Uncaught TypeError: Cannot read property 'getSelectedItems' of undefined

Also , I believe you were trying to get selected rows from a table which is in the popup, and your snippet is not able to find that table component properly due to your action framework issues .

Try to use below sample code to get your table rows selected ,

var table = skuid.$(‘#MyTable’), list, selectedItems;  
//Here #MyTable - is table’s unique ID given in table properties

if (table.length)
{
   list = table.data(‘object’).list;
   selectedItems = list.getSelectedItems();
}

var idsArray = skuid.$.map(selectedItems ,function(item){ 
              return item.row.Id; 
});


Hope this helps!

For more details : https://community.skuid.com/t/getting-the-selected-records-on-a-table-without-using-mass-row-action-and-instead-using-a-button/1497