I got a simple setup (and a big issue): a JSP page with en empty panel grid item container and a binding to a bean.
<h:panelGrid binding="#{ bean.container }" id="container" />
When the getter of the bean will be called, the container is filled with a random number of columns with a command link inside. So far so good. The container is filled up with the right number of elements, and with the use of an ActionListener on the links, I get all click events.
Here comes the tricky part: I want to mark the 'selected' or 'pressed' column via a different style class. With a static setup, I would do this with an expression like:
<h:column styleClass="#{ bean.selectedColumn eq 'id' ? 'btnSelected' : 'btn' }">
<!-- command link and some blahblah -->
</h:column>
The bean contains a simple getter getSelectedColumn() , that returns an id. Straight forward, so this works perfect!
But when I try to do the same inside the bean,
ELContext elContext = FacesContext.getCurrentInstance().getELContext();
String expression = "#{ bean.selectedColumn eq 'id' ? 'btnSelected' : 'btn' }";
new ExpressionFactoryImpl().createValueExpression(elContext, expression, String.class);
column.setValueExpression("styleClass", valueExpression);
the expression won't ever be resolved. To make myself clear: both the command links, the columns and the value expressions are generated inside the bean. Is that the cause?
Can anyone tell me why? Thanks in advance!
When the JSP is compiled the bean wont be called! This is done at runtime cause you want to see live data in the bean. Therefore the (later) generated EL is not visible at compilation. The EL would not be resolved at runtime.
Related
I have the follow situation:
I have a bean that send to form some data, but only in outputlabel the data from the bean is displayed.
I tried to use primefaces, but the same problems persist.
my code:
<h:outputLabel value="#{Bean.name}" id="name2" />
<h:inputText value="#{Bean.name}" id="name" />
<p:inputText value="#{Bean.name}" id="name3" />
Any idea why?
You should have given the bean's code also, to help us better analyze the problem.
Normally you should check for the following:
Check whether you are specifying a correct bean name. Normally
bean's name is same as that of class, except that first letter
should be lowercase. In your case it should be #{bean.name} or else,
specify your custom name with #Named("Bean").
Check whether the getters and setters such as getName() are properly
provided. It may happen that you might have reset the name property in
your bean in the get method itself. Because of which first time it
shows you properly in outputLabel and then in next call to getName it may give you null or empty String. To check this, try put your inputText tag first, and check.
I solve my problem.
When I tried show the values, I was trying recover data from database by pass an ajax action. So, When I clicked at button to retrieve the datas, some of my inputText were set as a required. And because this the data is just displaying into label and not inside of inputtext with required. But because ajax, the request were not called correctly.
When I remove the required from inputtext, it works fine.
I try to create an InputField in the backing bean and add it to the view, but the databinding seems to work just read-only.
I create a UIInput in the Backing-Bean like this:
UIComponent textInput = new UIInput();
textInput.setId("operandInputText");
textInput.setValueExpression("value", ef.createValueExpression(elCtx, "#{row.operandValues[0]}", String.class));
textInput.setValueExpression("rendered", ef.createValueExpression(elCtx, "#{row.inputType == 'text'}", Boolean.class));
mInputPanelGroup.getChildren().add(textInput);
The panelGroup is inside a column of a dataTable and bound to the bean:
<p:column id="operandColumn">
<h:panelGroup id="inputPanelGroup" binding="#{locateEmployeeBean.inputPanelGroup}" >
<h:inputText id="testInput" value="#{row.operandValues[0]}" />
</h:panelGroup>
</p:column>
The <h:inputText/> inside the PanelGroup is just for testing and this is where I found out that the binding I did with setValueExpression(...) works at least read-only.
In the browser I now have 2 inputFields, first the 'testInput' and then 'operandInputText'.
When I enter a value in 'operandInputText' and submit, the value does not get saved, but when I enter a value in the 'testInput'-Field, it get's submitted and in addition the value gets displayed in BOTH inputFields.
The operandValues is a simpe object array:
private Object[] mOperandValues = new Object[2];
Could this have anything to do with the dataType I pass to setValueExpression(...)?
I tried Object, but that didn't change anything.
