// BUTTONS EVENT
        private void button_add_Click(object sender, EventArgs e)
        {
            // creating an array for receive the settings from the new form
            string[] allParams = null;

            // build listview group for sending it to the new form
            List <string> allGroup = new List <string>();

            foreach (ListViewGroup group in listView_filament.Groups)
            {
                allGroup.Add(group.Header);
            }

            // Open the new form
            using (addEdit_form OpenForm = new addEdit_form(host, allGroup))
            {
                OpenForm.ShowDialog();
                allParams = OpenForm.allParams;
            }
            if (allParams == null)
            {
                return;
            }

            // Creating the item and add into the listview
            createAddNewItem(allParams);

            // Save data in the registry
            saveRegistry();
        }
        private void button_edit_Click(object sender, EventArgs e)
        {
            // if no item selected in the listview return
            if (listView_filament.SelectedItems.Count == 0)
            {
                return;
            }

            // build listview group for sending it to the new form
            List <string> allGroup = new List <string>();

            foreach (ListViewGroup group in listView_filament.Groups)
            {
                allGroup.Add(group.Header);
            }

            // build an array with all settings, for sending it to the new form
            // 0: Name; 1:diameter; 2:ExMulti; 3:temp; 4:coust; 5:density; 6:note; 7:group
            string[] allParams = new string[8];
            allParams[0] = listView_filament.SelectedItems[0].SubItems[0].Text;
            allParams[1] = listView_filament.SelectedItems[0].SubItems[1].Text;
            allParams[2] = listView_filament.SelectedItems[0].SubItems[2].Text;
            allParams[3] = listView_filament.SelectedItems[0].SubItems[3].Text;
            allParams[4] = listView_filament.SelectedItems[0].SubItems[4].Text;
            allParams[5] = listView_filament.SelectedItems[0].SubItems[5].Text;
            allParams[6] = listView_filament.SelectedItems[0].SubItems[6].Text;
            allParams[7] = listView_filament.SelectedItems[0].Group.Header;


            // Open the new form with the item editor
            using (addEdit_form OpenForm = new addEdit_form(host, allGroup, allParams))
            {
                OpenForm.ShowDialog();
                //copy the new settings in the array
                allParams = OpenForm.allParams;
            }

            if (allParams == null)
            {
                return;
            }

            // remove the old item from listview and add a new item with new params
            listView_filament.BeginUpdate();
            listView_filament.Items.Remove(listView_filament.SelectedItems[0]);
            createAddNewItem(allParams);
            listView_filament.EndUpdate();

            // Save data in the registry
            saveRegistry();
        }