Whats the fieldname for “Tot of landed”? … it was no mentioned before. Is ‘custom_landed’? Is there any other field in the parent doctype to update? I don’t fully understand what are you trying to achieve …
frappe.ui.form.on('Material Request', {
refresh: function(frm) {
var total_value = 0.0;
var items = frm.doc.items;
for (var i = 0; i < items.length; i++) {
var row = items[i];
var qty = row['qty'] || 0; // Handle potential undefined values
var rate = row['custom_landed_cost'] || 0; // Handle potential undefined values
total_value += (qty * rate);
frappe.model.set_value("Material Request Item", row['name'], "custom_tot_of_landed", qty*rate)
}
// frm.set_value('custom_landed', total_value);
}
});
Anyway, maybe is better use client script for child doctype, and triggering tot_of_landed after qty or rate change. This will work: