Develop Reference

Error message displayed by FeedbackPanel does not clear on valid input submission in Wicket

I have a form where their is a dropdown and checkbox . When i dont provide any input i receive the error message set through the Feedback Panel as below code
private Form<ReportCriteria> createCriteriaPanel(String id, IModel<ReportCriteria> model) {
SelectionForm form = new SelectionForm(id, model);
ReportCriteria criteria = (ReportCriteria) getDefaultModelObject();
.......
FeedbackPanel fb = new FeedbackPanel("feedback");
fb.setOutputMarkupId(true);
form.add(fb);
DropDownChoice<Project> billableProjectsList = new DropDownChoice<>(
"projectsList",
......
new ChoiceRenderer<Project>("fullNameWithCustomer"));
form.add(billableProjectsList);
CheckGroup<Project> unbillablePrjct = .......
form.add(new FormComponentValidator(billableProjectsList, unbillablePrjct));
form.getFeedbackMessages().clear();
}
protected void onSubmit() {
SelectionForm.this.getFeedbackMessages().size());
TimesheetExportCriteriaPanel.this.SelectionForm.findForm("criteriaForm").getFeedbackMessages();
}
all the feedbackmessages value is empty and not retreieving anything .
I receive the error message from FormValidator correctly when i dont provide any inputs . When i provide the inputs and submit , the form refreshes and loads with the same error message .
I want it to clear when we provide valid input .
When checked on forums , i found for Wicket 6.x we need to use component.getFeedbackMessages() , but it is empty for me .
I am new to wicket .
Please help with the inputs .
public class FormComponentValidator extends AbstractFormValidator {
private static final long serialVersionUID = 1L;
private FormComponent<?>[] components;
#SuppressWarnings("unchecked")
public FormComponentValidator(FormComponent<?> selectedBillableProject, FormComponent<?> selectedUnBillableProject) {
components = new FormComponent[]{selectedBillableProject, selectedUnBillableProject};
}
/*
* (non-Javadoc)
* #see org.apache.wicket.markup.html.form.validation.IFormValidator#getDependentFormComponents()
*/
public FormComponent<?>[] getDependentFormComponents() {
return components;
}
/*
* (non-Javadoc)
* #see org.apache.wicket.markup.html.form.validation.IFormValidator#validate(org.apache.wicket.markup.html.form.Form)
*/
public void validate(Form<?> form ) {
if ((org.apache.commons.lang.StringUtils.isEmpty(components[0].getInput()) || components[0].getInput() == null )
&& (org.apache.commons.lang.StringUtils.isEmpty(components[1].getInput()) || components[1].getInput() == null)) {
error(components[0], "project.Required");
}
}
}
private void configureFeedback() {
// activate feedback panel
final FeedbackPanel feedbackPanel = new FeedbackPanel("feedback");
feedbackPanel.setOutputMarkupId(true);
feedbackPanel.setVisible(false);
add(feedbackPanel);
// don't show filtered feedback errors in feedback panel
final int[] filteredErrorLevels = new int[] { FeedbackMessage.ERROR };
feedbackPanel.setFilter(new IFeedbackMessageFilter() {
#Override
public boolean accept(FeedbackMessage message) {
for (int errorLevel : filteredErrorLevels) {
if (message.getLevel() == errorLevel) {
return false;
}
}
return true;
}

When submitting a Form Wicket runs all configured validators on all FormComponents (like TextInput, TextArea, DropDownChoice, etc.). If there is a validation error then a FeedbackMessage is associated with its respective FormComponent.
When rendering a FeedbackPanel Wicket visits all FormComponents and renders their FeedbackMessages (errors, infos, etc.).
At the end of the request cycle Wicket removes all rendered FeedbackMessages. If a FeedbackMessage is not rendered by any IFeedback component (like FeedbackPanel) then it will stay for the next request cycle.
This is done by DefaultCleanupFeedbackMessageFilter.
Put a breakpoint at DefaultCleanupFeedbackMessageFilter#accept() and see whether the problematic message is being accepted or not.

