is to host an Ajax application under an application server like IBM Webspehere or Apache Tomcat. We also want to support portlets following the JSR 268 specifikation.

I googled around a bit and found lots of useful stuff, but nothing that did all that we wanted. The mainly problems was with headers and cookies, since we need to keep a session to the servicein the background we need to make those work. So I ended up writing my own. Not much code, but it might be useful for someone else, as it is pretty general stuff.

The service method

Since we want to handle all HTTP calls, we override the service method of HttpServlet. If you want only some methods (GET and PUT for example) to work you might just override doGet and doPost for example, but we want it all.. The implementation looks like this:
protected void service(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
String qry = req.getQueryString();
URL url = new URL(protocol, host, port, req.getRequestURI()
+ (qry == null ? "" : "?" + qry));
HttpURLConnection urlConnection = (HttpURLConnection) url
handleRequestHeaders(req, urlConnection);
handlePostData(req, urlConnection);
// make the call - get response code
int responseCode = urlConnection.getResponseCode();

if (responseCode != HttpURLConnection.HTTP_OK)"HTTP code:" + responseCode + " "
+ urlConnection.getResponseMessage() + " URL["
+ url.toString() + "] " + req.getMethod());
log.debug("HTTP code:" + responseCode + " URL[" + url.toString()
+ "] " + req.getMethod());
handleResponseHeaders(resp, urlConnection);
// send output to client
handleContent(resp, urlConnection, responseCode);

This is pretty straight forward. The protocol (http/https), server and port to use are configurable. We take the URI from the request and add the query string, if there is one. Together with the configure host etc, this forms the new URL, which we open, using the same method as in the call. We set some parameters, request headers and post data if there is any.

We then call the URL, check the HTTP response code, and take care of the headers and the response, which all are sent to the client.

Handle headers
The part that we really needed was the headers. This simply transfers the headers between the two connections, with a few exceptions:

private void handleRequestHeaders(HttpServletRequest req,
HttpURLConnection urlConnection) {
// set request headers
Enumeration e = req.getHeaderNames();
while (e.hasMoreElements()) {
String key = (String) e.nextElement();
if (!"Host".equalsIgnoreCase(key)
&& !"Accept-Encoding".equalsIgnoreCase(key)) {
String value = req.getHeader(key);
log.debug("Request Header: " + key + ": " + value);
urlConnection.setRequestProperty((String) key, value);
//add your own headers here

There are two headers that we dont want to transfer from the client's request to our new request:
  1. The Host header, since this will be our proxy server. The new Host header will be added automatically, so we don't need to think about it.
  2. The Accept-Encoding header. This is a fix, the Accept-Encoding header turns gzip on, and since we have not implemented gzip in our proxy we don't want it. Another alternative would be to turn gzipping of requests off in our web server, perhaps this would have been better. If we do transfer th Accept-Encoding header, both servers might zip the content, which will not work.
Finally in this method we add our own headers, which is basically the reason why we need the proxy at all.

When we get the response back from the server we have the corresponding method to handle the response headers:

private void handleResponseHeaders(HttpServletResponse resp,
HttpURLConnection urlConnection) {
// set response headers
Map<string,>> headers = urlConnection.getHeaderFields();
Set<map.entry<string,>>> entrySet = headers.entrySet();
for (Map.Entry<string,>> entry : entrySet) {
String key = entry.getKey();
List<string>> headerValues = entry.getValue();
for (String value : headerValues) {
if (key != null && !"Server".equalsIgnoreCase(key)) {
log.debug("Response Header: " + key + ": " + value);
resp.addHeader(key, value);

This is basically the same as the request headers. In this case we just filter the Server header, where our proxy application server will add its own name.

Finally to set it up in web.xml we configure the URLs we want the proxy to handle, set the protocol, host and port and we are ready to go.

Thursday, September 09, 2010

NoClassDefFoundError in BlackBerry

I have been struggling a few days with a strange error in BlackBerry. My app works fine in the emulator, but when you start it on BlackBerry Bold (software version 4.5) you get a NoClassDefFoundError. On BlackBerry Storm (software version 4.6) it works fine, but on Bold2 (version 5.0) again you get NoClassDefFoundError.

