How to render different pages from the SelectOneMenu

[Mikel Martin]

Hello,

I am trying to find out a way to render different xhtml pages according to the selected value.

In my web it would be to render the page in a language or other depending of the value selected in the drop-down menu.

I tried the following:

In the XHTML I would use the UIComponent SelectOnMenu with different values related to the different languages.

<h:selectOneMenu id="lang_menu" value="#{languageControl.languageOption}"  >
                    <f:selectItem  itemValue="item1" itemLabel="ENGLISH"   />
                    <f:selectItem itemValue="item2" itemLabel="CASTELLANO" />
</h:selectOneMenu>

And the Managed Bean:

@ManagedBean 
@RequestScoped
public class languageControl {

    private String languageOption;
    

    public languageControl() {
        
    }

    public String getLanguageOption() {
        if(languageOption=="item1"){return "index.xhtml";}
        else { return "index_ES.xhtml";}
  }

    public void setLanguageOption(String languageOption) {
        this.languageOption = languageOption;
    }

  }

This does not work. My question is how could I render the two differents XHTML according to the different option values of the UIComponent.

[Bin Smith]

Hello!

You can use ajax for this!

You can create one big page that includes two parts. One part for one page and it is rendered by condition
<h:panelGroup rendered="#{backingBean.firstRendered">
</h:panelGroup>

Anothe part of the same page is rendered by:
<h:panelGroup rendered="#{! backingBean.firstRendered">
</h:panelGroup>

Clicking on h:selectonemenu option you call listener of f:ajax and set backingBean.firstRendered to true or false and in render attribute of f:ajax you specify main wrapper for both parts

[Mikel Martin]

Many thanks for the answer.

As I am a newbie in J.S.F. I have been carefully examining your answer, but I got stucked in the last part of the answer (f:ajax).

I have written the following for the drop-down menu:

<h:selectOneMenu id="lang_menu"   >
                    <f:selectItem  itemValue="item1" itemLabel="ENGLISH" />
                    <f:selectItem itemValue="item2" itemLabel="CASTELLANO" />
                    <f:ajax execute="@this" listener="#{languageControl.firstRendered}"  render="english spanish" />
</h:selectOneMenu>

being english and spanish of the render attribute the id´s of the panel group when the firstRender method is false or true respectively.


But I can´t figure out how to make one or other render calling the firstRendered method in f:ajax

Many thanks

[Tim Holloway]

I haven't been able to use the f:ajax tag for technical reasons, so I am no expert, but it's possible that you may need to inform it what sort of event will fire the firstRendered method.

Try coding 'event="change"' on your f:ajax tag.

[Bin Smith]

Hello!

f:ajax you should set as this:

<f:ajax execute="@this" event="change" listener="#{languageControl.changePage}" render="yourFormID:english yourFormID:spanish" />

Your form should look like this

<f:form id="yourFormID">
<h:panelgroup id="english" rendered="#{languageControl.firstRendered}">
...................
</h:panelgroup>

<h:panelgroup id="spanish" rendered="#{! languageControl.firstRendered}">
...................
</h:panelgroup>

</f:form>

Your method listener inside LanguageControl backing bean should look similar to:

public void changePage(){
this.firstRendered=! firstRendered;
}

getter and setter of firstRendered property

[Tim Holloway]

Volodymyr, you might want to read this: https://coderanch.com/how-to/java/UseCodeTags

[Bin Smith]

Whenever I try to use code button it gives me some error.

In really rare situations I can apply it!

[Tim Holloway]

Volodymyr Levytskyi wrote:Whenever I try to use code button it gives me some error.

In really rare situations I can apply it!

What is "some error"

If you get the "Pants Down" error, that's because our database connection pool ran dry again and it has nothing to do with anything you did. We've been working hard on tuning connection usage lately.