I am learning JSF and when I send an object to a bean parameter the instance of the object is not correct.
I have a page that list a lot of movies, if I want to see the complete information about a movie, I click on a link that send me to a page with this code:
<h:form>
<h:commandLink action="#{sharedMovie.share(movie)}" value="Share">
<div class="movieDetail">
<div class="movieDetailTitle">"#{movie.title}"</div>
<div class="movieDetailYear">"#{movie.year}"</div>
<div class="movieDetailSynopsis">"#{movie.synopsis}"</div>
</div>
</h:form>
The movie bean have a request scope.
The problem is that when I click on "Share" my class sharedMovie receives a new instance of Movie, instead of the displayed movie in the page. All the displayed data is correct, only when I call the other page that this problem happens.
I already tried sending just the movie ID (but it is always 0), using f:setPropertyActionListener, f:param, but nothing works. If I debug my project, when I click on share link it always hit the breakpoint inside the constructor of Movie class.
How I can pass this instance correctly?
Related
This question already has an answer here:
How to call JSF backing bean method only when onclick/oncomplete/on... event occurs and not on page load
(1 answer)
Closed 5 years ago.
<h:outputLink value="/4JVA-157292-war/supinfo/auth/mycar.xhtml">Car</h:outputLink>
<h:outputLink value="Log Out" onclick="${loginController.logout()}" />
As you see, If i click the Car link. I will excute the ${loginController.logout()}, but if i delete the Log out. I will go into the car page.
<h:ouputLink> component is used to render plain a anchor element with its href attribute evaluated as value attribute of <h:outputLink> with the query parameters attached in case the component has <f:param> tags as its children.
<h:ouputLink> is not used to execute server-side actions as you wrongly seemed to expect. You may have confused it with a <h:commandLink> component that is used to trigger a server-side action via a JavaScript call.
If you want to call the action method you must switch to a command comnponent (or its derivative) like <h:commandLink>. Its action attribute should point to the desired action method, like so:
<h:commandLink value="Log out" action="#{loginController.logout}" />
In this way you will be able to execute the bean action method.
Also it is worth noting that since JSF 2.0 there has been an <h:link> component that is useful for handling application-wide navigation. It takes a navigation case outcome in its outcome attribute thus leaving <h:outputLink> component useful for links to external resources.
For more information on the subject read the following answer: When should I use h:outputLink instead of h:commandLink?.
As to the cause of the problem you faced, onclick attribute is rendered as onclick event handler of the generated a element that responds to a click event on the HTML element it is attached to. In case the event is fired a client-side JavaScript code is called (by function call onclick points to or by executing inline code that is contained therein). Do note that onclick runs on the client (in JavaScript context within web browser) while action runs on the server (executes Java code depending on the submit button pressed within web server).
Usage of onclick may be fruitful at least in the following circumstances:
in case it is used in conjunction with a command component it may stop form submission to the server if some client-side requirements are not met (i.e. confirm dialog was shown and cancel button was pressed, or client-side validation failed) as soon as the event will be fired before any consecutive events associated with the element (like form submission):
<h:commandLink value="Delete item" action="#{bean.delete(item)}" onclick="return confirm("Are you sure you want to delete this item?");" ... />
or
<h:commandLink value="Submit data" action="#{bean.action}" onclick="return inputValid();" ... />
with
<script type="text/javascript">
function inputValid() {
var isInputValid = ...;
//decide what's valid or not and set variable to true/false accordingly
return isInputValid;
}
</script>
it may be used to trigger some GUI changes, especially when used in conjunction with non-command components, like in:
<h:button value="Show dialog" onclick="showDialog(); return false;" ... />
I'm trying to call a managed bean from h:commandLink in JSF. But I don't see href attribute in the rendered HTML a tag.
Am I missing something?
There is a ManagedBean called AccountSetupController with a signUp method in it.
This is the tag I used in JSF:
<h:form prependId="false">
<h:commandLink action="#{accountSetupController.signUp()}"
value="#{msg['homepage.createaccount']}" styleClass="button large">
</h:commandLink>
</h:form>
This is the rendered tag. See there is nothing in href attribute.
<a href="#" onclick="mojarra.jsfcljs(document.getElementById('j_idt15'),
{'j_idt33':'j_idt33'},'');return false"
class="button large">CREATE MY ACCOUNT</a>
This is the form tag that is generated
<form id="j_idt15" name="j_idt15"
method="post" action="/myproject/faces/homepage/homepage.xhtml"
enctype="application/x-www-form-urlencoded"> .... </form>
As you can see, the form action is pointing to some place I don't need.
Am I missing something?
Command links in JSF are rendered that way. The form will be submitted by JSF via JavaScript's onclick method using JSF JS library, while the href will always stay #.
Moreover, you won't find the bound action / action listener method names in browser tools due to understandable reasons. Rather, JSF will find the id of a clicked link on the server and will trigger all of the component's action(listeners).
All in all, reading <h:commandLink> documentation unsurprisingly helps a lot (all emphasis mine):
General behavior: Both the encode and decode behavior require the ability to get the id/name for a hidden field, which may be rendered in markup or which may be programmatically added via client DOM manipulation, whose value is set by the JavaScript form submit (further referred to as hiddenFieldName.
Decode behavior: Obtain the "clientId" property of the component. Obtain the Map from the "requestParameterMap" property of the ExternalContext. Derive hiddenFieldName as above. Get the entry in the Map under the key that is the hiddenFieldName. If the there is no entry, or the entry is the empty String, or the entry is not equal to the value of the "clientId" property, return immediately. If there is an entry, and its value is equal to the value of the "clientId" property, create a new javax.faces.event.ActionEvent instance around the component and call queueActionEvent() on the component, passing the event.
Encode behavior: Render "#" as the value of the "href" attribute. Render the current value of the component as the link text if it is specified. Render JavaScript that is functionally equivalent to the following as the value of the "onclick" attribute: document.forms['CLIENT_ID']['hiddenFieldName'].value='CLIENT_ID'; ocument.forms['CLIENT_ID']['PARAM1_NAME'].value='PARAM1_VALUE'; document.forms['CLIENT_ID']['PARAM2_NAME'].value='PARAM2_VALUE'; return false; document.forms['CLIENT_ID'].submit()" where hiddenFieldName is as described above, CLIENT_ID is the clientId of the UICommand component, PARAM*_NAME and PARAM*_VALUE are the names and values, respectively, of any nested UIParameter children.
In JSF 2, what is the difference between h:button and h:commandButton ?
<h:button>
The <h:button> generates a HTML <input type="button">. The generated element uses JavaScript to navigate to the page given by the attribute outcome, using a HTTP GET request.
E.g.
<h:button value="GET button" outcome="otherpage" />
will generate
<input type="button" onclick="window.location.href='/contextpath/otherpage.xhtml'; return false;" value="GET button" />
Even though this ends up in a (bookmarkable) URL change in the browser address bar, this is not SEO-friendly. Searchbots won't follow the URL in the onclick. You'd better use a <h:outputLink> or <h:link> if SEO is important on the given URL. You could if necessary throw in some CSS on the generated HTML <a> element to make it to look like a button.
Do note that while you can put an EL expression referring a method in outcome attribute as below,
<h:button value="GET button" outcome="#{bean.getOutcome()}" />
it will not be invoked when you click the button. Instead, it is already invoked when the page containing the button is rendered for the sole purpose to obtain the navigation outcome to be embedded in the generated onclick code. If you ever attempted to use the action method syntax as in outcome="#{bean.action}", you would already be hinted by this mistake/misconception by facing a javax.el.ELException: Could not find property actionMethod in class com.example.Bean.
If you intend to invoke a method as result of a POST request, use <h:commandButton> instead, see below. Or if you intend to invoke a method as result of a GET request, head to Invoke JSF managed bean action on page load or if you also have GET request parameters via <f:param>, How do I process GET query string URL parameters in backing bean on page load?
<h:commandButton>
The <h:commandButton> generates a HTML <input type="submit"> button which submits by default the parent <h:form> using HTTP POST method and invokes the actions attached to action, actionListener and/or <f:ajax listener>, if any. The <h:form> is required.
E.g.