Any idea why this happens?
Thanks in advance!
I found the solution to my problem. Honestly it was an article by #BalusC Using Datatables: Populate datatable what took me on the right path.
Previously I added the components during PreRenderView-Phase, then I saw in your example that you populate the bound component ONCE in the getter (which is then obviously way earlier during RestoreView-Phase). That is how I've done it now and it works flawlessly, the Inputfields now work both ways (read+write).
Thanks alot for your work #BalusC!
I'm trying to figure out why an f:attribute tag's value isn't passed when attached to h:inputSecret tag. I'm quite new to jsf, but as far as I know attributes can be attached to any kind of component. Here is the code:
<h:inputSecret id="passw" value="#{advertAdder.userPass}"
required="true" validator="#{advertAdder.validatePasswords}">
<f:attribute name="confirmedPass" value="#{advertAdder.passConfirmator.value}"/>
</h:inputSecret>
<h:inputSecret id="passwConfirm" required="true"
binding="#{advertAdder.passConfirmator}"/>
and the method that wants to acces this attribute:
public void validatePasswords(FacesContext context, UIComponent component, Object value)
{
if (!value.equals(component.getAttributes().get("confirmedPass")))
{
FacesMessage mess = new FacesMessage("Password and it's confirmation are not the same!");
context.addMessage(component.getClientId(context), mess);
((UIInput) component).setValid(false);
}
}
In above code component.getAttributes() always returns map with only two attributes:
javax.faces.component.VIEW_LOCATION_KEY and com.sun.faces.facelets.MARK_ID.
I've added attribute tag to a h:commandButton to check it, and then everything was fine. Am I missing something or it's not possible to add an attribute to non-action tag?
I'm using Mojarra 2.0.2 and Glassfish 3.0.1.
Thanks in advance.
Input components are processed in the order as they appear in the component tree. The UIInput#getValue() is only available when the component is already been processed. Otherwise you need to use UIInput#getSubmittedValue() instead.
<f:attribute name="confirmedPass" value="#{advertAdder.passConfirmator.submittedValue}"/>
Note that this gives you the unconverted and unvalidated value back. It would make somewhat more sense to put the validator on the confirm password field instead and pass the value of the first password field along. See also JSF Validator compare to Strings for Equality and JSF doesn't support cross-field validation, is there a workaround?
Alternatively, you can also try out the OmniFaces <o:validateEqual> component. You can find a concrete example in this article.
Unrelated to the concrete problem, it's unnecessary to bind the component to the bean this way. Replace all occurrences of #{advertAdder.passConfirmator} by #{passConfirmator}. Keep the controller free of properties which are never internally used.
I searched everywhere but could not find a solution to this. I am trying to used
required=yes to validate whether a value is present or not. I am using it inside inputtext.
The problem is it does not work inside a datatable. If I put the text box outside the datatable it works. I am using JSF 1.7 so I don't have the validateRequired tag from JSF 2.0.
I even used a validator class but it is still not working. Does anyone know why does required=yes or validator='validationClass' inside a inputtext inside a datatable is not working.
I appreciate the help.
Thanks.
First of all, the proper attribute values of the required attribute are the boolean values true or false, not a string value of Yes. It's an attribute which accepts a boolean expression.
The following are proper usage examples:
<h:inputText required="true" />
<h:inputText required="#{bean.booleanValue}" />
<h:inputText required="#{bean.stringValue == 'Yes'}" />
As to the problem that it doesn't work inside a <h:dataTable>, that can happen when the datamodel is not been preserved properly (the datamodel is whatever the table retrieves in its value attribute). That can in turn happen when the managed bean is request scoped and doesn't prepare the datamodel during its (post)construction which causes that the datamodel is null or empty while JSF is about to gather, convert and validate the submitted values.
You need to ensure that the datamodel is exactly the same during the apply request values phase of the form submit request as it was during the render response phase of the initial request to display the form with the table. An easy quick test is to put the bean in the session scope. If that fixes the problem, then you definitely need to rewrite the datamodel preserving logic. You could also use Tomahawk's <t:saveState> or <t:dataTable preserveDataModel="true"> to store the datamodel in the view scope (like as JSF2's new view scope is doing).
