Af:table: copy values of currently selected row to other attribute bindings

Question

Hello,
I'm using JDev 11g.
Copying a value from one attribute value binding to another one is easy when you are clicking a button, with a setActionListener:
<af:setActionListener from="#{bindings.SourceField.inputValue}" to="#{bindings.DestinationField.inputValue}"/>What I want to do is the same behaviour, but instead of clicking a button, the triggering event should be the selection of a row on an af:table. The source field is a column of the currently selected row. The destination is another attribute value binding outside of the table.
Jspx:
<af:table value="#{bindings.EmployeesView1.collectionModel}" var="row">
  <af:column ... >
    <af:inputText value="#{row.bindings.SourceField.inputValue}" ... />
  </af:column>
</af:table>
<af:inputText ... value="#{bindings.DestinationField.inputValue}" />
...Page Def:
<bindings>
  <tree IterBinding="EmployeesView1Iterator" id="EmployeesView1">
    <nodeDefinition ... >
      <AttrNames>
        <Item Value="SourceField"/>
      </AttrNames>
    </nodeDefinition>
  </tree>
  <attributeValues IterBinding="EmployeesView1Iterator" id="SourceField">
    <AttrNames>
      <Item Value="SourceField"/>
    </AttrNames>
  </attributeValues>
  <attributeValues IterBinding="SomeOtherIterator" id="DestinationField">
    <AttrNames>
      <Item Value="DestinationField"/>
    </AttrNames>
  </attributeValues>
</bindings>What needs to happen in this simplified case is everytime a row is selected in the table, the value of the SourceField column (that also has an attribute value binding) should be copied to the DestinationField of some other iterator. Analogous to the setActionListener, but without a button. And in the real case, there are more columns of the selected row that need to be copied to more fields.
How can this be done? I already created a custom selectionListener for the table in a backing bean. In this selectionListener, the first thing I do is call the default "#{bindings.EmployeesView1.collectionModel.makeCurrent}". Then I fetch the current row, which is also no problem. So I now have access to the value of SourceField in my selectionListener in the backing bean. The only thing that is left now is copying this value to the "#{bindings.DestinationField.inputValue}" in Java, and that's where I'm stuck. :-)
Or even better ofcourse, is there a declarative way to do this without Java code?
Help would be greatly appreciated!
Chris

Answer 1

Hi Chris,
You should be able to use this utility method from JSFUtils class (part of FOD)
    public static void setExpressionValue(String expression, Object newValue) {
        FacesContext facesContext = getFacesContext();
        Application app = facesContext.getApplication();
        ExpressionFactory elFactory = app.getExpressionFactory();
        ELContext elContext = facesContext.getELContext();
        ValueExpression valueExp =
            elFactory.createValueExpression(elContext, expression,
                                            Object.class);
        //Check that the input newValue can be cast to the property type
        //expected by the managed bean.
        //If the managed Bean expects a primitive we rely on Auto-Unboxing
        Class bindClass = valueExp.getType(elContext);
        if (bindClass.isPrimitive() || bindClass.isInstance(newValue)) {
            valueExp.setValue(elContext, newValue);
    }edit... just realized you need this too
    public static FacesContext getFacesContext() {
        return FacesContext.getCurrentInstance();
    }John