Web script extension controller to add additional action(s) to data list items

actions-common.get.html.ftl

<@link rel="stylesheet" type="text/css" href="${url.context}/res/myco/components/data-lists/sample-action.css" group="datalists" />
<@script type="text/javascript" src="${url.context}/res/myco/components/data-lists/sample-action.js" group="datalists"></@script>

datagrid.get.js

if (model.widgets)
{
   for (var i = 0; i < model.widgets.length; i++)
   {
      var widget = model.widgets[i];
      if (widget.id == "DataGrid")
      {
         // These two lines only needed if you want to show the action in the 'actions' cell,
         // otherwise a 'More actions' menu will be created to display it.
         widget.options.splitActionsAt = 4;
         widget.options.actionsColumnWidth = 105; // splitActionsAt * 25 + 5
         // Add the action definition - this will be action-specific
         model.actionSet.push({
            id: "onActionSample", // Change to match your handler function name
            type: "action-link",
            permission: "",
            href: "",
            label: "actions.datalist.mycustom" // Change to match your custom label in datagrid.get.properties
         });
      }
   }
}

datagrid.get.properties

# Custom action labels
actions.datalist.sample=My Sample Action
actions.datalist.sample.message=It works!