GXT-3 issue to load data for my Chart

My problem is annoying. My server side is generating 12 random numbers (double here).
My Client side received the correct data but nothing is displayed in my Chart. That worked fine with hardcoded data in the store but not with a REST call.
The transfer between my server and my client is that :
[{"key":"key0","value":0.47222548599297787},{"key":"key1","value":0.6009173797369691},{"key":"key2","value":0.13880104282435624},{"key":"key3","value":0.01804674319345545},{"key":"key4","value":0.5547733564202956},{"key":"key5","value":0.8229999661308851},{"key":"key6","value":0.8959346004391032},{"key":"key7","value":0.6848052288628435},{"key":"key8","value":0.10222856671111813},{"key":"key9","value":0.6931371931409103},{"key":"key10","value":0.2994297934549003},{"key":"key11","value":0.47566752196381334}]
Here my simple class used for my test. I am a newbie with GXT 3
public void onModuleLoad() {
final ListStore<JSOModel> store;
final ContentPanel panel = new FramedPanel();
RequestBuilder builder = new RequestBuilder(RequestBuilder.GET, "/ws/DocumentService/v1/test");
builder.setHeader("Accept", "application/json");
HttpProxy proxy = new HttpProxy(builder);
final Loader<ListLoadConfig, ListLoadResult<JSOModel>> loader = new ListLoader<ListLoadConfig, ListLoadResult<JSOModel>>(proxy, new DataReader<ListLoadResult<JSOModel>, String>() {
#Override
public ListLoadResult<JSOModel> read(Object loadConfig, String data) {
List<JSOModel> jsoModels = new ArrayList<JSOModel>();
JsArray<JSOModel> jsoModelJsArray = JSOModel.arrayFromJson(data);
if(jsoModelJsArray != null) {
for(int i = 0; i < jsoModelJsArray.length(); i++) {
jsoModels.add(jsoModelJsArray.get(i));
}
}
return new ListLoadResultBean<JSOModel>(jsoModels);
}
});
store = new ListStore<JSOModel>(new ModelKeyProvider<JSOModel>() {
#Override
public String getKey(JSOModel item) {
return item.get("key");
}
});
loader.addLoadHandler(new LoadResultListStoreBinding<ListLoadConfig, JSOModel, ListLoadResult<JSOModel>>(store) {
#Override
public void onLoad(LoadEvent<ListLoadConfig, ListLoadResult<JSOModel>> event) {
ListLoadResult<JSOModel> loaded = event.getLoadResult();
if(loaded.getData() == null) {
store.replaceAll(new ArrayList<JSOModel>());
} else {
store.replaceAll(loaded.getData());
}
}
});
Chart<JSOModel> chart = new Chart<JSOModel>();
chart.setStore(store);
chart.setShadowChart(true);
NumericAxis<JSOModel> axis = new NumericAxis<JSOModel>();
axis.setPosition(Chart.Position.LEFT);
axis.addField(new ValueProvider<JSOModel, Number>() {
#Override
public Number getValue(JSOModel JSOModel) {
return JSOModel.getNumber("value");
}
#Override
public void setValue(JSOModel JSOModel, Number number) {
}
#Override
public String getPath() {
return "key";
}
});
axis.setTitleConfig(new TextSprite("Number of hits"));
axis.setWidth(50);
axis.setMinimum(0);
axis.setMaximum(100);
chart.addAxis(axis);
PathSprite odd = new PathSprite();
odd.setOpacity(1);
odd.setFill(new Color("#dff"));
odd.setStroke(new Color("#aaa"));
odd.setStrokeWidth(0.5);
axis.setGridOddConfig(odd);
CategoryAxis<JSOModel, String> horizontalAxis = new CategoryAxis<JSOModel, String>();
horizontalAxis.setPosition(Chart.Position.BOTTOM);
horizontalAxis.setField(new ValueProvider<JSOModel, String>() {
#Override
public String getValue(JSOModel JSOModel) {
return JSOModel.get("key");
}
#Override
public void setValue(JSOModel JSOModel, String s) {
}
#Override
public String getPath() {
return "key";
}
});
horizontalAxis.setTitleConfig(new TextSprite("month of year"));
chart.addAxis(horizontalAxis);
LineSeries<JSOModel> column = new LineSeries<JSOModel>();
column.setYAxisPosition(Chart.Position.LEFT);
column.setStroke(new RGB(148,174,10));
column.setHighlighting(true);
chart.addSeries(column);
axis.addField(column.getYField());
chart.addSeries(column);
chart.setHeight(100);
chart.setWidth(100);
Button b = new Button("ha");
b.addClickHandler(new ClickHandler() {
#Override
public void onClick(ClickEvent clickEvent) {
loader.load();
}
});
RootPanel.get().add(b);
panel.setCollapsible(true);
panel.setHeadingText("Column Chart");
panel.setPixelSize(620, 500);
panel.setBodyBorder(true);
VerticalLayoutContainer layout = new VerticalLayoutContainer();
panel.add(layout);
chart.setLayoutData(new VerticalLayoutContainer.VerticalLayoutData(1,1));
layout.add(chart);
chart.setBackground(new Color("#dff"));
RootPanel.get().add(panel);

