| Note |
|---|
| title | target.addComponent(myComponent) |
|---|
|
Be careful that when target.addComponent(myComponent) that myComponent.setOutputMarkupId(true) has been set. The ID is required in order for an update can be made on the client. |
Adding Views To Targets
You may be tempted to add a view (ListView, RefreshingView, DataView, etc.) to an AjaxRequestTarget only to to find out that you receive an exception indicating that the view cannot be added to the target. Here are a few tips when adding an updated views to targets:
- Do not add the view to a target. Use a parent component instead.
- If the view is within a Panel do not add the panel to the target. Use a WebMarkupContainer (or similar component) instead.
Below is an example of a view using a WebMarkupContainer to target a RefreshingView. When a WebPage using the panel calls the addRatingScaleComponents(final AjaxRequestTarget target) method the ratingScaleContainer will be added to the target (not the panel):
| Code Block |
|---|
| title | AbstractRatingScalePanel.java |
|---|
|
public abstract class AbstractRatingScalePanel extends Panel {
private final WebMarkupContainer ratingScaleContainer;
private final RefreshingView ratingScalesView;
/**
* Creates a rating scale creation/display panel
*
* @param id
* the ID of the panel
* @param headerLabelModel
* the model that will be used for the header
*/
public AbstractRatingScalePanel(final String id, final IModel headerLabelModel) {
super(id);
add(new Label("legend-scale-header", headerLabelModel));
ratingScaleContainer = new WebMarkupContainer("div-rating-scale-container");
// add the initial list of rating scales
ratingScalesView = new RefreshingView("tr-rating-scale") {
private static final long serialVersionUID = 1L;
/**
* {@inheritDoc}
*/
@Override
protected final void populateItem(final Item item) {// WicketAjaxIndicatorAppender IndicatingAjaxLink
// add the rating scale components
item.add(new TextField("boundary"));
item.add(new Label("rating"));
}
/**
* {@inheritDoc}
*/
@SuppressWarnings("unchecked")
@Override
protected Iterator<RatingScale> getItemModels() {
// load the rating scales
return new ModelIteratorAdapter(loadRatingScales().iterator()) {
/**
* {@inheritDoc}
*/
@Override
protected final IModel model(final Object object) {
return new CompoundPropertyModel((RatingScale) object);
}
};
}
};
// surround the view with a markup container
ratingScaleContainer.add(ratingScalesView);
add(ratingScaleContainer.setOutputMarkupId(true));
}
/**
* Adds the rating scale component(s) to the specified target
*
* @param target
* the target to add the component(s) to
*/
public final void addRatingScaleComponents(final AjaxRequestTarget target) {
target.addComponent(ratingScaleContainer);
}
/**
* Loads/returns the rating scales used by the panel
*
* @return the rating scales used by the panel
*/
protected abstract List<RatingScale> loadRatingScales();
}
|
| Code Block |
|---|
| title | AbstractRatingScalePanel.html |
|---|
|
<?xml version="1.0" encoding="UTF-8"?>
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:wicket="http://wicket.apache.org"
xsi:schemaLocation="http://www.w3.org/MarkUp/SCHEMA/xhtml11.xsd http://wicket.apache.org"
xml:lang="en">
<body>
<wicket:panel>
<fieldset>
<legend wicket:id="legend-scale-header">
[4. Determine On What Scale You Will Be Scored]
</legend>
<div wicket:id="div-rating-scale-container">
<table border="0">
<tr wicket:id="tr-rating-scale">
<td style="text-align:center;">
<input wicket:id="boundary" type="text" size="10" />
</td>
<td>
=
</td>
<td>
<span wicket:id="rating">
[Rating Value]
</span>
</td>
</tr>
</table>
</div>
</fieldset>
</wicket:panel>
</body>
</html>
|