ClassNotFoundException with the new Java design element

Last week Vince Shuurman blogged about having to recompile when opening an XPage app in Domino Designer.

I had the same issue. I was using some Java code in an XPage, and every time I opened the app in designer, I got ClassNotFoundException when opening the XPage. A build of the project fixed the issue.

My java code was in the new Java design element (new in Domino 8.5.3), so I suspected that it might have something to do with this.

I moved the code to a "custom" java source folder, and the error went away. Closing/opening the app in Designer did not result in ClassNotFoundException.

Java Debugging in Designer without hacks

I found this today: How can I enable Java debugging?.

Not sure if this is new in 8.5.3, but I never heard of it. It makes it a lot easier to debug than the using the two headed beast method which seemed like too much trouble.

The full instructions are in the Designer help. Search for java debugging.

Collecting data for HTTP hang or performance issues on a Lotus Domino server

We're currently having problems with one of our old Domino servers. The HTTP task randomly hangs.

In the process of looking for help to track down the reason, I found this document from IBM.

Collecting data for HTTP hang or performance issues on a Lotus Domino server

Indicator for all partial refreshes

Sometimes partial updates take a while. To make users aware of updates happening, I made a small JS object that automatically shows a dojox.widget.Standby over the area being updated. Initially I thought that it would be too much, showing the mask over every refreshed area. So far, I quite like the effect.

The app isn't in production yet, so I don't know how users will react, but hopefully they will appreciate being made aware of that things are happening.

To load the object, put this in a JavaScript library (client side)

dojo.addOnLoad(function(){ new StandbyWidget(); });

The default background color is bright yellow. To override, simply put a hex string in the "constructor" call.

dojo.addOnLoad(function(){ new StandbyWidget( '#555'); }); // Dark grey

To use the code snippet below, you also need the partial event hijacker

var StandbyWidget = function( backgroundColor ){
 dojo.require( 'dojox.widget.Standby' );
 this.widget = new dojox.widget.Standby();
 this.widget.attr( 'color', backgroundColor || '#ffe' );
 
 document.body.appendChild( this.widget.domNode );
 this.widget.startup();
 
 dojo.subscribe( 'partialrefresh-init', this, function( method, form, targetId ){
  if( targetId && targetId !== '@none' ){ this.show( targetId ); }
 });
 
 dojo.subscribe( 'partialrefresh-complete', this, function( method, form, targetId ){
  if( targetId && targetId !== '@none' ){ this.hide(); }
 });
 
 dojo.subscribe( 'partialrefresh-error', this, function( method, form, targetId ){
  if( targetId && targetId !== '@none' ){ this.hide(); }
 });
}

StandbyWidget.prototype = {
 show: function( targetId ){
  this.widget.attr( 'target', targetId );
  this.widget.show();  
 },
 hide: function(){  
  this.widget.hide();
 }
}

Using themeId for maintainability

In an application I'm currently working on, there are several categorized views with number-/totals columns. As the number of views/columns increased, I looked for a way to make styling of the columns more maintainable.

The solution I found was using themeId on the columns and calling a SSJS function in the theme, that generates the style classes.

I chose numberColumn as the name for the themeId.

In theme

<control>
 <name>numberColumn</name>
 <property>
  <name>styleClass</name>
  <value>#{javascript:return StyleHelper.getNumberColumnStyleClass( this );}</value>
 </property>
</control>

this refers to the column object.

SSJS code

var StyleHelper = {
 // Used to calculate styleClass for a number column
 getNumberColumnStyleClass: function( column ){
  try {
   var entry = column.getViewRowData();
   var styleClass = 'numberCell';
   if( entry.isCategory() ){ styleClass += ' categoryCell'; }
   if( entry.isTotal() ){ styleClass += ' totalsCell'; }
   return styleClass;
  } catch( e ){ /* Exception handling */ }
 }
}

Regular column cells will get class="numberCell".
Totals column cells will get class="numberCell totalsCell".
Category column cells will get class="numberCell categoryCell".

All I have to do to add dynamic styling to future columns is to set themeId on the column to numberCell.

XPages: Passing event handler code to custom control

Update: After a little test, it looks like the onchange event of the combo fires for every refresh. I'll move the code to beforeRenderResponse or something like that instead.

In an application I'm currently working on, I have a combobox that's used in several pages. The values the combobox contains persist over every page, but what happens when the user changes value varies from page to page.

I saw that the combobox has several properties for events under all properties. I tried adding
#{compositeData.onchange} to the onchange event, and it works. One caveat is that it seems to fire three times, but I can live with that.

To implement:
Add custom properties to the custom control for the events you want to have custom event handlers for. In the source code of the field, add attributes for the events you want code to run. E.g. onchange="#{compositeData.onchange}"

In the XPage under custom properties for the custom control, write the SSJS you want to run for your events.

That's about it.

I have only tested this with ComboBoxes, but I'm not surprised if it works for most fields that have event properties.

Tested on server running Domino 8.5.2 FP2