ZK How to sort a listbox with multiple components in a listcell

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In below listbox, i have listcell that contains both "Select" and "Label" component. Hence even the listheader applied sort="auto", it not actually worked. Anyone can help to figure out a way so the listcell can be sorted, thanks a lot

<listbox id="idResultListBox" checkmark="true" vflex="1"  >
                    <listhead>
                        <listheader
                            label="${ labels.result.result }" sort="auto"/>
                        <listheader
                            label="${ labels.result.resultEnteredBy }" sort="auto"/>
                        <listheader
                            label="${ labels.result.resultEnteredOn }" sort="auto"/>
                        <listheader
                            label="${ labels.result.resultAuditedBy }" sort="auto"/>
                    </listhead>
                    <listitem 
                        forEach="${attAuditResultList }"
                        value="${each }"
                        disabled="${ displayMode!='view' and each.auditedDate!=null }"
                        checkable="${ each.auditedDate==null }">
                        <listcell>
                            <select value="${ each.result }" options="${ resultTypeList }"
                                if="${ each.auditedDate==null }" visible="${ each.auditedDate==null and displayMode!='view' }"
                                 />
                            <label value="${ each.result.name }"
                                visible="${ each.auditedDate!=null or displayMode=='view' }" forward="/>
                        </listcell>
                        <listcell>
                            <activeassessor if="${ each.auditedDate==null }" value="${ each.enteredBy }"
                                 />
                            <label value="${ each.enteredBy.name }"
                                visible="${ each.auditedDate!=null }" />
                        </listcell>
                        <listcell
                            label="${ each.enteredDateAsString }" />
                        <listcell label="${ each.auditedBy.name }" />>
                    </listitem>
                </listbox>