private void SetStateForChildren(CheckableTreeItem item, bool?state)
{
foreach (var child in item.Children)
{
child.IsChecked = state;
SetStateForChildren(child, state);
}
}
public static IEnumerable <CheckableTreeItem> GetChildSelectedItems(CheckableTreeItem treeItem)
{
var childSelectedItems = new List <CheckableTreeItem>();
foreach (var checkableTreeItem in treeItem.Children.Where(item => !item.IsChecked.HasValue || item.IsChecked.Value))
{
childSelectedItems.Add(checkableTreeItem);
childSelectedItems.AddRange(GetChildSelectedItems(checkableTreeItem));
}
return(childSelectedItems);
}
private void UpdateParentState(CheckableTreeItem item)
{
if (item.ParentItem == null)
{
return;
}
bool?parentState = item.IsChecked;
if (item.ParentItem.Children.Any(child => parentState != child.IsChecked))
{
parentState = null;
}
item.ParentItem.IsChecked = parentState;
// update next parent state
UpdateParentState(item.ParentItem);
}
private TreeViewItem BuildTreeViewItem(CheckableTreeItem treeItem)
{
// create header with checkBox
var header = new CheckBox()
{
Content = treeItem.Description,
IsThreeState = false,
Margin = new Thickness(2)
};
BindingOperations.SetBinding(header, System.Windows.Controls.CheckBox.IsCheckedProperty, new Binding("IsChecked")
{
UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged,
Mode = BindingMode.TwoWay,
NotifyOnTargetUpdated = true
});
header.Click += (sender, args) =>
{
SetStateForChildren(treeItem, header.IsChecked);
UpdateParentState(treeItem);
selectionChanged = true;
// update commands
(SaveCommand as Command).ValidateCanExecute();
};
// create main item
var treeViewItem = new TreeViewItem()
{
DataContext = treeItem,
Header = header,
IsExpanded = true
};
// add child items
foreach (var childTreeItem in treeItem.Children)
{
treeViewItem.Items.Add(BuildTreeViewItem(childTreeItem));
}
return(treeViewItem);
}