There are two ways to wire the chart into a store. One is to simply specify that the chart is using a store via setStore, as you have done:
chart.setStore(store);
When you do this, you must also inform the chart when it must redraw everything - you must call:
chart.redrawChart();
This call must be made shortly after the load is completed - consider doing it at the end of onLoad.
Why is this required? In some cases, developers want to make many changes to the store, one at a time, and if the chart automatically updated after each change, that would spawn many slow changes to the data model, and could end up looking strange. In a case like this, you would only call redrawChart() after all changes were complete.
There is another option however - instead of calling setStore, you can call bindStore, and ask the Chart to automatically update whenever any change occurs to the chart:
chart.bindStore(store);
In your case, this is likely the correct answer.

Disable back button in GWT

Is there a way to disable the Back button in a browser (basically clearing the History token stack) in GWT? Once I browse to a certain page in my application I want to make sure that the user can't use the back button to go back, but only be able to use links on the page to navigate the site.

You cannot disable a button just intercept it and change its return to something the browser does not understand.
This removes the history:
Window.addWindowClosingHandler(new ClosingHandler() {
#Override
public void onWindowClosing(ClosingEvent event) {
event.setMessage("My program");
}
});
To understand it see: http://groups.google.com/group/google-web-toolkit/browse_thread/thread/8b2a7ddad5a47af8/154ec7934eb6be42?lnk=gst&q=disable+back+button#154ec7934eb6be42
However, I would recommend not doing this because your it goes against good UI practices. Instead you should figure out a way that the back button does not cause a problem with your code.

Call the method below in the onModuleLoad().
private void setupHistory() {
final String initToken = History.getToken();
if (initToken.length() == 0) {
History.newItem("main");
}
// Add history listener
HandlerRegistration historyHandlerRegistration = History.addValueChangeHandler(new ValueChangeHandler() {
#Override
public void onValueChange(ValueChangeEvent event) {
String token = event.getValue();
if (initToken.equals(token)) {
History.newItem(initToken);
}
}
});
// Now that we've setup our listener, fire the initial history state.
History.fireCurrentHistoryState();
Window.addWindowClosingHandler(new ClosingHandler() {
boolean reloading = false;
#Override
public void onWindowClosing(ClosingEvent event) {
if (!reloading) {
String userAgent = Window.Navigator.getUserAgent();
if (userAgent.contains("MSIE")) {
if (!Window.confirm("Do you really want to exit?")) {
reloading = true;
Window.Location.reload(); // For IE
}
}
else {
event.setMessage("My App"); // For other browser
}
}
}
});
}

