This mail is originally from wicket-user, but I reply here to get more attention.
This looks pretty elegant way to do the thing. Any objections before I commit this into the trunk? Janne On Sep 23, 2006, at 4:50 PM, Joni Freeman wrote: > Some months ago there were discussion about how to use immutable value > objects in wicket. See: > http://thread.gmane.org/gmane.comp.java.wicket.user/12887/focus=12887 > > The conclusion was that wicket does not support well such a case > currently (http://article.gmane.org/gmane.comp.java.wicket.user/ > 12911). > However, I think there may be pretty easy way to solve the issue. > Provide a FormComponent which can use associated markup file, just > like > a Panel: > > public abstract class CompoundFormComponent extends FormComponent > { > private boolean wasOpenCloseTag = false; > > public CompoundFormComponent(String id) > { > super(id); > } > > public CompoundFormComponent(String id, IModel model) > { > super(id, model); > } > > @Override > public abstract void updateModel(); > > @Override > protected void onComponentTag(final ComponentTag tag) > { > if (tag.isOpenClose()) > { > this.wasOpenCloseTag = true; > > // Convert <span wicket:id="myPanel" /> into > // <span wicket:id="myPanel">...</span> > tag.setType(XmlTag.OPEN); > } > super.onComponentTag(tag); > } > > @Override > protected void onComponentTagBody(final MarkupStream markupStream, > final ComponentTag openTag) > { > // Render the associated markup > renderAssociatedMarkup("panel", > "Markup for a panel component has to contain part > '<wicket:panel>'"); > > if (this.wasOpenCloseTag == false) > { > // Skip any raw markup in the body > markupStream.skipRawMarkup(); > } > } > } > > Note, the methods onComponentTag and onComponentTagBody are copy > pasted > from Panel. The method updateModel() is made abstract, this is the > place > where the immutable value object is created from convertedInputs of > FormComponents. Now, the IntegerRangeField (see the original > thread) can > be written simply as: > > IntegerRangeField.java: > > public class IntegerRangeField extends CompoundFormComponent { > private final TextField minimum; > private final TextField maximum; > > public IntegerRangeField(Form parent, String id, > IModel/*<IntegerRange>*/model) { > super(id, model); > minimum = new RequiredTextField("minimum", new > Model(defaultMinimumValue()), Integer.class); > maximum = new RequiredTextField("maximum", new > Model(defaultMaximumValue()), Integer.class); > add(minimum); > add(maximum); > parent.add(new Validator(this)); > } > > @Override > public void updateModel() { > setModelObject(new IntegerRange( > (Integer) minimum.getConvertedInput(), > (Integer) maximum.getConvertedInput())); > } > > private Integer defaultMinimumValue() { > if (rangeValue() == null) { > return null; > } > return rangeValue().getMinimum(); > } > > private Integer defaultMaximumValue() { > if (rangeValue() == null) { > return null; > } > return rangeValue().getMaximum(); > } > > private IntegerRange rangeValue() { > return (IntegerRange) getModelObject(); > } > > public static class Validator extends AbstractFormValidator { > ... > } > } > > IntegerRangeField.html: > > <?xml version="1.0" encoding="utf-8"?> > <wicket:panel> > <table cellpadding="0" cellspacing="0" border="0"> > <tr> > <td> > <input wicket:id="minimum" type="text" class="text numeric" > size="8" /> > </td> > <td> - </td> > <td> > <input wicket:id="maximum" type="text" class="text numeric" > size="8" /> > </td> > </tr> > </table> > </wicket:panel> > > I tried this with other immutables too, like DateRanges etc. and the > implementation was always straight forward. The original > implementations > were much more complex and required deep knowledge of wicket's form > processing. It would be great to see something like this in core since > the abstract CompoundFormComponent contains copy pasted code from > Panel. > > Joni > > > > ---------------------------------------------------------------------- > --- > Take Surveys. Earn Cash. Influence the Future of IT > Join SourceForge.net's Techsay panel and you'll get the chance to > share your > opinions on IT & business topics through brief surveys -- and earn > cash > http://www.techsay.com/default.php? > page=join.php&p=sourceforge&CID=DEVDEV > _______________________________________________ > Wicket-user mailing list > Wicket-user@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/wicket-user ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys -- and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Wicket-develop mailing list Wicket-develop@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/wicket-develop
