New JavaFX Control PlusMinusAdjuster

Today I had once again the pleasure to write a small and highly specialized control for JavaFX, which might be useful for others as well. I am calling it PlusMinusAdjuster and all it does is firing value events with values ranging from -1 to +1. The difference to a normal slider is that it continues to fire events even when the value has not changed. This kind of behavior is useful for implementing scrolling through large data sets. A normal scrollbar often causes big jumps even when the user only moves it a few pixels. For me this was the case for my Gantt chart component when the timeline horizon was very large and the currently visible time span was small.

So this is what I came up with:


I have asked the ControlsFX guys if they are interested in including this control. The initial response was positive. I will keep you updated.

Collapp: First Release / Looking for Testers

I finally managed to release a first version of Collapp, a solution for collaborative project planning, and now I am looking for testers / early adopters. I have been working on it on and off for the last couple of years. In part to learn more about JEE and in part to continue work on FlexGantt (online demo), a framework for creating Gantt charts.

I believe that I have now reached a point where a bigger group of people could take Collapp for a ride. Anyone interested can now try the online demo or download the full installation. The online demo allows you to register a new user account and get immediate access to the application. If you also want to see the administration features then please send me an email so that I can grant you the required permissions.

Collapp is a JEE (rich) client / server solution running on the Glassfish application server and the MySQL database. The screenshots below show what it looks like when running it on a Macintosh (note: use Java 6, not 7) and on Windows.

Collapp Macintosh Snapshot

The first release focuses on the management of so-called “Action Items” only. It does not contain any actual project planning functionality, yet (e.g. a Gantt chart, Work Breakdown Structures, Resource Calendars). I decided to go with this approach in order to get to a point where the application reaches production quality for at least some part of its functionality. Project planning will eventually be based on the action item feature as project tasks will result in action items that are assigned to individual team members.

A strong emphasize of my work was on the Macintosh UI of Collapp. I tried to come up with a user experience that is as close to native Mac apps as humanly possible. I would love to get some feedback on whether I was successful or not. For Windows I picked a more liberal approach by using the commercial BizLaf look and feel framework from Centigrade.

The Macintosh download also contains the standalone rich client, so that you don’t have to answer any annoying Java Webstart security questions. There currently is no Windows standalone client.

To read more about Collapps feature set, please check out these links: