private void Btn_set_Clicked(object sender, EventArgs e)
        {
            Stundenplan sp = new Stundenplan();

            sp.stunden[0, 0] = monday_1.Text;
            sp.stunden[0, 1] = monday_2.Text;
            sp.stunden[0, 2] = monday_3.Text;
            sp.stunden[0, 3] = monday_4.Text;
            sp.stunden[0, 4] = monday_5.Text;
            sp.stunden[0, 5] = monday_6.Text;
            sp.stunden[0, 6] = monday_7.Text;
            sp.stunden[0, 7] = monday_8.Text;

            sp.stunden[1, 0] = tuesday_1.Text;
            sp.stunden[1, 1] = tuesday_2.Text;
            sp.stunden[1, 2] = tuesday_3.Text;
            sp.stunden[1, 3] = tuesday_4.Text;
            sp.stunden[1, 4] = tuesday_5.Text;
            sp.stunden[1, 5] = tuesday_6.Text;
            sp.stunden[1, 6] = tuesday_7.Text;
            sp.stunden[1, 7] = tuesday_8.Text;

            sp.stunden[2, 0] = wednesday_1.Text;
            sp.stunden[2, 1] = wednesday_2.Text;
            sp.stunden[2, 2] = wednesday_3.Text;
            sp.stunden[2, 3] = wednesday_4.Text;
            sp.stunden[2, 4] = wednesday_5.Text;
            sp.stunden[2, 5] = wednesday_6.Text;
            sp.stunden[2, 6] = wednesday_7.Text;
            sp.stunden[2, 7] = wednesday_8.Text;

            sp.stunden[3, 0] = thursday_1.Text;
            sp.stunden[3, 1] = thursday_2.Text;
            sp.stunden[3, 2] = thursday_3.Text;
            sp.stunden[3, 3] = thursday_4.Text;
            sp.stunden[3, 4] = thursday_5.Text;
            sp.stunden[3, 5] = thursday_6.Text;
            sp.stunden[3, 6] = thursday_7.Text;
            sp.stunden[3, 7] = thursday_8.Text;

            sp.stunden[4, 0] = friday_1.Text;
            sp.stunden[4, 1] = friday_2.Text;
            sp.stunden[4, 2] = friday_3.Text;
            sp.stunden[4, 3] = friday_4.Text;
            sp.stunden[4, 4] = friday_5.Text;
            sp.stunden[4, 5] = friday_6.Text;
            sp.stunden[4, 6] = friday_7.Text;
            sp.stunden[4, 7] = friday_8.Text;


            switch (TCPCommandManager.SetStundenplan(JsonConvert.SerializeObject(sp)))
            {
            case 201:
                DisplayAlert("Erfolgreich", "Stundenplan konnte gespeichert", "OK");
                Navigation.PushAsync(new ControllPanel());
                Navigation.RemovePage(this);
                break;

            default:
                DisplayAlert("Fehler", "Stundenplan konnte nicht gesetzt werden", "OK");
                break;
            }
        }