Primefaces tooltip for p:selectManyCheckbox

问题:

I would like to add a tooltip for each element in a p:selectManyCheckBox. However I can't come up with a solution.

I've got a class Role that has 3 properties, "id" (Long), "name" (String) and "description" (String). The name is displayed and I would like to have the description as a tooltip.

This is a working piece of code:

<p:selectManyCheckbox layout="pageDirection" value="#{roleBean.selectedRoles}" converter="roleConverter">
    <f:selectItems value="#{roleBean.roles}" var="role" itemLabel="#{role.name}" itemValue="#{role}"/>
</p:selectManyCheckbox>

The roleConverter is a FacesConverter that converts the Role to an id and visa versa.

I came up with this:

<p:selectManyCheckbox layout="pageDirection" value="#{roleBean.selectedRoles}" converter="roleConverter">
    <c:forEach var="role" items="#{roleBean.roles}">
        <f:selectItem id="role#{role.id}" itemLabel="#{role.name}" itemValue="#{role}" />
        <p:tooltip for="role#{role.id}" value="#{role.description}"/>
    </c:forEach>
</p:selectManyCheckbox>

But unfortunately it doesn't work.

回答1:

You can achieve this by (ab)using the unused(!) SelectItem#getDescription() property as below:

<p:selectManyCheckbox layout="pageDirection" value="#{roleBean.selectedRoles}" converter="roleConverter">
    <f:selectItems value="#{roleBean.roles}" var="role" 
        itemValue="#{role}" itemLabel="#{role.name}" itemDescription="#{role.description}" />
</p:selectManyCheckbox>

And overriding the PrimeFaces SelectManyCheckboxRenderer#encodeOptionLabel() as below to recognize and render it:

public class YourSelectManyCheckboxRenderer extends SelectManyCheckboxRenderer {

    @Override
    protected void encodeOptionLabel(FacesContext context, SelectManyCheckbox checkbox, String containerClientId, SelectItem option, boolean disabled) throws IOException {
        ResponseWriter writer = context.getResponseWriter();
        writer.startElement("label", null);
        writer.writeAttribute("for", containerClientId, null);

        if (option.getDescription() != null) {
            writer.writeAttribute("title", option.getDescription(), null);
        }

        if (disabled) {
            writer.writeAttribute("class", "ui-state-disabled", null);
        }

        if (option.isEscape()) {
            writer.writeText(option.getLabel(), null);
        } else {
            writer.write(option.getLabel());
        }

        writer.endElement("label");
    }

}

Which is registered as follows in faces-config.xml:

<render-kit>
    <renderer>
        <component-family>org.primefaces.component</component-family>
        <renderer-type>org.primefaces.component.SelectManyCheckboxRenderer</renderer-type>
        <renderer-class>com.example.YourSelectManyCheckboxRenderer</renderer-class>
    </renderer>
</render-kit>

It might be worth the effort to post an enhancement request to PF guys to include the item description. It isn't been used anywhere in their UISelectOne/UISelectMany components.

回答2:

I had to modify BalusC's solution to make it work in my case. That is beacause I had to build the List of SelectItems on the Bean-side.

public List<SelectItem> getMyItems(){
  List<SelectItem> mySelectItems = new ArrayList<>();
  [loop or ohter code to collect items]
  // create SelectItem with description
  mySelectItems.add(new SelectItem([value], [label], [description]));
  ...
  return mySelectItems;
}

Then these SelectItems can be used with:

<f:selectItems value="#{myBean.myItems}"/>