public void setLoaded(int index, boolean value) {
        if (!value) {
            getStateHelper().remove("loaded_" + index);
        }
        else {
            getStateHelper().put("loaded_" + index, value);
        }
    }
In case of a repeating parent (var=...), we need to store the state on row basis.
This is actually a workaround because neither UITabPanel, not UIRepeat has a rowStatePreserved attribute.

@param index The tab index.
@param value The loaded state.
primefaces/src/main/java/org/primefaces/component/tabview/Tab.java