I found a way to make GWT ignore the back-button: Just add historyitem x if no historyitem was set and do nothing on x.
set a historyitem on startup
History.newItem("x")
in the ValueChangeHandler of History add the following:
String historyToken = event.getValue();
if (!historyToken.equals("x"))
History.newItem("x");

Window.addWindowClosingHandler(new ClosingHandler() {
#Override
public void onWindowClosing(ClosingEvent event) {
event.setMessage("My program");
}
});
That is not a fool proof solution. In fire fox I can press the back button and the onWindowClosing method is never invoked. The reason is that I have used History.newItem() and since history exists the back button or backspace buttons simply navigate through the browser history.
So....fix that :)

Put this in your index.html file:
window.open('html page(For example trial.html)', 'Name of the desired site', width='whatever you want',height='whatever you want', centerscreen=yes, menubar=no,toolbar=no,location=no,
personalbar=no, directories=no,status=no, resizable=yes, dependent=no, titlebar=no,dialog=no');

Hooking a GWT event onto an element in an external iframe

I am writing a GWT app that involves interacting with an external document in an iframe. As a proof of concept, I am trying to attach a click handler to a button.
The following works in javascript
var iframe = document.getElementById("rawJSIFrame");
var doc = iframe.contentDocument;
var body = doc.body;
var button = doc.getElementsByTagName("input").namedItem("submit");
button.onclick = function() {
alert("Clicked!");
};
Trying to do the equivalent in GWT, I did the following:
public void addClickHandlerToSubmitButton(String buttonElementName, ClickHandler clickHandler) {
IFrameElement iframe = IFrameElement.as(frame.getElement());
Document frameDocument = getIFrameDocument(iframe);
if (frameDocument != null) {
Element buttonElement = finder(frameDocument).tag("input").name(buttonElementName).findOne();
ElementWrapper wrapper = new ElementWrapper(buttonElement);
HandlerRegistration handlerRegistration = wrapper.addClickHandler(clickHandler);
}
}
private native Document getIFrameDocument(IFrameElement iframe)/*-{
return iframe.contentDocument;
}-*/;
The following is the ElementWrapper class:
public class ElementWrapper extends Widget implements HasClickHandlers {
public ElementWrapper(Element theElement) {
setElement(theElement);
}
public HandlerRegistration addClickHandler(ClickHandler handler) {
return addDomHandler(handler, ClickEvent.getType());
}
}
The code to find the button works fine but the actual click event handler is not getting invoked. Has anybody had a similar issue before, and how did you resolve it?
Thanks in advance,
Tin

Hilbrand is right about the problem being that the GWT method onAttach() was not called.
I implemented your original solution, adding the following method to ElementWrapper:
public void onAttach() {
super.onAttach();
}
And called added wrapper.onAttach() after the ElementWrapper is created. Works like a charm!

I expect the problem is that the GWT method onAttach() is not called when you use the wrapping as in your first example. You can try to use the static wrap method on the Button widget. Although to use this the input must be of type button. Or have a look at the implementation of the wrap method. Here is the modified code when using the wrap method:
Element buttonElement = finder(frameDocument).tag("input").name(buttonElementName).findOne();
Button button = Button.wrap(buttonElement);
HandlerRegistration handlerRegistration = button.addClickHandler(clickHandler);

