PrimeFaces dataTable with variable columns and specific editable cells

Question

I need to create a table where the headers list are brought from a model. The table contents are also stored in the model and p:dataTable loop on the data to show the conten

Answer 1

The input component's value must be bound to a writable value expression. What you've there is a direct getter method invocation and thus essentially read-only. This is indeed not going to work. You need to specify a property name of the #{entity}. You can use the brace notation to specify the property name as a variable like so #{entity[propertyName]}.

So, basically:

<p:dataTable value="#{bean.entities}" var="entity" editable="true" editMode="cell">
    <p:columns value="#{bean.propertyNames}" var="propertyNames">
        <p:cellEditor>
            <f:facet name="output">
                #{entity[propertyName]}
            </f:facet>
            <f:facet name="input">
                <p:inputText value="#{entity[propertyName]}" />
            </f:facet>
        </p:cellEditor>
    </p:columns>
</p:dataTable>

As to the column header, rather refactor out that into a Map<String, String> where the key is the propertyName and the value is the header.

        <f:facet name="header">
            #{bean.columnHeaders[propertyName]}
        </f:facet name="header">

Or better yet, use a normal i18n resource bundle for that where the propertyName represents part of the bundle key.

        <f:facet name="header">
            #{bundle['table.column.header.' += propertyName]}
        </f:facet name="header">

As to the editable check, rather wrap propertyName and editable in another bean (and perhaps also columnHeader if you don't want to use a i18n bundle), e.g. Field and then use like below:

    <p:columns value="#{bean.fields}" var="field">
        <p:cellEditor>
            <f:facet name="output">
                #{entity[field.propertyName]}
            </f:facet>
            <f:facet name="input">
                <p:inputText value="#{entity[field.propertyName]}" rendered="#{entity[field.editable]}" />
            </f:facet>
        </p:cellEditor>
    </p:columns>

All in all, it just boils down to preparing and providing the right model the view expects. This way the getData() thing isn't necessary.