private void RecommendedModsToggleCheckbox_CheckedChanged(object sender, EventArgs e) { var state = ((CheckBox)sender).Checked; RecommendedModsListView.BeginUpdate(); foreach (ListViewItem item in RecommendedModsListView.Items) { if (item.Checked != state) { item.Checked = state; } } RecommendedModsListView.EndUpdate(); }