I have a rather complex form in the way that the number of form fields is flexibel. In short, the model object is a TLabel (TranslationLabel) that contains a Map of values (translations). Language here is an enum so the idea is that the number of fields (text areas) for which a translation is given depends on the values in this enum.
This is my form (simplified):
public class TranslationEditForm extends Form {
private final static List<Language> LANGUAGES = newArrayList(Language.values());
public TranslationEditForm(String id, final TranslationLabelView label) {
super(id, new CompoundPropertyModel<TranslationLabelView>(label));
ListView<Language> textAreas = new ListView<Language>("translationRepeater", LANGUAGES) {
#Override
protected void populateItem(final ListItem<Language> itemLang) {
//loop through the languages and create 1 textarea per language
itemLang.add(new Label("language", itemLang.getModelObject().toString()));
Model<String> textModel = new Model<String>() {
#Override
public String getObject() {
//return the value for current language
return label.getValue(itemLang.getModelObject());
}
#Override
public void setObject(String object) {
//set the value for current language
label.getTranslations().put(itemLang.getModelObject(), object);
}
};
itemLang.add(new TextArea<String>("value", textModel).setRequired(true));
}
};
//add the repeater containing a textarea per language to the form
this.add(textAreas);
}
}
Now, it works fine, 1 text area is created per language and its value is also set nicely; even more when changed the model gets updated as intended.
If you submit the form after emptying a text area (so originally there was a value) then of course there is a validation error (required). Normal (wicket) behaviour would be that the invalid field is still empty but for some reason the original value is reset and I don't understand why.
If I override onError like this:
#Override
protected void onError() {
this.updateFormComponentModels();
}
then it is fine, the value of the field is set to the submitted value (empty) instead of the original value.
Any idea what is causing this? What is wicket failing to do because the way I've set up the form (because with a simple form/model this is working fine as are the wicket examples)?
Posted as answer, so the question can be marked as solved:
ListView does recreate all its items at render time. This means that the validation will be broken. Have a look at API doc of the ListView
Calling setReuseItems() on the ListView solves this.
Regards,
Bert
Related
I would like to go through all fields in form data.
I know that in form I could do something like this :
// Go through all fields with IFormFieldVisitor
box.visitFields(new IFormFieldVisitor() {
#Override
public boolean visitField(IFormField field, int level, int fieldIndex) {
if (field instanceof MyClass) {
...
}
return true;
}
}, 0);
but form data doesn't have this options. How to do this in form data.
You can obtain them using
AbstractFormData.getFields to obtain the top-level fields. If you need nested fields as well, have a look at the more complex AbstractFormData.getAllFieldsRec().
AbstractFormData.getAllProperties to obtain properties that you have defined by annotating the getters and setters with #FormData
That was the simple case.
Now, if you are using the Scout Extension mechanism to add new elements to an existing form (and it's formdata), you will have to take those contributions into account.
If you need to do this, you can refer to the source code of the AbstractForm.importFormData to see how Scout implements this.
I want to create input forms which validate user input and prevent the model from being saved with invalid data. I have been using databinding which works up to a point but my implementation is not as intuitive as I would like.
Imagine an input which contains '123' and the value must not be empty. The user deletes the characters one by one until empty. The databinding validator shows an error decoration.
However, if the user saves the form and reloads it, then a '1' is displayed in the field - i.e. the last valid input. The databinding does not transmit the invalid value into the model.
I have a ChangeListener but this is called before the databinding so at that point the invalid state has not been detected.
I would like the error to be displayed in the UI but the model remains valid (this is already so). Also, for as long as the UI contains errors, it should not be possible to save the model.
