I have a commandLink that do a POST, and the action listener in the bean fill the request map with a new parameter like this
FacesContext.getCurrentInstance().getExternalContext().getRequestMap().put("confirmationWindowMessage","test");
In the view if I make #{param['confirmationWindowMessage']} nothing is presented. Why is this happening?
The action listener does not redirect to another view, so the view is the same.
You can't and shouldn't fill the #{param} object. This is a client-controlled map. Moreover, any attempt should go through getRequestParameterMap(), not getRequestMap(). The getRequestMap() represents the request attribtues, not request parameters.
Request attributes are just available by #{attributeName}. Thus, in your particular case so:
<p>#{confirmationWindowMessage}</p>
An alternative is to just make it a property of a request scoped bean. Or perhaps even better, a faces message.
Related
I am trying to make my app "Bookmarkable", and i am using view parameters to achieve it.
And i think i still do not get the right way to do it right in JSF, even after reading this, and many others.
My problem is that the get parameters get lost after any non-ajax postback, i mean, the parameter value is still set in the bean and the app works correctly, but it gets removed from the URL making the URL invalid.
For instance, having an URL like http://company.com/users?id=4, as soon as that page executes a non-ajax postback (for uploading data, for instance) the URL becomes just http://company.com/users. The app continues to work correctly, but the link is not any more "Bookmarkable".
Is there any way to prevent the non-ajax postbacks removing the viewParams from the URL?
My use case is to be able to bookmark a page to EDIT an object, and there i need to be able to upload data (if not i would not use non-ajax postbacks). I know i would not need any postback if i would want to bookmark the page to only VIEW the data of the object, but that is not my case.
I could also do a redirect to the same page with the same params, and let the app to recreate the view scoped bean, but then i really do not see any benefit over request scoped beans...
Any suggestion is very appreciated.
This behaviour is "by design". The <h:form> generates a HTML <form> element with an action URL without any view parameters. The synchronous POST request just submits to exactly that URL which thus get reflected as-is in browser's address bar. If you intend to keep the view parameters in the URL, while using ajax is not an option, then you basically need to create a custom ViewHandler which has the getActionURL() overridden to include the view parameters. This method is used by <h:form> to generate the action URL.
public String getActionURL(FacesContext context, String viewId) {
String originalActionURL = super.getActionURL(context, viewId);
String newActionURL = includeViewParamsIfNecessary(context, originalActionURL);
return newActionURL;
}
Or, as you're based on the comments already using OmniFaces, you could also use its <o:form> component which basically extends the <h:form> with the includeViewParams attribute which works much like the same as in <h:link> and <h:button>.
<o:form includeViewParams="true">
...
</o:form>
This way all <f:viewParam> values will end up in the form action URL.
See also:
Handling view parameters in JSF after post
This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
How to choose the right bean scope?
I'm newbie in JSF programming, and I need a clarification about bean scopes. I have already read all the questions about this argument, but is not so clear.
I don't understand the request scope well. I understand that: "This is the default scope and basically the bean is alive throughout a single HTTP request."
So for example, suppose that we ask the browser to open a web page with a form. When we make the request, a request scope bean is created, the life-cycle begins and after the render response phase, the Java bean is destroyed.
Then we fill out the form and we press a button. This will start another HTTP request, right?
In the same context, if a have a view scope bean instead of a request scope bean, what is the difference? How many bean instances are created? Why is it better to use this with a datatable?
The request scope as all your sources including the post linked by BalusC say starts living a short while after your request hits the server, and is destroyed shortly after the last bit of the response has been send back.
Indeed, if you postback a form a new request starts and thus a new request scope. This means everything that is request scoped will be created again. So for a form that is first rendered, and then posted back once, 2 request scoped beans will be created.
The view scope lives as long as you do postbacks to the same view (page). This works by means of the hidden form parameter called javax.faces.ViewState. The value of this is an entry into some kind of logical Map if you use save state on server. How a JSF implementation actually resolves this is not that important here (but yes, it's mostly just a Map).
After the postback JSF is able to retrieve the exact same view scoped beans again by means of this parameter. So for a form that is first rendered, and then posted back once, 1 view scoped bean will be created.
For a datatable you will almost always want to use the view scope. The reason is that you want the data to be the same before and after a postback. If your data is 100% static and/or you don't have postbacks (your table is not in a form), you can use the request scope instead.
Does anyone have a solution for such a problem:
In my app I'm using a complex, programmatically build dashboard based on the primefaces dashboard. To overcome problems with nonunique id's of the panels building the dashboard, I'm binding this component to a request-scoped bean. I'd also like to rebuild the dashboard based on some changable parameters after clicking a commandButton.
The problem is, that the getter for the dashboard is fired in the Apply Request Values phase, way before the actionListener of the commandButton is fired (in the Invoke Application phase). So, although the dashboard is rebuild eventually, it's not beeing refreshed in the rendered response.
On the other hand, if I try to set immediate attribute of the button to true, the actionListener is fired in the Apply Request Values phase, but still after the getter. Than the lifecycle goes directly to the Render Response phase, and the outcome is the same.
Anyone?
Thank you for the answer. Let me add a bit detail to my problem.
I store a model of a sports tournament as a property of a session scoped bean. It goes like this: the bean has a property "tournament". This class has a list of groups, each with it's table of matches. The idea was to use three different programmatically built components as renderers of this tournament model.
