Sorting can be enable via the `sortable` attribute in the `<tc:column/>`. A custom sorting implementation can be set in the `sortActionListener` attribute in the `<tc:sheet/>`.

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In this example, the `sortable` attribute is 'true' for all columns. Notice, that there are negative periods.

    <tc:column label="Name" sortable="true">

All columns in this sheet can be sorted. A custom sorting implementation is set. Now, the sign for period numbers is ignored by sorting.

    <tc:sheet value="\#{sheetController.solarList}"
        var="solarobject" rows="4"
        sortActionListener="\#{sheetController.sheetSorter}">
          <tc:column id="namecol" label="Name" sortable="true">
          ...