/**
* Bind a text control to a property in the view model
**/
protected Binding bindText(DataBindingContext ctx, Control control,
Object viewModel, String property, IValidator validator)
{
IObservableValue value = WidgetProperties.text(SWT.Modify).observe(
control);
IObservableValue modelValue = BeanProperties.value(
viewModel.getClass(), property).observe(viewModel);
Binding binding = ctx.bindValue(value, modelValue, getStrategy(validator), null);
binding.getTarget().addChangeListener(listener);
ControlDecorationSupport.create(binding, SWT.TOP | SWT.LEFT);
return binding;
}
private UpdateValueStrategy getStrategy(IValidator validator)
{
if (validator == null)
return null;
UpdateValueStrategy strategy = new UpdateValueStrategy();
strategy.setBeforeSetValidator(validator);
return strategy;
}
private IChangeListener listener = new IChangeListener()
{
#Override
public void handleChange(ChangeEvent event)
{
// notify all form listeners that something has changed
}
};
/**
* Called by form owner to check if the form contains valid data e.g. before saving
**/
public boolean isValid()
{
System.out.println("isValid");
for (Object o : getDataContext().getValidationStatusProviders())
{
ValidationStatusProvider vsp = (ValidationStatusProvider) o;
IStatus status = (IStatus)vsp.getValidationStatus()
.getValue();
if (status.matches(IStatus.ERROR))
return false;
}
return true;
}
Your best bet is to steer clear of ChangeListeners - as you've discovered, their order of execution is either undefined or just not helpful in this case.
Instead, you want to stick with the 'observable' as opposed to 'listener' model for as long as possible. As already mentioned, create an AggregateValidationStatus to listen to the overall state of the DataBindingContext, which has a similar effect to your existing code.
Then you can either listen directly to that (as below) to affect the save ability, or you could even bind it to another bean.
IObservableValue statusValue = new AggregateValidationStatus(dbc, AggregateValidationStatus. MAX_SEVERITY);
statusValue.addListener(new IValueChangeListener() {
handleValueChange(ValueChangeEvent event) {
// change ability to save here...
}
});
You can use AggregateValidationStatus to observe the aggregate validation status:
IObservableValue value = new AggregateValidationStatus(bindContext.getBindings(),
AggregateValidationStatus.MAX_SEVERITY);
You can bind this to something which accepts an IStatus parameter and it will be called each time the validation status changes.
I am using a custom validator like as:
CustomValidator duplicateValidator;
duplicateValidator = new CustomValidator()
{
#Override
protected boolean condition(Object value)
{
getRecord();
//* .. code to validate this record here *//
}
};
But my page gets stuck in a loop, and by using Firebug, it stucks on getRecord(); part, also the getRecord() == null. Is there another way to get the record that I am editing ?
It could not stuck on getRecord method of CustomValidator because it's code is trivial - nothing could go wrong there:
/**
* #return field values for record being validated
*/
public Record getRecord() {
return record;
}
But depending on what you editing you can try to get edited record from that widget by using their specific methods.
For example for DynamicForm:
form.getValuesAsRecord()
For ListGrid:
listGrid.getEditedRecord(listGrid.getEditRow())
I have this code in my page constructor:
private String selectedAwsId;
private String selectedIsReal;
//these two are actually outside the constructor, and getters and setters for these two strings not shown
List<AwsCredentials> awsCredentials = (List<AwsCredentials>)getAwsCredentials();
List<String> awsIds = new ArrayList<String>();
for (AwsCredentials cred : awsCredentials){
awsIds.add(cred.getAwsId());
}
selectedAwsId = awsIds.get(0);
List<String> yesOrNo = Arrays.asList(new String[] { "sandbox", "real"});
selectedIsReal = "sandbox";
Form selectAwsCredentialsForm = new Form("selectAwsCredentialsForm"){
#Override
public void onSubmit() {
super.onSubmit();
//TODO: why isn't this updating the form?
}
};
add(selectAwsCredentialsForm);
selectAwsCredentialsForm.add(new DropDownChoice("selectAwsCredentialsDropdown", new PropertyModel(this, "selectedAwsId"), awsIds));
selectAwsCredentialsForm.add(new DropDownChoice("selectRealOrSandboxHitsDropdown", new PropertyModel(this, "selectedIsReal"), yesOrNo));
The first time I render the page, this works fine. But when I change the selection in either of the DropDownChoices and submit the form, the page doesn't change (values in the selectedAwsId and selectedIsReal aren't altered accordingly). Is there something I'm missing in my understanding of how forms work? Does the entire page get refreshed when a form gets submitted (does the constructor get run again?)
