private void ButtonRemoveSource_Click(object sender, EventArgs e) { if (!_machineAvailable) { return; } if (listViewSources.SelectedItems.Count == 0) { return; } _selectedSource = (DistributionSource)listViewSources.SelectedItems[0].Tag; DistributionSources.Remove(_selectedSource); DistributionSourcesChanged = true; listViewSources.Items.Remove(listViewSources.SelectedItems[0]); _selectedSource = null; EnableControls(); }