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POAttempt to set model object on null model of component
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  1. POAttempt to set model object on null model of component
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    copied!<p>I'm new to Wicket, but googling this problem didn't give me anything that made sense. So I'm hoping someone in SO can help.</p> <p>I have a SiteChoice object that extends Form, and a SiteList object that extends DropDownChoice. My SiteChoice class looks like:</p> <pre><code> public class SiteChoice extends Form { public SiteChoice(String id) { super(id); addSiteDropDown(); } private void addSiteDropDown() { ArrayList&lt;DomainObj&gt; siteList = new ArrayList&lt;DomainObj&gt;(); // add objects to siteList ChoiceRenderer choiceRenderer = new ChoiceRenderer&lt;DomainObj&gt;("name", "URL"); this.add(new SiteList("siteid",siteList,choiceRenderer)); } } </code></pre> <p>Then I simply add my SiteChoice object to my Page object a la:</p> <pre><code> SiteChoice form = new SiteChoice("testform"); add(form); </code></pre> <p>My Wicket template has: </p> <p>When I bring up the page, it renders fine -- the drop-down list is correctly rendered. When I hit Submit, I get this strange error:</p> <pre><code>WicketMessage: Method onFormSubmitted of interface org.apache.wicket.markup.html.form.IFormSubmitListener targeted at component [MarkupContainer [Component id = fittest]] threw an exception Root cause: java.lang.IllegalStateException: Attempt to set model object on null model of component: testform:siteid at org.apache.wicket.Component.setDefaultModelObject(Component.java:3033) at org.apache.wicket.markup.html.form.FormComponent.updateModel(FormComponent.java:1168) at [snip] </code></pre> <p>I can't figure out what is null. It rendered fine, so it found the objects. What am I missing?</p>
 

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