The documentation says:
Thrown if the Java Virtual Machine tries to load in the definition of a class (as part of a normal method call or as part of creating a new instance using the new expression) and no definition of the class could be found.

The searched-for class definition existed when the currently executing class was compiled, but the definition can no longer be found.

I have gone through all the changes since the last working version and I finally found it. I had added some fields like this:

fldPortHttp = new TextField("Port:", "", 20, Field.EDITABLE | BasicEditField.FILTER_NUMERIC);

This worked well, with no compilation errors and in the emulator, but caused the NoClassDefFoundError at runtime. The solution was simply to change to:

fldPortHttp = new BasicEditField("Port:", "", 20, Field.EDITABLE | BasicEditField.FILTER_NUMERIC);

Sunday, May 09, 2010

The future for mobile java

The last three years or so I have worked mostly with mobile java, starting with Java ME and later moving into BlackBerr and Android. A lot of things has happened, three ears ago Android existed, but ther were hardly any phones available and BlackBerry did exist, but I knew nothing about it.

Today the future of Java ME is uncertain. Programming in Java is a good option on most mobile platforms (except iPhone), but the strongest alternatives are Android and BlackBerry, not Java ME.

There are of course different reasons for this. On the technical side, the User Interface options are very limited. LCDUI is very restricted, you very quickly end up with skipping the higher level API, because it is too restricted, and using the Canvas API, where you basically have to paint everything yourself. Doing input in a canvas based interface is difficult, you can react on key down and up, but the standard does not really allow you to tell if the devices even has a keyboard, or if you need to display a virtual keyboard on the screen.

An even worse problem is the fragmentation of the market. Java implementations differ, and even if it is very probable that your java me code will run on most devices (if it is well written) verifying that it does is not a smal task. And if you want it too look good it is even worse. Emulators do not help much either, verifing that something runs in the emulator does not guarantee that it will work on the device. And it is not even sure that there is an emultor for your target device.

And phone manufacturers keep making new models all the time... Apple basically has one platform and offers upgrade for old versions (sometimes free of charge, sometimes at a small charge) but the competition has not learned from this. Instead they have incompatible version on different devices, where you basically have to test on, if not all, several different versions. Just keeping up with the new models from the main manufacturers ( there are only four or five) takes a lot of time. The so called java verification does not guarantee that your application will run on all Java ME implementations with the features you need, instead you have to verify it again and again as there are new devices.

All in all this leads to that Java ME is not a good alternative for your application development today. The future of java om the mobile is rather in Android or BlackBerry. That is if not one of the major manufacturers take steps to fix this. And frankly I don't see this happening.

An exception to this is possibly Symbian. Java ME implementation on Symbian is pretty good. But it seems like Nokia is more interested in promoting development in C++, or rather the very restricted C++ available on Symbian.

Wednesday, January 06, 2010

New Antenna release

Today I released version 1.2.1 of Antenna. The new version includes both bug fixes and new features.

I made a mistake in the 1.2.0 release, which leads to a Null Pointer Exception if the Wireless Toolkit can not be detected. Antenna can detect a lot of toolkit's, but not all, so this has given users some poblems. A patch has been in the repository for a whil, but now it is in a release also.

When the 1.2.0 release was made, ther was no Java ME SDK for Mac available, but now there is. Unfortunately the file we used in 1.2.0 to detect Java ME SDK 3.0 is not included in the Mac version, so toolkit detection fails. This is fixed in the 1.2.1 release, which should work with Java ME SDK for Mac ( I haven't tested it myself, since I don't have a mac).

The realease also includes som contributed patches:
- obfusactor arguments can now be passed to WtkPackage
- Key stor type can be set in WtkSign
- WtkRapc can build libraries

More info on antenna and the release is available here.

Friday, January 01, 2010

Supporting BlackBerry touch devices

Our BlackBerry application is built using BlackBerry software version 4.5. Unfortunately this means that we can not handle touch events, since they are only supported from version 4.7. Since most of our users have 4.5 or 4.6 this is not an option. Up til now the application has had very limited functionality on touch devices like BlackBerry Storm, running in the so called *compatibility mode' with the virtual keyboard displayed all the time and only about half the screen available for our application.

