JasperReports/iReports dynamically show and hide fields conditionally

Introduction

With JasperReports and its visual designer iReports you can have (blocks of) fields collapse based on certain conditions.
You can use a subreport, but that's not necessary. This post describes how to show/hide fields without subreports.

How

Basically you have to do two things:

1. Put the elements (static text, textfields etc) you want to hide on a frame. Make sure the fields are not behind the frame.
2. Set the correct properties on the frame, including the expression to show/hide it dynamically. By hiding the frame you hide all the fields on it. 

The most important thing is to make sure no other element besides those that need to be on it is overlapping with the frame! Below is a screenshot to make it clearer.
There are three static and three textfields on the frame. Plus two (separate!) vertical lines.

Note the green, red and black vertical lines in the screenshot: the red and black vertical lines are not on the frame at all. The frame has its own green vertical line. That way JasperReports can shrink it based on the condition. Otherwise it doesn't know what to do with the overlap, and doesn't (can't?) collapse it. Notice also the frame is selected (little square blue boxes on its lines) to make clear from where to where the frame runs.
So basically you have to make sure the frame is all by itself, all its elements only on the frame, and no other elements overlapping the frame.

PS: it might be possible to do it per field, but since I needed at least a label + field to be shown/hidden, I didn't even try that.

To put in the other necessary settings, you have two ways of doing that:

1. Via the XML:
   
   Put in the condition of the frame. So if theObject is not null, the frame will be shown. Also make sure you add 'isRemoveLineWhenBlank="true"'. E.g:
   
   
2. Or via the Eclipse properties tab: see below screenshot:
   
   
   
   
   Notice setting the flag and the expression, see the arrow pointing at $F, that's the start of the same above expression in the XML.

Refactor/rename package in Eclipse with Subclipse and SVN

Refactoring a package by giving it a new name can give quite annoying problems when trying to commit it from within Eclipse using the Subclipse plugin.

You can get (tree) conflicts, maybe even causing you to rollback all your changes and then step by step committing them.

Below is a set of steps you can follow that should not cause any problems if executed in this order :) In short: you do your refactor, then first commit only the deletions, and only then commit the additions (which are the moved files in their new package location).

Detailed steps

Set up and tested with: Eclipse Juno version, Subclipse plugin, SVN 1.6:

1. Rightclick on your project and select Team --> Synchronize with Repository
2. Select the incoming view
3. Now note in the incoming view, it shows conflicts on some/most directories (packages) that were renamed. Just do an update on those.
4. Go to the outgoing view
5. If you now select all items with a '-' (the deleted ones) and then try to commit, you get an error on the commit: Tree remains in conflict. Notice the red/green icons on several directories (actually the ones that had a conflict in step 3), see screenshot:
   
   
   
   So those need to be resolved first.
6. Right click on one of those entries (multiple select not supported for the Show Tree Conflicts operation) and select Team --> Show Tree Conflicts. That shows something like:
   
   
   
7. Rightclick and select Resolve...
8. On that next screen:
   
   
   select only Mark conflict resolved.
9. Click Finish
10. Now the entry is not marked red/green any more, and only shown with a '-' in the Synchronize screen! 
11. Do that for all red/green arrows (conflicts)
12. When done, right-click on all items marked with a '-' and select Commit. And that succeeds!
13. Finally, commit now the ones marked with '+' (so the added ones)
14. Really final step: note that sometimes some empty packages with the old name stay around. Deleting them in Eclipse and then trying to commit gives again conflicts(!). Those I just delete directly from the Repository perspective and do an update on those.

Bonus tip: sometimes when another team member has commited a new module, the Synchronize perspective will show the (compiled) /target dir and its items as needing to be committed. Even though the directory is already in the .svnignore file, since right-clicking on it won't allow you to add it. Solution: do an update on that target directory. After this it should be fine and it should not show up anymore on the next Synchronizes.

Best of this Week Summary 26 July - 1 August 2010

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  Great reference in the comments for fast-change+ctrl-s+reload-browser experience with Weblogic FastSwap and Oracle Enterprise Pack for Eclipse.
  


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Best of this Week Summary 31 March - 6 April 2008

• Good explanation on how to integrate Eclipse WTP with Maven2.
  


