Get primefaces widgetVar in javascript and update it

Question

I have a primefaces component like this:

<p:panel styleClass="errorsPanelClass" id="errorsPanel" header="Messages" toggleable="true" effect="drop" toggleSpeed="0" closeSpeed="0" widgetVar="errorsPanelWidget">

and i'm trying to get the component in javascript context and update it.

I already tried with:

function getWidgetVarById(id) {
   for (var propertyName in PrimeFaces.widgets) {
     if (PrimeFaces.widgets[propertyName].id === id) {
       return PrimeFaces.widgets[propertyName];
     }
   }
}

or

How to find a widgetVar?

or

Get widgetVar with JavaScript or check/uncheck all other PrimeFaces checkboxes

It will be great if I'll find a solution to take the widgetVar by class, but any other solutions are welcomed.

I also tried:

function getWidgetVarById() {
    for ( var propertyName in PrimeFaces.widgets) {
        alert(PrimeFaces.widgets[propertyName].id);
    }
}

but I get an javascript error "'PrimeFaces.widgets.length' is null or not an object"

Any ideas?

Answer 1

There is not mapping between the id and a widgetVar for PrimeFaces 3.5. In 3.5 the widgets are added to the 'window' object and not stored somewhere else. This means that the widgetVar is already directly a variable u can use.

<p:panel id="errorsPanel" widgetVar="errorsPanelWidget">

3.5/4.0: (in 4.0 this still works but is deprecated in favour of the PF('..') way) errorsPanelWidget.close()

5.0 and up: PF('errorsPanelWidget').close() (unless you configure the legacy mode after which it will behave like 3.5/4.0)

Easiest is then to use a convention that you name your widgetVar like your id but with a postfix e.g. id_widget. You could (advise against it) leave the widgetVar out and then the widget is idententical to the id (this can cause classhes in cases, that is why PF dropped this convention).

And you could still check if in 3.5 the widgetVar value is in one way or another added to the outer html element of the widget. You could then retrieve it with some jquery. Personally, I used the 'convention' way in previous PF versions (appending 'Widget' to the value that is also in the id and putting that in the widgetVar attribute)

And if with 'updating' the widget, you mean updating the content of the widget, you can't. There is no refresh() kind of method that does this. What you could do is send the id(!) to the server and execute an update(..) there via the requestContext like this

RequestContext context = RequestContext.getCurrentInstance();
context.update("errorsPanel");

But it might be even better to just to this the moment you update the list serverside. So it might be that you've fallen into the XY trap.

But if it is really needed, here is an example that works, using the PrimeFaces extensions remoteCommand since that is the easiest way)

xhtml:

<pe:remoteCommand id="refreshWidgetCommand" name="refreshWidget" process="@this" actionListener="#{updateWidgetController.refresh}">  
    <pe:methodSignature parameters="java.lang.String"/>  
    <pe:methodParam name="id"/>  
</pe:remoteCommand>  

Bean:

@ManagedBean  
@RequestScoped  
public class UpdateWidgetController {  

    public void refresh(final String id) {  

        RequestContext context = RequestContext.getCurrentInstance();
        context.update(id);
    }
}

calling refreshWidget('errrosPanel'); will achieve what you want.

Don't wan't to use PFE (or can't use this due to version incompatibilities), you can achieve the same with PF remoteCommand But the specific example for 3.5 might differ a little