But now we have made a few changes:
We upgraded the Storm device software (to version This solved the problem with the virtual keyboard, which now can be displayed only when needed.

We revised our application. The main problem is our custom object, which did not work well. This seems to be because the navigationMovement method is not called on a touch device. Since we had some application logic in this method in our custom object, it did not work well. The solution was to move the code to the moveFocus mthod, which is called both on touch and keyborad devices.

In the long run we probably will have to provide different installations for users with 4.5/4.6 or 4.7 software version. Still we do not support more advanced touch screen usage.

Sunday, September 27, 2009

Antenna 1.2.0 with support for Java ME SDK 3.0 released

Yesterday I made the new antenna version with support for Java ME SDK 3.0 available for download. The testers have been positive so far, so it is ready for more general use.

The changes are documented in here. You will also find the matrix with toolkits ad optional libraries there, it seems like Blogger don't really like my html table...

The download is available here.

Wednesday, September 23, 2009

Java Me toolkit's and support for optional JSR's

As a part of the new Antenna release I have reviewed the toolkits supported and which JSR's they support. The result is the matrix below.

As you see, many JSR's are widely supported, while others are supported only by a few manufacturers. If you need Bluetooth, PDA, Wireless Messaging, SVG or Mobile Media, they are available in most emulators. But if you need Internationalization, or Open GL your choice is more limited.

Many manufacturers have their own additional APIs. Most used is Nokia UI, which is actually also supported by Sony Ericsson.

JSR API SupportAntenna propertySun WTK 2.5Java ME SDK 3.0MOTODEV Studio for Java MENokia S60 3rd Edition SDKNokia N97 SDKNokia S40 5thedSony Ericsson SDK 2.5Sprint WTK 3.3.2LG SDK 1.3 for Java ME
CLDC version1.0,1.11.0,, 1.11.0, 1.11.0, 1.11.0, 1.1
MIDP version
JSR 75 PDAoptionalpdaxxxxxxxxx
JSR 82 BluetoothBluetoothxxxxxxxxx
JSR 135 Mobile Media 1.2mmapixxxxxxxxx
JSR 172 Web Servicesj2mewsxxxxxxxxx
JSR 177 Security and Trust Servicessatsaxxxxxxxxx
JSR 179 Locationlocationservicesxxxxxxxx
JSR 180 SIPsipapixxxxxxx
JSR 184 Mobile 3D Graphicsjava3dxxxxxxxxx
JSR 120 WMA 1.0wmaxxxxxxxxx
JSR 205 Wireless Messaging 2.0wma2xxxxxxxxx
JSR 209 AGUIaguix
JSR 211 Content Handlercontenthandlerxxxxxxx
JSR 226 Scalable 2D Vector Graphicss2dvgapixxxxxxxxx
JSR 229 Paymentpapixxxxx
JSR 234 Advanced Multimedia Supplementsamsxxxxxxxxx
JSR 238 Mobile Internationalizationmiapixxxxxx
JSR 239 Java Binding for OpenGL ESopenglxxxxx
JSR 256 Mobile Sensormobilesensorxxx
JSR 257 Contactless Communicationrfidx
JSR 280 XMLxml

JSR 300 DRMdrm



Motorola APIsmotorola


Nokia UI APInokiaui


eSWT APIeswtx
IAP Infoiapinfox

Saturday, September 19, 2009

Antenna: Support for LG SDK 1.3 for Java ME and Nokia N97 SDK

Today I added support for LG SDK 1.3 for Java ME and Nokia N97 SDK to antenna. This is available now in the repository and hopefully soon as a binary download.

Wednesday, August 26, 2009

Antenna Java ME SDK 3.0 version now available

My patch for antenna is now comitted into the repository and is available for download. Still no build available, you have to get the sourcecode yourself and build it, or send me a mail and I will send you a jar file. Hopefully the pre-built version will be available soon. Documentation is also not updated yet, but you will find some in this blog.