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Setup and Installation Ubuntu Development Environment with VMWare Part 2

This is the second post in my series on how to setup a development environment on Ubuntu 7.04 (Feisty Fawn) with VMWare 6.02. In this post I'll be detailing how I setup Eclipse 3.3 (Europa), thus with WTP and PDT. I'll also describe my experiences with Europa 3.2 (Callisto), because I tried that too, in case I couldn't get 3.2 working...

Install Sun Java JDK 5

Since I want to use Java 5 in Eclipse, I first installed the JDK via: 'sudo apt-get install sun-java5-jdk', which installs it in /usr/lib/jvm/java-1.5.0.sun. Make sure you use the Java 5 JDK by setting it via "sudo update-alternatives --config java'.

Install Eclipse 3.2 Callisto with WTP

Installation of Eclipse 3.3 is not supported via the repositories. But first I wanted to try to get 3.2 running anyway.
Step 1 - Installation steps Eclipse 3.2 and setup JDK
Substep 1a - Installed Eclipse 3.2 Callisto via 'sudo apt-get install eclipse' and that worked fine.
Substep 1b - I then installed WTP via Eclipse's own Software Updates mechanism. You might want to install it to "/usr/local/lib/eclipse" to make the plugins available for other users. After this, you can find Eclipse 3.2 in the menu Applications/Programming/Eclipse.
Substep 1c - Then set JDK 5 in Eclipse as the one to use (instead of the default GCJ; is not the greatest performance wise apparently).

Install Eclipse 3.2 Callisto with PDT

Apparently it is not really supported, see here and here. So I did try it for a bit but gave up when I found those two statements.

Install Eclipse 3.3 Europa with WTP and PDT

Since I couldn't get it to work with 'get-apt' nor by downloading the .gz, extracting and setting symbolic links to give all users access to it, I followed these steps, which only make it available for the current user:
Step 2 - Installation of Eclipse 3.3 Europa
Substep 2a - Followed the steps in the User Installation section. I used the zip from here.
Substep 2b - Added WTP as I also did above for 3.2. Select what you want. don't forget: expand nodes otherwise 'Get Required' won't search in them!! I also let the plugins installed in the default (Eclipse installation) directory, because we only want the plugins for this special 3.2 version.
Substep 2c - Installed the PDT plugins as described here. It was complaining missing required ODA runtime 1.5.1. To fix that I manually had to select the appropriate checkbox, see screenshot below.

Issues resolved

One problem I was having is that after starting up Ubuntu it always gave the message "There was an error loading the theme Human. Can't open file /usr/share/gdm/themes/Human/Human.xml". I tried changing it in the menu System/Preferences/Themes, but again it showed up. I also tried 'sudo apt-get human-theme', but after reboot the message still appeared. Then I tried removing and adding the feisty themes as mentioned here: 'sudo apt-get remove feisty-gdm-themes' and 'sudo apt-get install feisty-gdm-themes'. Of course I first made a VMWare snapshot before trying this! Actually, the 'remove' said I didn't have the themes installed. And indeed, after a reboot, the message was gone!

Best of this Week Summary 18 February - 23 February 2008

• Nice overview showing how a Ruby on Rails Facebook application named "Friends for Sale" scaled to handle 200 requests/second and 300M page views per month. Includes the used hardware, software, # of visitors etc.
  


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Best of this Week Summary 21 January - 27 January 2008

• Nice routing pattern for webservices that need to provide both synchronous and a-synchronous calls. You can even make the router such that depending on certain criteria (like load, response time), it will either turn the call into an a-synchronous call when needed. Disadavantage of this approach is of course that the caller has to be able to support both an a-synchronous and a synchronous version of each call. Related patterns you can find in these seven Self-Service: select application patterns.
  


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• Summary of a statement made by Bruce Eckel in this article that Java should not change much anymore: it should stop growing and just become stable, and Sun should focus on optimizing/extending the JVM. Interesting considerations.
  


• And finally for this week, for the developers among us, a bunch of shortcut keys in Eclipse you might not know about.
  


• The Open Source hardening Project of the US Homeland Security department together with Coverity has led to the milestone where in 11 opensource projects all main bugs have been fixed. These 11 have been moved up to the new level Rung 2. Here you can see all the results of the scan.