private void buttonAdd_Click(object sender, RoutedEventArgs e)
 {
     if (IsNotEmpty(textBoxWEP_Name) & IsNotEmpty(textBoxWEP_Surname))
     {
         var currentFootballer = new Footballer(textBoxWEP_Name.Text.Trim(), textBoxWEP_Surname.Text.Trim(), (uint)sliderAge.Value, (uint)sliderWeight.Value);
         var onList            = false;
         foreach (var p in listBoxFootballer.Items)
         {
             var fballer = p as Footballer;
             if (fballer.isTheSame(currentFootballer))
             {
                 onList = true;
                 break;
             }
         }
         if (!onList)
         {
             listBoxFootballer.Items.Add(currentFootballer);
             Clear();
         }
         else
         {
             var dialog = MessageBox.Show($"{currentFootballer.ToString()} już jest na liście {Environment.NewLine} Czy wyczyścić formularz?", "Uwaga", MessageBoxButton.OKCancel);
             if (dialog == MessageBoxResult.OK)
             {
                 Clear();
             }
         }
     }
 }
        private void buttonDelete_Click(object sender, RoutedEventArgs e)
        {
            var currentFootballer = new Footballer(textBoxWEP_Name.Text.Trim(), textBoxWEP_Surname.Text.Trim(), (uint)sliderAge.Value, (uint)sliderWeight.Value);
            var dialog            = MessageBox.Show($"Czy na pewno chcesz usunąć {currentFootballer.ToString()} z listy?", "Uwaga", MessageBoxButton.OKCancel);

            if (dialog == MessageBoxResult.OK)
            {
                listBoxFootballer.Items.Remove(listBoxFootballer.SelectedItem);
                Clear();
            }
        }
        private void buttonEdit_Click(object sender, RoutedEventArgs e)
        {
            if (IsNotEmpty(textBoxWEP_Name) & IsNotEmpty(textBoxWEP_Surname))
            {
                var currentFootballer = new Footballer(textBoxWEP_Name.Text.Trim(), textBoxWEP_Surname.Text.Trim(), (uint)sliderAge.Value, (uint)sliderWeight.Value);
                var onList            = false;
                foreach (var p in listBoxFootballer.Items)
                {
                    var fballer = p as Footballer;
                    if (fballer.isTheSame(currentFootballer))
                    {
                        onList = true;
                        break;
                    }
                }
                if (!onList)
                {
                    var dialogResult = MessageBox.Show($"Czy na pewno chcesz zmienić dane  {Environment.NewLine} {listBoxFootballer.SelectedItem}?", "Edycja", MessageBoxButton.YesNo);

                    if (dialogResult == MessageBoxResult.Yes)
                    {
                        var selectedFootballer = (Footballer)listBoxFootballer.SelectedItem;
                        selectedFootballer.Name    = currentFootballer.Name;
                        selectedFootballer.Surname = currentFootballer.Surname;
                        selectedFootballer.Age     = currentFootballer.Age;
                        selectedFootballer.Weight  = currentFootballer.Weight;
                        listBoxFootballer.Items.Refresh();
                    }
                    Clear();
                    listBoxFootballer.SelectedIndex = -1;
                }
                else
                {
                    MessageBox.Show($"{currentFootballer.ToString()} już jest na liście.", "Uwaga");
                }
            }
        }