/// <summary>
        /// Opening a new edit AddEditComputerWindow.
        /// </summary>
        private void BtnAdd_Click(object sender, RoutedEventArgs e)
        {
            AddEditComputerWindow addEditComputerWindow = new AddEditComputerWindow()
            {
                Tag = null
            };

            addEditComputerWindow.Closing += AddEditComputerWindow_Closing;
            addEditComputerWindow.ShowDialog();
        }
        /// <summary>
        /// Opening a new edit AddEditComputerWindow.
        /// </summary>
        private void BtnEdit_Click(object sender, RoutedEventArgs e)
        {
            AddEditComputerWindow addEditComputerWindow = new AddEditComputerWindow()
            {
                Tag = (Computer)this.dgManagement.SelectedItem
            };

            addEditComputerWindow.Closing += AddEditComputerWindow_Closing;
            addEditComputerWindow.ShowDialog();
        }