private void button3_Click(object sender, EventArgs e)
        {
            AddEditKeysDialog d = new AddEditKeysDialog(Configuration, null);

            if (d.ShowDialog(this) == DialogResult.OK)
            {
                List <KeysInputVariable> keys = new List <KeysInputVariable>(Configuration.Keys);
                keys.Add(d.Key);
                Configuration.Keys = keys.ToArray();
                ShowKeys();
            }
        }
 private void button4_Click(object sender, EventArgs e)
 {
     if (listView1.SelectedItems.Count > 0)
     {
         KeysInputVariable k = listView1.SelectedItems[0].Tag as KeysInputVariable;
         if (k != null)
         {
             AddEditKeysDialog d = new AddEditKeysDialog(Configuration, k);
             if (d.ShowDialog(this) == DialogResult.OK)
             {
                 ShowKeys();
             }
         }
     }
 }