After researching this further, I found that the iframe is irrelevant. The same behaviour doesn't work on a normal button on the host page.
I basically fixed it by using JSNI to replicate part of GWT's event handling mechanism. The following works:
Element buttonElement = DOM.getElementById("externalButton");
new CustomElementWrapper(buttonElement).addClickHandler(new ClickHandler() {
public void onClick(ClickEvent event) {
Window.alert("GWT hooked into button");
}
});
Where CustomElementWrapper is:
public class CustomElementWrapper extends Widget implements HasClickHandlers {
private ClickEventManager clickEventManager;
public CustomElementWrapper(Element theElement) {
setElement(theElement);
clickEventManager = new ClickEventManager(theElement);
}
public HandlerRegistration addClickHandler(ClickHandler handler) {
//The 'right' way of doing this would be the code below. However, this doesn't work
// A bug in GWT?
//
// return addDomHandler(handler, ClickEvent.getType());
return clickEventManager.registerClickHandler(handler);
}
void invokeClickHandler() {
clickEventManager.invokeClickHandler();
}
public boolean isClickHandlerRegistered() {
return clickEventManager.isClickHandlerRegistered();
}
}
Finally, the ClickEventManager, where the actual work happens is:
public class ClickEventManager {
private boolean clickHandlerRegistered = false;
private ClickHandler clickHandler;
private Element element;
public ClickEventManager(Element element) {
this.element = element;
}
public void invokeClickHandler() {
//This shouldn't really be null but we are bypassing GWT's native event mechanism
//so we can't create an event
clickHandler.onClick(null);
}
public boolean isClickHandlerRegistered() {
return clickHandlerRegistered;
}
HandlerRegistration registerClickHandler(ClickHandler handler) {
clickHandler = handler;
if (!clickHandlerRegistered) {
registerClickHandlerInJS(element);
clickHandlerRegistered = true;
}
return new HandlerRegistration() {
public void removeHandler() {
//For now, we don't support the removal of handlers
throw new UnsupportedOperationException();
}
};
}
private native void registerClickHandlerInJS(Element element)/*-{
element.__clickManager = this;
element.onclick
= function() {
var cm = this.__clickManager;
cm.#com.talktactics.agent2.client.widgets.ClickEventManager::invokeClickHandler()();
}
}-*/;
}
Personally, I hate this solution because I appear to be duplicating GWT's event handling and quite possibly introducing nasty javascript memory leaks. Any ideas on why my first post doesn't work (remembering that the iframe aspect is a red herring), would be appreciated.
Thanks,
Tin

You may find this helpful:
import com.google.gwt.dom.client.Element;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.event.dom.client.HasClickHandlers;
import com.google.gwt.event.shared.HandlerRegistration;
import com.google.gwt.user.client.ui.AbsolutePanel;
public class DirectPanel extends AbsolutePanel implements HasClickHandlers {
public DirectPanel(Element elem) {
super(elem.<com.google.gwt.user.client.Element> cast());
onAttach();
}
#Override
public HandlerRegistration addClickHandler(ClickHandler handler) {
return addDomHandler(handler, ClickEvent.getType());
}
}
You will then be able to make arbitrary containers into widget containers:
Element root = Document.get().getElementById("target");
DirectPanel p = new DirectPanel(root);
Button register = new Button("Register");
register.addClickHandler(new ClickHandler() {
#Override
public void onClick(ClickEvent event) {
// ...
}
});
p.add(register);
And bind events to arbitrary elements:
Element root = Document.get().getElementById("target");
DirectPanel p = new DirectPanel(root);
p.addClickHandler(new ClickHandler() {
#Override
public void onClick(ClickEvent event) {
// ...
}
});
Specifically in your case, try this:
IFrameElement frm = Document.get().createIFrameElement();
Document d = frm.getContentDocument();
NodeList<Element> inputs = d.getElementsByTagName("input");
InputElement target = null;
for(int i = 0; i < inputs.getLength(); ++i) {
Element e = inputs.getItem(0);
if (e.getNodeName().equals("submit")) {
target = InputElement.as(e);
break;
}
}
if (target != null) {
DirectPanel p = new DirectPanel(target);
p.addClickHandler(new ClickHandler() {
#Override
public void onClick(ClickEvent event) {
// TODO Auto-generated method stub
}
});
}
It's always mystified me that GWT makes doing this so difficult and poorly documented.