Finally, JSF 1.7 doesn't exist. Perhaps you mean JSF 1.2?
HI,
Please see the following code:
<h:selectOneMenu id="countries" value="#{countryBean.selectedCountry}" onchange="submit()
valueChangeListener="#{countryBean.changeCountry}">
<f:selectItems value="#{countryBean.countries }" />
</h:selectOneMenu>
Backing Bean
public void changeCountry(ValueChangeEvent event){
String newValue = (String)event.getNewValue();
String oldValue = (String)event.getOldValue();
System.out.println("New Value : " + newValue);
System.out.println("Old Value : " + oldValue);
if ("1".equals(newValue)){
this.countries = new ArrayList<SelectItem>();
this.cities.add(new SelectItem("1","Delhi"));
this.cities.add(new SelectItem("2","Mumbai"));
}
if ("2".equals(newValue)){
this.cities = new ArrayList<SelectItem>();
this.cities.add(new SelectItem("1","Mossco"));
}
}
Please let me know if the implementation is correct. It is working fine.
My questions are:
What is the advantage of adding the f:valueChangeListener tag inside the h:selectOneMenu tag. I have used the normal attribute valueChangeListener="#{countryBean.changeCountry}".
Is it necessary to use onchange="submit() this code to change the values.
What is difference between writing the custom listeners by implementing the ActionListener interface and just using the attribute in the UIComponent tags (action="methodName").
Please explain me.
The ValueChangeListener will only be called when the form is submitted, not when the value of the input is changed. Thus, if you want to run this listener when the value is modified, you have two solutions:
Submit your form when the onchange event is fired (this is what you did in your code);
Use an Ajax call instead, by using some dedicated components (already integrated in JSF2, with <f:ajax>, or third-parties libraries such as Richfaces, Primefaces...).
Here is an example with Richfaces:
<h:selectOneMenu id="countries" value="#{countryBean.selectedCountry}" valueChangeListener="#{countryBean.changeCountry}">
<a4j:support event="onchange" .../>
<f:selectItems value="#{countryBean.countries }" />
</h:selectOneMenu>
Regarding the code of your listener, it seems correct, but why question is why do you need a ValueChangeListener here? Indeed, this listener is usefull when you want to track a modification of a value. That's why the ValueChangeEvent provides both getOldValue() and getNewValue() methods.
In your code, you do not care about the old value, so basically, you could "simply" do an action instead of a valueChangeListener (ex. with Richfaces):
<h:selectOneMenu id="countries" value="#{countryBean.selectedCountry}">
<a4j:support event="onchange" actionListener="#{countryBean.changeCountry}"/>
<f:selectItems value="#{countryBean.countries }" />
</h:selectOneMenu>
Finally, regarding the difference between the valueChangeListener attribute and <f:valueChangeListener> is that the first binds a Java method (#{myBean.myMethod}), while the second binds a Java class (type="com.foo.MyListenerClass") which implements the ValueChangeListener interface. So the second one could be more generic than the first one...
Romaintaz already pointed out the most, I just wanted to get straight on your concrete questions:
What is the advantage of adding the f:valueChangeListener tag inside the h:selectOneMenu tag. I have used the normal attribute valueChangeListener="#{countryBean.changeCountry}".
As Romaintaz said, the attribute points to a method and the f: tag points to a class. Another advantage is that you can have multiple of them, whenever that is necessary.
Is it necessary to use onchange="submit() this code to change the values.
That Javascript doesn't change the values. That Javascript submits the entire form without the need to pressing the submit button yourself, whenever the value has been changed by the enduser. No, that is not necessary. You can also just remove it and expect that the enduser presses the submit button himself. Once again, that JavaScript is not part of JSF.
What is difference between writing the custom listeners by implementing the ActionListener interface and just using the attribute in the UIComponent tags (action="methodName").
This question is already asked before: difference between action and actionlistener.
The solution from romaintaz of calling an action instead of valueChangeListener is also great because in the case of "change" event the action is called after the model is updated (allowing for a DB update for example) while the valueChangeListener is called before....