// Verify that a calendar has been selected.
if (cmbCalendar->GetSelection() == -1 && editMode == false){
wxMessageBox("Please select a calendar for this entry.", "No calendar selected", wxOK);
// Verify that a calendar has been selected.
if (cmbCalendar->GetSelection() == -1 && editMode == false){
wxMessageBox("Please select a calendar for this entry.", "No calendar selected", wxOK);
if (txtEventName->GetValue().IsEmpty()){
wxMessageBox("The event name cannot be left empty.", "Event name is empty", wxOK);
if (txtEventName->GetValue().IsEmpty()){
wxMessageBox("The event name cannot be left empty.", "Event name is empty", wxOK);