Instead of using iframes i suggest you simply make a http request from GWT via com.google.gwt.http.client.RequestBuilder. Like so:
private void getHtml(String url) {
RequestBuilder rb = new RequestBuilder(RequestBuilder.GET, url);
rb.setCallback(new RequestCallback() {
#Override
public void onResponseReceived(Request request, Response response) {
HTMLPanel html = new HTMLPanel(response.getText());
// Now you have a widget with the requested page
// thus you may do whatever you want with it.
}
#Override
public void onError(Request request, Throwable exception) {
Log.error("error " + exception);
}
});
try {
rb.send();
} catch (RequestException e) {
Log.error("error " + e);
}
}

You could use JSNI to reuse your JavaScript piece of code. Your javascript code would call a gwt method on an object that would throw it on behalf of the button in the iframe.
As to why GWT code does not work -- I guess that is because they use some layer on top of regular browser events that probably cannot span more than 1 frame. That's just a guess though. You could file this as a feature/bug request agains GWT team. If I am right your code looks just fine.

Please see my previous answer. A slight modification to your original solution will make it work.

Eclipse JFace's Wizards

I need a wizard which second page content depends on the first page's selection. The first page asks the user the "kind" of filter he wants to create and the second one asks the user to create one filter instance of the selected "kind".
JFace's wizards pages contents (createControl(...) method) are all created when the wizard is open and not when a given page is displayed (this allow JFace to know the wizard size I guess ??).
Because of this, I have to create my second page content BEFORE the wizard is opened BUT I can't since the second page's content depends on the first page selection.
For now the cleaner solution I found consists in creating all (seconds) pages before the wizard is open (with their content) and override the getNextPage() method in the first page's implementation.
The main drawback of that solution is that it can be be expensive when there are many second pages to create.
What do you think about that solution ? How do you manage your wizard's pages ? Is there any cleaner solution I missed ?

The approach is right if you are several other pages which are
completely different one with another
depends on the previous choices made in a previous page
Then you can add the next page dynamically (also as described here)
But if you have just a next page with a dynamic content, you should be able to create that content in the onEnterPage() method
public void createControl(Composite parent)
{
//
// create the composite to hold the widgets
//
this.composite = new Composite(parent, SWT.NONE);
//
// create the desired layout for this wizard page
//
GridLayout layout = new GridLayout();
layout.numColumns = 4;
this.composite.setLayout(layout);
// set the composite as the control for this page
setControl(this.composite);
}
void onEnterPage()
{
final MacroModel model = ((MacroWizard) getWizard()).model;
String selectedKey = model.selectedKey;
String[] attrs = (String[]) model.macroMap.get(selectedKey);
for (int i = 0; i < attrs.length; i++)
{
String attr = attrs[i];
Label label = new Label(this.composite, SWT.NONE);
label.setText(attr + ":");
new Text(this.composite, SWT.NONE);
}
pack();
}
As shown in the eclipse corner article Creating JFace Wizards:
We can change the order of the wizard pages by overwriting the getNextPage method of any wizard page.Before leaving the page, we save in the model the values chosen by the user. In our example, depending on the choice of travel the user will next see either the page with flights or the page for travelling by car.
public IWizardPage getNextPage(){
saveDataToModel();
if (planeButton.getSelection()) {
PlanePage page = ((HolidayWizard)getWizard()).planePage;
page.onEnterPage();
return page;
}
// Returns the next page depending on the selected button
if (carButton.getSelection()) {
return ((HolidayWizard)getWizard()).carPage;
}
return null;
}
We define a method to do this initialization for the PlanePage, onEnterPage() and we invoke this method when moving to the PlanePage, that is in the getNextPage() method for the first page.

