Is there any easier way to set to process only those input fields within a h:form whose values have actually been changed at the client side ignoring those that havent changed?
Using JSF 2.2 with
Primefaces 3.2
Not in JSF 2.2, nor in PrimeFaces 3.2.
Closest what you can get is PrimeFaces 3.3 (currently only available as snapshot) with new client ID selector syntax which is borrowed from the jQuery selector API. Unfortunately, this doesn't support some :changed selector (even already not in jQuery selector API).
This is not exactly trivial to implement and integrate in PrimeFaces JS API. You basically need to hook a change listener on every single input element in the background wherein you collect client IDs of those who have been changed.
Related
In this beginner's JSF tuorial
section 1.1 says:
JSF UI components and their state are represented on the server with a defined life-cycle of the UI components.
But in the example that follows, I am unable to see how the state of an UI component is managed by the server? The example looks like a standard servlet jsp example minus the servlet mappings.
My other question is that in the example, we are accessing the jsp directly. Is this the standard thing to do in JSF as opposed to using servlet mappings?
First of all, if you're a beginner, I encourage you not to look at that old tutorials and find a good JSF 2.x one. JSF 2 was released in 2009 and you should consider it as the branch to learn, as it brings several advantages comparing with 1.x old versions.
JSF has its own lifecycle for any request you make from the browser which can be a GET or POST request, even an ajax based one. What you basically have to understand about JSF comparing with other frameworks is that it's stateful. In other words, you can keep a component's state from one request to another (you actually have a view state, which can be kept no matter how many requests you do, until you change the view).
Appart from that, about your last statement, in old JSF ages the servlet mapping used to be done over .*jsf suffix. It means, when you make a request for that in the browser, jsf will convert the matching jsp page and display it.
JSF 2 however introduced facelets, which are based in .xhtml view pages. It's now also possible to do the mapping as .xhtml having the source code in an .xhtml too and JSF will make the conversion. The main advantage for this is that end user will not be allowed to see the sources, as browser's request matches source page's url, so JSF servlet will always be invoked.
I am using Apache MyFaces lib to create JSF Tags, for example HtmlAjaxCommandLink. There is a method setReRender(parameter) to identify the corresponding element, which should get updated. In my HTML-source the corresponding anchor has an id-attribute with the value 'subformContainer_7_facesMessagesContainer'.
What do I have to set as a parameter? Thanks in advance.
Currently the area (a t:div) is not rerendered at all. To evaluate if the area is rerendered I am using a randomNumberString, so I should recognize if the value changes.
String rrString = "subformContainer_7_facesMessagesContainer";System.out.println("DEBUG rrString : " + rrString);
treeResizeButton.setReRender(rrString);
If you want to tell JSF to re-render a component in the current Ajax request, you can use the API for PartialViewContext:
PartialViewContext partialViewCtx = FacesContext.getInstance().getPartialViewContext();
partialViewCtx.getRenderIds().add("putYourClientIdHere")
Or, if you use the OmniFaces library, you can simply use Ajax#update.
I am trying to get the reusable group of jsf 1.2 components inside a panelgrid using Facelet tag file. #Balusc's previous answer at How to make a grid of JSF composite component? was a fabulous resource. I have a couple of followup questions:
In my c:when how do I test for the tagName itself instead of checking for the attributes. Instead of
<c:when test="#{type != 'submit'}">
I want to check tagName itself to decide how to format it. If 'input' do xxx.
2 Is this approach is still valid with jsf 1.2 other than f:ajax? If yes, can I replace with a4j:support...?
In my c:when how do I test for the tagName itself instead of checking for the attributes.
I'm not sure how this question makes sense. It sounds like that you're approaching something not entirely right. Do you maybe have copypasted exactly the same piece of code over multiple tag files? You should not do that. Make it a reuseable <ui:composition> or maybe <ui:decoration> instead which you compose/decorate in every tag file along with a fixed and unique <ui:param> value depending on the taglib file.
Is this approach is still valid with jsf 1.2 other than f:ajax? If yes, can I replace with a4j:support...?
Being able to create tag files is not necessarily specific to JSF, but to the view technology used, which is in this case Facelets. You can even do similar stuff in its predecesor JSP, see also this answer for an example: JSF 1.2 custom component from jsp:include It should work just fine in every JSF version supporting the view technology in question.
As to ajax support, it doesn't matter to the tag file what you're all doing inside the tag file. If you want and can use <a4j:support> then just do it.
I'm developing an application in JSF 2.0.
I was wondering if there is a JSF component that supports an autocomplete function and that can hold multiple values (that binds to an array or a list). I don't have the time and knowledge to create such a component myself.
I know PrimeFaces has got the p:autoComplete (http://www.primefaces.org/showcase-labs/ui/autoCompletePojo.jsf) component, but it can only 'hold' one value. I'd need a component that can do what p:auotoComplete does, but multiple times; the textarea should be able to display multiple values. Is there a library that contains such a component?
Any help would be greatly appreciated.
The latest PrimeFaces snapshot 3.1 got AutoComplete - Multiple Selection
You can get it from here
3.1-SNAPSHOT
You might see this Richfaces example. I think that tokens and autoFill = "false" will work.
I have a widget in my application that I need to display at two places(once in main page body and once through dialog box). Currently its code has been added twice in the page. Now I was thinking, If there was a way I could just include it only once and show the same instance in the dialog box, as in the main page body.
Can you suggest a way for this?
I'm Using:-
JSF 2.0 with Facelets
Primefaces 3.0 M3 Snapshot
JSF 2 has exactly the feature you want: it's called composite components. I bascially allows you to write a bunch of Facelet code into a file and use it just like any other JSF component, pass parameters to it, etc.