<h:form id="form">
<h:commandButton id="button" value="POST button" action="otherpage" />
</h:form>
will generate
<form id="form" name="form" method="post" action="/contextpath/currentpage.xhtml" enctype="application/x-www-form-urlencoded">
<input type="hidden" name="form" value="form" />
<input type="submit" name="form:button" value="POST button" />
<input type="hidden" name="javax.faces.ViewState" id="javax.faces.ViewState" value="...." autocomplete="off" />
</form>
Note that it thus submits to the current page (the form action URL will show up in the browser address bar). It will afterwards forward to the target page, without any change in the URL in the browser address bar. You could add ?faces-redirect=true parameter to the outcome value to trigger a redirect after POST (as per the Post-Redirect-Get pattern) so that the target URL becomes bookmarkable.
The <h:commandButton> is usually exclusively used to submit a POST form, not to perform page-to-page navigation. Normally, the action points to some business action, such as saving the form data in DB, which returns a String outcome.
<h:commandButton ... action="#{bean.save}" />
with
public String save() {
// ...
return "otherpage";
}
Returning null or void will bring you back to the same view. Returning an empty string also, but it would recreate any view scoped bean. These days, with modern JSF2 and <f:ajax>, more than often actions just return to the same view (thus, null or void) wherein the results are conditionally rendered by ajax.
public void save() {
// ...
}
See also:
How to navigate in JSF? How to make URL reflect current page (and not previous one)
When should I use h:outputLink instead of h:commandLink?
Differences between action and actionListener
h:button - clicking on a h:button issues a bookmarkable GET request.
h:commandbutton - Instead of a get request, h:commandbutton issues a POST request which sends the form data back to the server.
h:commandButton must be enclosed in a h:form and has the two ways of navigation i.e. static by setting the action attribute and dynamic by setting the actionListener attribute hence it is more advanced as follows:
<h:form>
<h:commandButton action="page.xhtml" value="cmdButton"/>
</h:form>
this code generates the follwing html:
<form id="j_idt7" name="j_idt7" method="post" action="/jsf/faces/index.xhtml" enctype="application/x-www-form-urlencoded">
whereas the h:button is simpler and just used for static or rule based navigation as follows
<h:button outcome="page.xhtml" value="button"/>
the generated html is
<title>Facelet Title</title></head><body><input type="button" onclick="window.location.href='/jsf/faces/page.xhtml'; return false;" value="button" />
This is taken from the book - The Complete Reference by Ed Burns & Chris Schalk
h:commandButton vs h:button
What’s the difference between h:commandButton|h:commandLink and
h:button|h:link ?
The latter two components were introduced in 2.0 to enable bookmarkable
JSF pages, when used in concert with the View Parameters feature.
There are 3 main differences between h:button|h:link and
h:commandButton|h:commandLink.
First, h:button|h:link causes the browser to issue an HTTP GET
request, while h:commandButton|h:commandLink does a form POST. This
means that any components in the page that have values entered by the
user, such as text fields, checkboxes, etc., will not automatically
be submitted to the server when using h:button|h:link. To cause
values to be submitted with h:button|h:link, extra action has to be
taken, using the “View Parameters” feature.
The second main difference between the two kinds of components is that
h:button|h:link has an outcome attribute to describe where to go next
while h:commandButton|h:commandLink uses an action attribute for this
purpose. This is because the former does not result in an ActionEvent
in the event system, while the latter does.
Finally, and most important to the complete understanding of this
feature, the h:button|h:link components cause the navigation system to
be asked to derive the outcome during the rendering of the page, and
the answer to this question is encoded in the markup of the page. In
contrast, the h:commandButton|h:commandLink components cause the
navigation system to be asked to derive the outcome on the POSTBACK
from the page. This is a difference in timing. Rendering always
happens before POSTBACK.
Here is what the JSF javadocs have to say about the commandButton action attribute:
MethodExpression representing the application action to invoke when
this component is activated by the user. The expression must evaluate
to a public method that takes no parameters, and returns an Object
(the toString() of which is called to derive the logical outcome)
which is passed to the NavigationHandler for this application.
It would be illuminating to me if anyone can explain what that has to do with any of the answers on this page. It seems pretty clear that action refers to some page's filename and not a method.
I have to perform two operations on button click.
call a method in a bean which will return a url and it will be set in some variable.
after that I have to open that url in another tab. I am using the action attribute of CommandButton and it is setting the URL value correctly, but how do I open that url as pdf in a new tab. i.e "URL of pdf should open in a new tab"
Code sample as follows:
<div class="form-options">
<h:commandButton value="Download Report" styleClass="btn btn-primary btn-icon buttonCustom" actionListener="#{reportBean.GenerateReport}">
</h:commandButton>
</div>
Hope I unterstood you right. This worked for me:
Provide the method generating the report and the URL in the actionListener-attribute of the commandButton (what you already did, according to your sample code).