You might want to construct a model and set this as your form's model. (This is what I do.) Submitting the form (and if all is coded appropriately) will then result in the form's model being updated.
Does anyone know for an example of GWT's CellTable using RequestFactory and that table is being edited? I would like to list objects in a table (each row is one object and each column is one property), be able to easily add new objects and edit. I know for Google's DynaTableRf example, but that one doesn't edit.
I searched Google and stackoverflow but wasn't able to find one. I got a bit confused with RF's context and than people also mentioned some "driver".
To demonstrate where I currently arrived, I attach code for one column:
// Create name column.
Column<PersonProxy, String> nameColumn = new Column<PersonProxy, String>(
new EditTextCell()) {
#Override
public String getValue(PersonProxy person) {
String ret = person.getName();
return ret != null ? ret : "";
}
};
nameColumn.setFieldUpdater(new FieldUpdater<PersonProxy, String>() {
#Override
public void update(int index, PersonProxy object, String value) {
PersonRequest req = FaceOrgFactory.getInstance().requestFactory().personRequest();
PersonProxy eObject = req.edit(object);
eObject.setName(value);
req.persist().using(eObject).fire();
}
});
and my code for data provider:
AsyncDataProvider<PersonProxy> personDataProvider = new AsyncDataProvider<PersonProxy>() {
#Override
protected void onRangeChanged(HasData<PersonProxy> display) {
final Range range = display.getVisibleRange();
fetch(range.getStart());
}
};
personDataProvider.addDataDisplay(personTable);
...
private void fetch(final int start) {
lastFetch = start;
requestFactory.personRequest().getPeople(start, numRows).fire(new Receiver<List<PersonProxy>>() {
#Override
public void onSuccess(List<PersonProxy> response) {
if (lastFetch != start){
return;
}
int responses = response.size();
if (start >= (personTable.getRowCount()-numRows)){
PersonProxy newP = requestFactory.personRequest().create(PersonProxy.class);
response.add(newP);
responses++;
}
personTable.setRowData(start, response);
personPager.setPageStart(start);
}
});
requestFactory.personRequest().countPersons().fire(new Receiver<Integer>() {
#Override
public void onSuccess(Integer response) {
personTable.setRowCount(response+1, true);
}
});
}
I try to insert last object a new empty object. And when user would fill it, I'd insert new one after it. But the code is not working. I says that user is "attempting" to edit a object previously edited by another RequestContext.
Dilemmas:
* am I creating too many context'es?
* how to properly insert new object into celltable, created on the client side?
* on fieldUpdater when I get an editable object - should I insert it back to table or forget about it?
Thanks for any help.
am I creating too many context'es?
Yes.
You should have one context per HTTP request (per fire()), and a context that is not fire()d is useless (only do that if you/the user change your/his mind and don't want to, e.g., save your/his changes).
You actually have only one context to remove here (see below).
Note that your approach of saving on each field change can lead to "race conditions", because a proxy can be edit()ed by at most one context at a time, and it remains attached to a context until the server responds (and once a context is fired, the proxy is frozen –read-only– also until the server responds).
(this is not true in all cases: when onConstraintViolation is called, the context and its proxies are unfrozen so you can "fix" the constraint violations and fire the context again; this should be safe because validation is done on the server-side before any service method is called).
how to properly insert new object into celltable, created on the client side?
Your code looks OK, except that you should create your proxy in the same context as the one you'll use to persist it.
on fieldUpdater when I get an editable object - should I insert it back to table or forget about it?
I'm not 100% certain but I think you should refresh the table (something like setRowData(index, Collections.singletonList(object)))
BTW, the driver people mention is probably the RequestFactoryEditorDriver from the Editor framework. It won't help you here (quite the contrary actually).