Wednesday, July 08, 2009

Antenna support for Java ME SDK 3.0

For building our Java ME application we use Antenna. It is a great tool, that makes automated builds possible and also works well as your regular build tool. But it lacks support for Java ME SDK 3.0 and other newer toolkits. Since we need that, I have made a contribution to the Antenna project, added as a patch yesterday.
If you want to try the modified verions, send me a mail and I will send you the jar.

How it works

A key property of your Antenna setup is the wtk.home property. It should point to the base directory of your WTK/Java ME SDK installation. Antenna uses this to detect which toolkit you are using. In the older version toolkits are hardcoded into Antenna sourcecode. In the new version textfiles are used to set up available toolkits and their properties. Antenna goes through a list of toolkits, described in the text file autodetect.txt, and checks if the unique files for that specific toolkit are available. If they are, the right toolkit have been found, and properties are loaded from a properties file.

This makes it easy to add a new toolkit or new properties for the existing one.

Supported toolkits

I have tested the new version with the following toolkits:
- SUN Java ME SDK 3.0
- Sun WTK 2.5.2
- MOTODEV SDK for Java ME v2
- Nokia S60_3rd_FP2_SDK_v1.1 (Symbian)
- Samsung_SDK_11 (autodetected as WTK 2.5.2)
- SonyEricsson WTK 2.5.2
- Nokia S40 5th Edition SDK Feature
Pack 1

I have also made some tests with Mpowerplayer, but the stub for CLDC 1.1 provided with Mpowerplayer seems not to match the specification. If I replace it with the one from Suns WTK 2.5.2 it seems OK. I have not tested Mpowerplayers preverifier, since it is Mac based and I use a Windows PC.

Antenna setup

Antenna properties are described here. They work as before, with the new feature that additional libraries can be defined dynamically, in the toolkit properties file, without any need for changes in Antenna source code. If I set up a property for a toolkit like this:


I can then turn it on in my ant file by setting the property wtk.jsr199.enabled to true. I can also turn on all defined additional libraries by setting property wtk.all.enabled to true. During development I used this, since Antenna checks that all jar files are available.

Adding a new Toolkit
You can add a new toolkit to antenna just by editing a text file and adding another. Do like this:
First you add a new line to the file autodetext.txt (in the res directory). It should look something like this:

#sony ericsson

Lines starting with # are comments. The lines defining toolkits should start with the toolkit property filename and then contain a list of files that are unique to this toolkit. File names should be relative to wtk.home.

Then you add a properties file, in this case It looks something like this:

name="Sony Ericsson WTK2"

The properties you could use are:

  • name: a descriptive name for the toolkit. Use this always.
  • preverifyversion: 1 means WTK 1 style, support only CLDC 1.0, 2 means WTK 2 style, include Target parameter in preverify command, 3 means WTK 3 style, only add parameter cldc1.0 if cldc 1.0 is used
  • emulator: exe or jar file for emulator
  • cldc10,cldc11: libraries for cldc versions
  • midp10,midp20,midp21: libraries for midp versions
  • include: include another toolkit definition. Useful if the toolkit is an add-on to another toolkit, like WTK 2.5 or Java ME SDK 3.0
All other properties will be taken for add-on libraries that will be added to classpath if wtk.[propertiy].enabled is true, or if wtk.all.enabled is true.

Please let me know if you have any problems or improvement suggestions.

Tuesday, June 30, 2009

Catch System.out from BlackBerry simulator

Just a little trick I just learned. Sometimes I want a quick and easy logging, just to see what's happening in my program. The easiest approach, specially early in the project is simply using System.out. But when you run your program in the emulator you don't see system out anywhere. To see it you need the command line parameter /app-param=JvmDebugFile.

Just run the emulator as follows:

fledge /handheld=9000 "/app-param=JvmDebugFile:bblog.txt"

In the bblog.txt you will get a lot of info, and your System.out output.

Wednesday, June 17, 2009

Java ME automated build

So far I have built my Java ME application using Sun Java ME SDK 3.0 and before the SDK was available with Sun Wireless Toolkit. But now we need to streamline the process and introduce automated build.

The tool we use for this is ant, with an add-on for Java ME called antenna. Antenna is an open source project, which provides support for operations like obfuscating, updating manifest and JAD files and signing.

