Tapestry checkbox turned into a String ("TRUE" AND "FALSE")

I work with Tapestry 5.3 right now, and I try to use for my checkbox value. Well, the result is, the checkbox field now turned into a text (showing "true" and "false"), and not as a checkbox as usual.

So, my checkbox is in my loop, and my loop is in my grid, both my grid and loop using the same source. BTW, I don't use encoder in my loop. Is it fine anyway? Thanks for help.

<t:grid id="detailTable" class="t-data-grid draggable" source="details" row="detail">
   <t:loop source="details" value="detail">
      <p:featureCell> ${detail.feature}
      </p:featureCell>
      <p:enableCreateCell>
          <t:label for="createCheckbox"</t:label>
          <t:checkbox t:id="createCheckbox t"value="detail.enableCreate />
      </p:enableCreateCell>
      <p:enableReadCell>
          <t:label for="readCheckbox"</t:label>
          <t:checkbox t:id="readCheckbox t"value="detail.enableRead />
      </p:enableReadCell>
   </t:loop>
</t:grid>