If you want to start a new wizard based on your selection on the first page, you can use the JFace base class org.eclipse.jface.wizard.WizardSelectionPage.
The example below shows a list of available wizards defined by an extension point.
When you press Next, the selected wizard is started.
public class ModelSetupWizardSelectionPage extends WizardSelectionPage {
private ComboViewer providerViewer;
private IConfigurationElement selectedProvider;
public ModelSetupWizardSelectionPage(String pageName) {
super(pageName);
}
private class WizardNode implements IWizardNode {
private IWizard wizard = null;
private IConfigurationElement configurationElement;
public WizardNode(IConfigurationElement c) {
this.configurationElement = c;
}
#Override
public void dispose() {
}
#Override
public Point getExtent() {
return new Point(-1, -1);
}
#Override
public IWizard getWizard() {
if (wizard == null) {
try {
wizard = (IWizard) configurationElement
.createExecutableExtension("wizardClass");
} catch (CoreException e) {
}
}
return wizard;
}
#Override
public boolean isContentCreated() {
// TODO Auto-generated method stub
return wizard != null;
}
}
#Override
public void createControl(Composite parent) {
setTitle("Select model provider");
Composite main = new Composite(parent, SWT.NONE);
GridLayout gd = new GridLayout(2, false);
main.setLayout(gd);
new Label(main, SWT.NONE).setText("Model provider");
Combo providerList = new Combo(main, SWT.NONE);
providerViewer = new ComboViewer(providerList);
providerViewer.setLabelProvider(new LabelProvider() {
#Override
public String getText(Object element) {
if (element instanceof IConfigurationElement) {
IConfigurationElement c = (IConfigurationElement) element;
String result = c.getAttribute("name");
if (result == null || result.length() == 0) {
result = c.getAttribute("class");
}
return result;
}
return super.getText(element);
}
});
providerViewer
.addSelectionChangedListener(new ISelectionChangedListener() {
#Override
public void selectionChanged(SelectionChangedEvent event) {
ISelection selection = event.getSelection();
if (!selection.isEmpty()
&& selection instanceof IStructuredSelection) {
Object o = ((IStructuredSelection) selection)
.getFirstElement();
if (o instanceof IConfigurationElement) {
selectedProvider = (IConfigurationElement) o;
setMessage(selectedProvider.getAttribute("description"));
setSelectedNode(new WizardNode(selectedProvider));
}
}
}
});
providerViewer.setContentProvider(new ArrayContentProvider());
List<IConfigurationElement> providers = new ArrayList<IConfigurationElement>();
IExtensionRegistry registry = Platform.getExtensionRegistry();
IExtensionPoint extensionPoint = registry
.getExtensionPoint(<your extension point namespace>,<extension point name>);
if (extensionPoint != null) {
IExtension extensions[] = extensionPoint.getExtensions();
for (IExtension extension : extensions) {
IConfigurationElement configurationElements[] = extension
.getConfigurationElements();
for (IConfigurationElement c : configurationElements) {
providers.add(c);
}
}
}
providerViewer.setInput(providers);
setControl(main);
}
The corresponding wizard class looks like this:
public class ModelSetupWizard extends Wizard {
private ModelSetupWizardSelectionPage wizardSelectionPage;
public ModelSetupWizard() {
setForcePreviousAndNextButtons(true);
}
#Override
public boolean performFinish() {
// Do what you have to do to finish the wizard
return true;
}
#Override
public void addPages() {
wizardSelectionPage = new ModelSetupWizardSelectionPage("Select a wizard");
addPage(wizardSelectionPage);
}
}

Another alternative is to #Override setVisible. You can update page values or add additional widgets at that time.

I have a different solution.
If page depends on the result of page 1, create a variable and pass it into to first page, when that wizard page has the option from the user, then the last thing before the page is closed is to set the variable to the required value.
Then pass this variable to wizard, then pass it to the next wizard page. Then do a simple if statement and that way you get both choices together.
Remember that in most code there is only a small difference in the user options, so remember not to get bogged down in duplicating your code.