Provide the method returning the URL in the action-attribute of the commandButton (it will be called after the actionListener-method).
For opening a new tab, add target="_blank in the parent <h:form> (taken from this questions answer)
XHTML-Code:
<h:form target="_blank">
<h:commandButton value="Show Report"
actionListener="#{reportBean.generateReport}"
action="#{reportBean.getUrl}" />
</h:form>
As this approach applies the target="_blank" to all non-ajax calls, here's another way using Javascript:
<h:form>
<h:commandButton value="Show Report"
actionListener="#{reportBean.generateReport}"
action="#{reportBean.getUrl}"
onclick="this.form.target='_blank'"/>
</h:form>
Java-Code:
public void generateReport(final ActionEvent evt) {
// ... generating report and setting url-variable
}
public String getUrl() {
return url;
}
If you have to forward to an external link, see this question
Use commandLink instead of commandButton..
When commandLink is used you need to provide value for target attribute as new window.
<h:commandLink target="new window">
Rest all the code will be as per your requirement.
Since the URL in which your report is present is already present in one of the variables you can use this variable from the bean in commandLink to provide the URL..
Elsewhile you can use an iframe also.It is generally used to display the report on the same page...
As I understand, your problem is not about redirecting the result of the action to a new tab, instead you want to show a report (if my guessing is right, you're using a JasperReport and want to show it in PDF format). To do this, you must download the file to the client computer and then let the default editor/program on the client handle the file.
I won't go into details for file download, BalusC provides good info about this matter:
How to stream a file download in a JSF backing bean?
How to download a file stored in a database with JSF 2.0
The relevant part to show PDF (or any other) files in browser is the ContentType of the response. This will say to the browser how the file must be threatened. Some content type values
PDF: application/pdf
Excel: application/vnd.ms-excel
Microsoft Word: application/ms-word
More: Internet media type
In case I'm wrong and you don't want to show (download) the file and need to open the file in a new Window, you have two ways (resuming both #JanisK. and #AngelsandDemons answers):
Setting the target of the form as "_blank", but this way will do that all the performed actions will open a new tab/window.
<h:form target="_blank">
<h:commandButton ... />
</h:form>
Using a commandLink instead of a commandButton, where you can set the target only for this link requests.
<h:form>
<h:commandLink target="_blank" ... />
</h:form>
I am trying to popup a window when someone clicks a button on the data table.
<h:commandButton
action="#{cacheController.popupDetails}"
immediate="false"
onclick="popup()"
value="View Details"
styleClass="submit">
</h:commandButton>
The associated popup function is
function popup() {
window.open('RDDetails.jsf','popupWindow', 'dependent=yes, menubar=no, toolbar=no, height=500, width=400');
}
Now in the new 'RDDetails.jsf" file, I am trying to access the same managedBean cacheController. But the problem is, the pop-up window and JSF lifecycle is not in sync. As a result, the popup first displays blank and when I refresh, it pulls out the proper data.
Is there anyway I can click on a button which will do some processing in the managed bean and then opens a pop up which rerieves the processed data from the managed bean.
I am using JSF 1.1.
You're here basically firing two independent requests: one associated with the form submit and other which opens the RDDetails.jsf in a popup. You'll need to combine this in one request. You can achieve this in basically two ways:
Get rid of the onclick and just add target="_blank" to the <h:form> so that it get submitted into a new window/tab.
Block the default action by adding return false; to the onclick and do the business logic in the constructor of the bean associated with RDDetails.jsf. The only (major) caveat is here that the model won't be updated with the form fields. Thus, you'll need to pass the form fields as request parameters of the popup URL manually with help of JavaScript. You can then make use of managed property entries in the faces-config.xml to inject the GET request parameters into the model.
First way is obviously the easiest, but this doesn't give you a "fullworthy" popup/modal dialog. The second way is a bit harder (unless you've already a good grasp on both JavaScript and JSF). I would then consider to look for a component library which provides a ready-to-use popup component.
See my example:
<h:commandLink action="#{controller.myAction}" onmousedown="document.forms['idform'].target='_blank';">
I'm using jsf 1.1