/**
* Called when a null model is about to be retrieved in order to allow a subclass to provide an
* initial model.
* <p>
* By default this implementation looks components in the parent chain owning a
* {@link IComponentInheritedModel} to provide a model for this component via
* {@link IComponentInheritedModel#wrapOnInheritance(Component)}.
* <p>
* For example a {@link FormComponent} has the opportunity to instantiate a model on the fly
* using its {@code id} and the containing {@link Form}'s model, if the form holds a
* {@link CompoundPropertyModel}.
*
* @return The model
*/
protected IModel<?> initModel()
{
IModel<?> foundModel = null;
// Search parents for IComponentInheritedModel (i.e. CompoundPropertyModel)
for (Component current = getParent(); current != null; current = current.getParent())
{
// Get model
// Don't call the getModel() that could initialize many in between
// completely useless models.
// IModel model = current.getDefaultModel();
IModel<?> model = current.getModelImpl();
if (model instanceof IWrapModel && !(model instanceof IComponentInheritedModel))
{
model = ((IWrapModel<?>)model).getWrappedModel();
}
if (model instanceof IComponentInheritedModel)
{
// return the shared inherited
foundModel = ((IComponentInheritedModel<?>)model).wrapOnInheritance(this);
setFlag(FLAG_INHERITABLE_MODEL, true);
break;
}
}
// No model for this component!
return foundModel;
}
public class LazyLoad extends WebPage {
public LazyLoad() {
IColumn[] columns = new IColumn[] {
new PropertyColumn(new Model("col1"), "intValue"),
new PropertyColumn(new Model("col2"), "class") };
ISortableDataProvider dataProvider = new SortableDataProvider() {
public int size() {
return 300000;
}
public IModel model(Object object) {
return new Model((Integer) object);
}
public Iterator iterator(int first, int count) {
return loadEntriesFromDatabase(first, count).iterator();
}
private List<Integer> loadEntriesFromDatabase(int first, int count) {
List<Integer> items = new ArrayList<Integer>();
for (int i = 0; i < count; i++) {
items.add(new Integer(first + i));
}
return items;
}
};
DefaultDataTable t = new DefaultDataTable("t", columns, dataProvider, 3);
add(t);
}
}
(WWB) is a Wicket component toolkit for displaying and editing JavaBeans. Web pages are automatically generated based on bean properties and conventions. If necessary, the layout, editability, and actions of these pages can be customized. At the highest-level, WWB's BeanForm component provides rich AJAX form functionality. The form is embedded in a Page designed by you. This allows you to create customized page designs and multiple BeanForms to be incorporated on a single page.Other lower-level components may be used independently of BeanForm (e.g., BeanGridPanel). BeanForm makes it very convenient to implement a bean-based form if you don't want to go to a lot of extra work. You focus on the model (beans), Fields within a form are dynamically sent back to the server-side bean as they are changed, which eliminates the typical form submit cycle. This makes WWB act more like a rich client application and less like a standard forms-based application.