The dashboard would be used for drag-and-drop edition of contestant placement in groups. For viewing match tables and editing their matches I use a tab panel, with panel grid for every table. Finally, I use a panel grid to show a tournament tree. Every of those three components render some part of the model for the user to edit.
Since the model (and therefore those rendering components) are dynamically build depanding on chosable parameters like number of groups for example, i had a problem with id uniqnes when binding them to a session-scoped bean. So I bound them to a request scoped bean. With every request changing the model (mostly ajax) I wanted to rerender those components depending on the parameters set by the user (also stored in the session scoped bean).
The problem is, that when I rebuild the model in the invoke application phase (in a action listener fired by the "rebuild-my-model" button), the components bound to a request-scoped bean have already been "get-ed" from the bean (or so it seems), and they do not refresh on the page.
I would be very gratefull for a clue to what i'm doing wrong, and perhaps a suggestion, if the approach mentioned above is completelly stupid :)
The problem is, that the getter for the dashboard is fired in the Apply Request Values phase, way before the actionListener of the commandButton is fired
I'm not sure why exactly that forms a problem for you. Perhaps you're incorrectly doing business logic in the getter method instead of in the action listener method? Or perhaps you're manually creating the component instead of referencing the JSF-created one and thus always overridding the one in the JSF view?
A proper JSF getter method basically look like this:
public UIComponent getDashboard() {
return dashboard;
}
It should not contain any other line of code. The same applies to the setter method by the way. Any actions wherein you need to manipulate the component's children needs to be done in an action(listener) method, not in a getter/setter method.
I wrote two pages...one a form where data submitted and second just to confirm the transaction actually carried out some calculation.
I have a managed bean i.e. FormDataBean and a class Reservation.java from which i instantiate for each booking made. Now I have at the end of a form a submit button:
<h:commandButton value="Submit" action="confirmation"/>
in the bean I have setters and getters as usual. in a method i defined I create an instance of Reservation, then set the beans variables to the instance variabels, like
reservation.startDate = startDate;
reservation.endDate = endDate;
reservation.checkRange();
The last method, i.e. checkRange() will use the assigned values to instance variables to carry calculation. it should return a string successful or failure.
Now when I enter data in the form, and press submit, it just refreshes the page but nothing is submitted. because it doesn't go to next page :(
Any idea what is happening? I don't need to define a navigation rule, because in other project, I carry out simple calculation and display result in next page and it worsks! Please advice
Thanks,
Your are missing to tell us some of the more important details so the answer is a kind of guesswork.
As you don't use navigation rules I assume you are using JSF 2, aren't you?
With JSF 2 you can directly set the new navigation target, without navigation rules. A forward to "confirmation" should work if your outcome file is named confirmation.xhtml. Check that. With a navigation rule you could forward it do a different file.
This part should work regardless of the rest.
For the bean not getting any values make sure that you are using the correct scope either through annotation or entry in your faces-config.xml. As you have a quite unusal validation mechanism you probably have to use the session scope.
The correct way would be using an actionlistener that does your checks and then sets the navigation depending on your checks. The bean scope could be more restrictive then.
Did you try action="confirmation?faces-redirect=true"?
action method is not called Please refer to this question - , One of my UICommand Component is rendered conditionally , it was said in the answer of the linked question - point 5 - that if the Component's or any of its parents rendered or disabled attributes are false - then the action method will not be called ? If thats the case- How do i achieve the same functionality? Is there a work around ? or a trick ? or any other approach ?
Thanks!
To the point, you'd like to retain the property responsible for the rendered condition in the subsequent request. There are several solutions for this problem:
Put bean in session scope. It's easy, but it hurts. It's bad for user experience since changes will be reflected in all tabs/windows the user has open in the same session.
Use <h:inputHidden> to transfer the property. In theory easy, but in practice it hurts as well. The value will namely get lost whenever a validation/conversion error has occurred in any of other inputs in the same form. This is an odditity in how JSF handles hidden input elements. A workaround is to use <h:inputHidden binding="#{bean.hidden}"> and do a hidden.getValue() and hidden.setValue() in bean.
If you're using <h:commandLink> instead of <h:commandButton>, then you can use <f:param> to transfer the property. It will be available as request parameter, you can check for it in bean's (post)constructor.
Use Tomahawk's <t:saveState>. The perfect solution as far. This will retain the value (or even a complete bean) in the subsequent request.
If you're already on JSF 2.0, the #ViewScoped would have solved this all. It behaves like the <t:saveState>.
See also:
commandButton/commandLink/ajax action/listener method not invoked or input value not updated
The trick is to have 'rendered' evaluate to true when it is time to run the action and then change the condition to false in the action method.
Let's say you have a link rendering based on a boolean in your bean called 'editing'. Then your action would look something like this:
public String myAction() {
// whatever you want your action to do
editing = false;
}
Edit: this assumes that the bean is either session scoped or the boolean get propagated between requests.
In my case, Javascript came for rescue, Which means, whatever was to be displayed conditionally , put them in a HTML Portion and don't display them display: none until the desired event occurs.
HTML Portion can have any JSF Tags(including CommandButtons) as you wish and would work (invoking the action methods and the stuff )perfectly okay.