private void Button_Click_1(object sender, RoutedEventArgs e)
        {
            List <string> Queries = new List <string>();

            // for each of the following queries there should be a case in the switch below
            Queries.Add("Children who don't have a single contract");
            Queries.Add("Nannies who get their vacation from the minister of economy");
            Queries.Add("Contracts in which the children met the nanny");
            Queries.Add("Contracts that are signed");
            Queries.Add("Mothers for which there is no nanny that can fit 100% with their schedule");
            ListDisplay listDisplay;
            // note that the constructor below has a quite long parameter
            ChoicePromptWin choicePromptWin = new ChoicePromptWin(Queries, "What do you wish to find?", (s) =>
            {
                switch ((string)s)
                { // a case for each of the queries above
                case "Children who don't have a single contract":
                    listDisplay = new ListDisplay((string)s, "Go to selected child's window", bl.UnattendedChildren());
                    listDisplay.ShowDialog();
                    break;

                case "Nannies who get their vacation from the minister of economy":
                    listDisplay = new ListDisplay((string)s, "Go to selected nanny's window", bl.VacationByEconomy());
                    listDisplay.ShowDialog();
                    break;

                case "Contracts in which the children met the nanny":
                    listDisplay = new ListDisplay((string)s, "Go to selected contract's window", bl.ContractsByCondition(c => c.IsMet));
                    listDisplay.ShowDialog();
                    break;

                case "Contracts that are signed":
                    listDisplay = new ListDisplay((string)s, "Go to selected contract's window", bl.ContractsByCondition(c => c.IsSigned));
                    listDisplay.ShowDialog();
                    break;

                case "Mothers for which there is no nanny that can fit 100% with their schedule":
                    listDisplay = new ListDisplay((string)s, "Go to selected mother's window", from Mother m in bl.GetMothers() where bl.SuitableNannies(m).Count() == 0 select m);
                    listDisplay.ShowDialog();
                    break;
                }
            }); // This is the end of the constructor above

            choicePromptWin.ShowDialog();
            ///////////////////////////////////////////////////////////////////////// OLD***********************OLD
            //string ret = "Nannies with vaction from the minister of economy:\n";
            //foreach (Nanny n in bl.VacationByEconomy())
            //    ret += bl.ToShortString(n) + "\n";
            //ret += "**************\nUnattended Children:\n";
            //foreach (Child c in bl.UnattendedChildren())
            //    ret += bl.ToShortString(c) +"\n";
            //ret += "***************\nContracts where children met the nanny:\n";
            //foreach (Contract c in bl.ContractsByCondition(c => c.IsMet))
            //    ret += bl.ToShortString(c) + "\n";
            //ret += "***************\nNumber of signed contracts:" + bl.NumOfContractsByCondition(c => c.IsSigned);
            //MessageBox.Show(ret);
        }
        private void ShowChildBTN_Click(object sender, RoutedEventArgs e)
        {
            //if (ChildLST.SelectedItem == null)
            //{
            //    MessageBox.Show("Please select a child first");
            //    return;
            //}
            //string id = "";
            //for (int i = 0; i < ChildLST.SelectedItem.ToString().Length && ChildLST.SelectedItem.ToString()[i] != ' '; i++)
            //    id += ChildLST.SelectedItem.ToString()[i];
            //Child c = bl.FindChildByID(id);
            //ShowObjectWin showObjectWin = new ShowObjectWin(c);
            //showObjectWin.ShowDialog();
            ListDisplay listDisplay = new ListDisplay("List of all children", "Go to selected child's window", bl.GetChildren());

            listDisplay.ShowDialog();
        }
        private void ShowMotherBTN_Click(object sender, RoutedEventArgs e)
        {
            //if (MotherLST.SelectedItem == null)
            //{
            //    MessageBox.Show("Please select a mother first");
            //    return;
            //}
            //string id = "";
            //for (int i = 0; i < MotherLST.SelectedItem.ToString().Length && MotherLST.SelectedItem.ToString()[i] != ' '; i++)
            //    id += MotherLST.SelectedItem.ToString()[i];
            //Mother m = bl.FindMotherByID(id);
            //ShowObjectWin showObjectWin = new ShowObjectWin(m);
            //showObjectWin.ShowDialog();
            ListDisplay listDisplay = new ListDisplay("List of all mothers", "Go to selected mother's window", bl.GetMothers());

            listDisplay.ShowDialog();
        }
        private void ShowNannyBTN_Click(object sender, RoutedEventArgs e)
        {
            //if (NannyLST.SelectedItem == null)
            //{
            //    MessageBox.Show("Please select a nanny first");
            //    return;
            //}
            //string id = "";
            //for (int i = 0; i < NannyLST.SelectedItem.ToString().Length && NannyLST.SelectedItem.ToString()[i] != ' '; i++)
            //    id += NannyLST.SelectedItem.ToString()[i];
            //Nanny n = bl.FindNannyByID(id);
            //ShowObjectWin showObjectWin = new ShowObjectWin(n);
            //showObjectWin.ShowDialog();
            ListDisplay listDisplay = new ListDisplay("List of all nannies", "Go to selected nanny's window", bl.GetNannies());

            listDisplay.ShowDialog();
        }
        private void ShowContractBTN_Click(object sender, RoutedEventArgs e)
        {
            //if (ContractLST.SelectedItem == null)
            //{
            //    MessageBox.Show("Please select a contract first");
            //    return;
            //}
            //string id = "";
            //for (int i = 0; i < ContractLST.SelectedItem.ToString().Length && ContractLST.SelectedItem.ToString()[i] != ' '; i++)
            //    id += ContractLST.SelectedItem.ToString()[i];
            //Contract c = bl.FindContractBySerialNum(id);
            //ShowObjectWin showObjectWin = new ShowObjectWin(c);
            //showObjectWin.ShowDialog();
            ListDisplay listDisplay = new ListDisplay("List of all contracts", "Go to selected contract's window", bl.GetContracts());

            listDisplay.ShowDialog();
        }