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| Component _org.apache.wicket.markup.repeater.RefreshingView_ is a subclass of RepeatingView that comes with a customizable rendering strategy for its children components. |
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| RefreshingView defines abstract methods populateItem(Item) and getItemModels(). The first method is similar to the namesake method seen for ListView, but it takes in input an instance of class _org.apache.wicket.markup.repeater.Item_ which is a subclass of _ListItem_. RefreshingView is designed to display a collection of models containing the actual items. An iterator over these models is returned by the other abstract method getItemModels. |
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| The following code is a version of the previous example that uses _RefreshingView_ in place of _ListView_: |
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| *HTML:* |
| [source,html] |
| ---- |
| ... |
| <body> |
| <div id="bd" style="display: table;"> |
| <div wicket:id="persons" style="display: table-row;"> |
| <div style="display: table-cell;"><b>Full name: </b></div> |
| <div wicket:id="fullName" style="display: table-cell;"></div> |
| </div> |
| </div> |
| </body> |
| ... |
| ---- |
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| *Java Code (Page Constructor):* |
| [source,java] |
| ---- |
| public HomePage(final PageParameters parameters) { |
| //define the list of models to use |
| final List<IModel<Person>> persons = new ArrayList<IModel<Person>>(); |
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| persons.add(Model.of(new Person("John", "Smith"))); |
| persons.add(Model.of(new Person("Dan", "Wong"))); |
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| add(new RefreshingView<Person>("persons") { |
| @Override |
| protected void populateItem(Item<Person> item) { |
| item.add(new Label("fullName", new PropertyModel(item.getModel(), "fullName"))); |
| } |
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| @Override |
| protected Iterator<IModel<Person>> getItemModels() { |
| return persons.iterator(); |
| } |
| }); |
| } |
| ---- |
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| === Item reuse strategy |
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| Similar to _ListView_, the default behavior of the _RefreshingView_ is to replace its children with new instances every time is rendered. The strategy that decides if and how children components must be refreshed is returned by method _getItemReuseStrategy_. This strategy is an implementation of interface IItemReuseStrategy. The default implementation used by _RefreshingView_ is class _DefaultItemReuseStrategy_ but Wicket provides also strategy _ReuseIfModelsEqualStrategy_ which reuses an item if its model has been returned by the iterator obtained with method _getItemModels_. |
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| To set a custom strategy we must use method _setItemReuseStrategy_. |
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