To use antenna you need to setup the antenna tasks, using taskdef, and define some properties:

<taskdef resource="" classpath="${basedir}\tools\antenna.jar" />
<property name="wtk.home" location="C:\WTK2.5.2"/>
<property name="wtk.cldc.version" value="1.1"/>
<property name="wtk.midp.version" value="2.0"/>
<property name="wtk.proguard.home" value="${basedir}\tools\proguard4.3"/>

As you can see, we have a directory called tools, where we keep the antenna jar and also a proguard installation, which we need for obfuscation.
Antenna also needs to know where your wireless toolkit is installed and which versions of CLDC and MIDP you use. That's it!

Antennas main function is packaging your application into jar and jad files, preverified, obfuscated and with correct manifest and jad files. You can do this step-by-step, with different tasks for each step, but you can also use the wtkpackage task to make them all.This is the approach we have taken.

<target name="package" depends="compile">
<mkdir dir="${dist.dir}"/>
<copy file="${basedir}/myapp.jad" overwrite="true" failonerror="true" tofile="${dist.dir}/myapp.jad"/>

<wtkpackage jarfile="${dist.dir}/myapp.jar"

<fileset dir="${class.dir}"/>
<fileset dir="${res.dir}"/>

<exclude_from_manifest name="myapp-dir"/>
<exclude_from_manifest name="myapp-host"/>

<copy file="${dist.dir}/myapp.jad" overwrite="true" failonerror="true" tofile="${dist.dir}/myappu.jad"/>


  1. compilation is separate, our package task is made after the compilation
  2. we keep a jad template in the project basedir, which we copy to the dist dir
  3. wtkpackage will create the jar file and update the jad file. We also want it to preverify and obfuscate using proguard
  4. in ${class.dir} we have all classes that should be included
  5. all used resources are in ${res.dir}
  6. we have two parameters in our JAD template that should be only in the JAD file and not in the Manifest file. This allows for changing them without resigning.
  7. as a last step we copy the jad file. This is to have an unsigned copy for use in emulators and phones that don't support the Verisign certificate we use (Nokia S40..)
Signing the application
Antenna also supports signing using the very straightforward wtksign task:

<target name="sign" depends="package">


This will add signature information to the JAD file using the certificate in the keystore and the JAD and jar files are redy to use.

Wednesday, June 03, 2009

Going native on BlackBerry

Our application is currently based on Java ME and uses the lcdui to a 100%, even though there are some fixes to make it work better on BlackBerry. Since BlackBerry is getting more and more popular in the market we have decided to make a version that uses the BlackBerry native UI instead of Java ME standard lcdui.

BlackBerry does not allow combining its native UI with lcdui, which means we will have to convert everything, including the midlet. The majority of the code is however in our own classes, since 90% of tha application is Canvas-based. It seems quite possible to make them work in both environments.

Major changes will be:
- our midlet is replaced by a UIApplication
- the Canvas will be replaced by a MainScreen
- instead of the List we use we will have a KeywordFilterField, which will gives the users better functionality.

Our components will be placed in the MainScreen (instead of a Java ME Canvas). To make this work we will use an interface for painting with two different implementations, that encapsulate Java ME Graphics and BlackBerry Graphics. We will also need to handle the different Font classes and lcdui Image versus BlackBerry Bitmap.

Our immediate gains will be:
- scalable fonts, which is a problem for us now, since the Lcdui fonts on BlackBerry Bold are very large
- some UI improvements, like the KeyWordFilterField instead of the List etc
We will also gain access to possiblities like opening an input field on top of ouyr Canvas, with we really need and have a better looking app.

Tuesday, May 05, 2009

Java ME Search Engine

Finding information on Java ME issues can be time consuming. A lot of information is available on the Internet, and Google finds lots of it. But most of the time you get Java ME information mixed with a lot of Java SE information.

To solve this I have collected a lot of Java ME resources and created a Google customized Search Engine. This is a first try, based on some links I had collected. There is certainly a lot more resources available out there. If you know one, don't hesitate to send me a mail.

Here is the search box: