I have a table in my jsf application with some data from the database. I have made the id values a link, and my goal is to pass the data from the selected row to another facelet. How can I do this? The href I have is:
<td>#{product.id}</td>
So the goal is that when the user clicks the link, the editOrDeletePage is displayed, and I want the editOrDeletePage to "ingest" the product id, so that it knows what data to display? How can I do this?
If you definetely want to use static links, you may, of course, just read a request parameter from a target page using some kind of event listener
<f:event listener="#{bean.preRender}" type="preRenderView" />
And read the parameter from request:
FacesContext facesContext = FacesContext.getCurrentInstance();
String productId = (String) facesContext.getExternalContext().
getRequestParameterMap().get("productid");
But it's not really a JSF way to handle navigation, I belive. You may want to use commandLink or some other way of handling user actions. Or maybe, even better, think of using data table, where a user can choose a row, and you can process selection.
Related
I have a browse.xhtml where I browse a list of cars and I want to view the details of the car in details.xhtml when a "View more" button is pressed. Their backing beans are #ViewScoped and are called BrowseBean and DetailsBean, respectively.
Now, I wouldn't like the user/client to see the car ID in the URL, so I would like to avoid using GET params, as presented here and here.
Is there any way to achieve this? I'm using Mojarra 2.2.8 with PrimeFaces 5 and OmniFaces 1.8.1.
Depends on whether you're sending a redirect or merely navigating.
If you're sending a redirect, then put it in the flash scope:
Faces.setFlashAttribute("car", car);
This is available in the #PostConstruct of the next bean as:
Car car = Faces.getFlashAttribute("car");
Or, if you're merely navigating, then put it in the request scope:
Faces.setRequestAttribute("car", car);
This is available in the #PostConstruct of the next bean as:
Car car = Faces.getRequestAttribute("car");
See also:
Injecting one view scoped bean in another view scoped bean causes it to be recreated
How to pass objects from one page to another page in JSF without writing a converter
Note that I assume that you're very well aware about the design choice of having two entirely separate views which cannot exist (be idempotent) without the other view, instead of having e.g. a single view with conditionally rendered content. And that you already know how exactly the view should behave when it's actually being requested idempotently (i.e. via a bookmark, shared link, by a searchbot, etc). If not, then I strongly recommend to carefully read the answer on this question: How to navigate in JSF? How to make URL reflect current page (and not previous one).
Update: in case you're not using OmniFaces, use respectively the following:
FacesContext.getCurrentInstance().getExternalContext().getFlash().put("car", car);
Car car = (Car) FacesContext.getCurrentInstance().getExternalContext().getFlash().get("car");
FacesContext.getCurrentInstance().getExternalContext().getRequestMap().put("car", car);
Car car = (Car) FacesContext.getCurrentInstance().getExternalContext().getRequestMap().get("car");
This has to be a dumb question, but I can't seem to find the right keywords to google on: I have an action listener that can receive an event from any one of multiple checkboxes that were all generated from the same line of jsp in a dataTable. How can I tell from the action listener which one issued the event?
In particular, I need the index of the component so I can map it to an ordered list in the model. I know I can get the UIComponent object, and from there I can get the client ID of the component. And knowing that the client ID has the component's index embedded in it, yes I could do the sleazy thing, and parse the index from the client ID. But I know that would be a horrible, fragile and unmaintainable hack.
What's the right way to do this?
After an initial search, I think this could help you.
http://illegalargumentexception.blogspot.com/2009/02/jsf-working-with-component-ids.html
Have you tried to use f:param in addition to the checkbox values to pass custom parameters, so that would be more cleaner than working with ID's to manipulate business logic. ID.
Using the DataTables var attribute, you should be able to do this
<h:dataTable ... var="currentRow">
....
<h:selectBooleanCheckbox ... actionListener="#{blah.doThis}">
<f:attribute name="curRec" value="#{currentRow}" />
</h:selectBooleanCheckbox>
bean:
public void doThis(ActionEvent ae)
{
TreeMap myMap = (TreeMap)ae.getComponent().getAttributes().get("curRec");
...
}
Edit: The binding variable of your datatable should have the method getRowIndex();. That should give you the index of the record that caused the event in the table. I'm referencing an ICEfaces project, so I apologize if that isn't correct. Let me know, thx.
I am trying to implement an audit trail functionality for my web application that records:
lastModified (timestamp)
modifiedBy (user information)
userComment (reason for value change)
for each of my input fields (input fields are spread over several forms with different backing beans and different valueHolder classes).
The first two (lastModified and modifiedBy) are easily done with the help of an JPA AuditListener and #PrePersit and #PreUpdate methods.
The third one is a bit tricky since it requires user interaction. Best would be a dialog that asks for the user comment.
So there are (at least) two open issues: Can I establish a "global" valueChangeListener for all input fields in my application? Is this possible without attaching <f:valueChangeListener> to each single input component? Second: How can I grab the user comment. My idea is to put a p:dialog in my web page template but this dialog needs to know from which input component it is called.
Can I establish a "global" valueChangeListener for all input fields in my application? Is this possible without attaching to each single input component?
Yes, with a SystemEventListener which get executed during PreRenderViewEvent. You need to walk through the component tree as obtained by FacesContext#getViewRoot() to find all components which are an instanceofEditableValueHolder (or something more finer-grained) and then add the new YourValueChangeListener() by the addValueChangeListener() method. See also this answer how to register the system event listener: How to apply a JSF2 phaselistener after viewroot gets built?
Second: How can I grab the user comment. My idea is to put a p:dialog in my web page template but this dialog needs to know from which input component it is called.
You could in YourValueChangeListener#processValueChange() set the component in question as a property of some request or view scoped which you grab by evaluateExpressionGet().
Recorder recorder = (Recorder) context.getApplication().evaluateExpressionGet(context, "#{recorder}", Recorder.class);
recorder.setComponent(event.getComponent());
// ...
It will execute the EL and auto-create the bean in its scope if necessary. The bean in turn should also hold the property representing the user comment. Finally, you can use it in your <p:dialog>.
<p>You have edited #{recorder.component.label}, please mention the reason:</p>
...
<h:inputText value="#{recorder.comment}" />
I have a situation, I have a session bean with list, this list I show in html data table. When the user hits the url from browser or normal href, I have to show all records. There is provision to search for the data also, where I have to show the filtered list. Now after a user has made the search, the list contains filtered records and after doing this he leaves the page to some other, and now if the user hits the url or uses the menu to come back to this page, since I have this list in session bean, I still have the filtered list.
Since there is no default action in JSF 1.1 or 2.0 preRenderView concept, its difficult to clear the list and get non filtered data(all results) again. Even tricks in getList() method fail to accomplish the task.
I have planned to use phase listener, as when a user reaches a page via href or url hit in browser, invoke application phase does not happen. I can toggle boolean variable in my session bean and in getList() I can perform some trick to check it was url,href hit or by command button.
Hope I have made myself clear. In short I have to identify in my bean whether the request came directly from href,browser or an action. If search action filter records for data table if not keep list cache and keep showing it as long as search is not made.
Just guide me whether I am doing things in right way or thinking too much or can it be done in much more efficient way.
Thanks in advance.
Well platform is jsf 1.1 in weblogic portal 10.3 .....
JSF 1.x actions use by default POST method. Direct links/bookmarks/etc are by nature GET method. Since there's no ResponseStateManager#isPostback() or FacesContext#isPostback() in JSF 1.1, you have to determine the request method yourself:
HttpServletRequest request = (HttpServletRequest) facesContext.getExternalContext().getRequest();
boolean postback = "POST".equalsIgnoreCase(request.getMethod());
Or check for a certain parameter in the request parameter map, but I can't tell from top of head which one you'd like to check. You've to determine it yourself.
boolean postback = facesContext.getExternalContext().getRequestParameterMap().containsKey(SOME_KEY);
If postback is true, then a JSF action is been invoked.
If I have many input controls in a form (There are separate validators for each of these input controls - like required,length and so on ) , there is a command button which submits the form and calls an action method. The requirement is - though the input control values are , say , individually okay - the combination of these values should be okay to process them together after the form submission - Where do i place the code to validate them together?
1) Can i add a custom validator for the command button and validate the combination together? like validate(FacesContext arg0, UIComponent arg1, Object value) but even then I will not have values of the other input controls except for the command button's/component's value right ?
2) can i do the validation of the combination in the action method and add validation messages using FacesMessage ?
or do you suggest any other approach?
Thanks for your time.
Point 2 is already answered by Bozho. Just use FacesContext#addMessage(). A null client ID will let it land in <h:messages globalOnly="true">. A fixed client ID like formId:inputId will let it land in <h:message for="inputId">.
Point 1 is doable, you can grab the other components inside the validator method using UIViewRoot#findComponent():
UIInput otherInput = (UIInput) context.getViewRoot().findComponent("formId:otherInputId");
String value = (String) otherInput.getValue();
You however need to place f:validator in the last UIInput component. Placing it in an UICommand component (like the button) won't work.
True, hardcoding the client ID's is nasty, but that's the payoff of a bit inflexible validation mechanism in JSF.
I've just landed on your post after having the same question.
Articles I have read so far identify that there are four types of validation for the following purposes:
Built into the Components (subscribe to individual fields; required=true, LengthValidator, etc)
'Application Validation' added to the Action in the Backing Bean (Business Logic)
Custom Validators (subscribe to individual fields)
Method in the Backing Bean used as a Custom Validator (subscribe to individual fields).
With reference to Validators: The validation mechanism in JSF was designed to validate a single component. (See S/O Question here)
In the case where you want to validate a whole form as a logical grouping of fields, it appears with standard JSF/Apache MyFaces that the most appropriate to do it is as Application Validation, as the set of individual fields take on a collective business meaning at this point.
BalusC has come up with a way of shoehorning form validation into a single validator attached to the last form item (again, see S/O Question here and another worked example on his website here) however it isn't necessarily extensible/reusable, as the references to the ID's of the form have to be hardcoded as you can't append to the validate() method's signature. You'll get away with it if you're only using the form once, but if it pops up a few times or if you generate your ID's programmatically, you're stuck.
The JSF implementation portion of Seam has a <s:validateForm /> control which can take the IDs of fields elsewhere in your form as parameters. Unfortunately, it doesn't appear that any of the MyFaces/Mojara/Sun JSF implementations have an equivalent as it isn't part of the standard.
I've successfully used the 2nd approach:
FacesMessage facesMessage =
new FacesMessage(FacesMessage.SEVERITY_ERROR, msg, msg);
FacesContext.getCurrentInstance().addMessage(null, facesMessage);