private void OnChildRemoved(TreeGridElement child)
{
// Clear the model for the child
child.SetModel(null);
// Notify the model that a child was removed from the item
Model?.OnChildRemoved(child);
}
private void OnChildAdded(object item)
{
// Verify the new child
TreeGridElement child = VerifyItem(item);
// Set the model for the child
child.SetModel(Model, this);
// Notify the model that a child was added to the item
Model?.OnChildAdded(child);
}
private void OnChildReplaced(TreeGridElement oldChild, object item, int index)
{
// Verify the new child
TreeGridElement child = VerifyItem(item);
// Clear the model for the old child
oldChild.SetModel(null);
// Notify the model that a child was replaced
Model?.OnChildReplaced(oldChild, child, index);
}
internal void SetModel(TreeGridModel model, TreeGridElement parent = null)
{
// Set the element information
Model = model;
Parent = parent;
Level = ((parent != null) ? parent.Level + 1 : 0);
// Iterate through all child elements
foreach (TreeGridElement child in Children)
{
// Set the model for the child
child.SetModel(model, this);
}
}
private void OnIsExpandedChanged(TreeGridElement element, AvaloniaPropertyChangedEventArgs args)
{
TreeGridElement item = element;
// Is the item being expanded?
if ((bool)args.NewValue)
{
// Raise expanding event
item.RaiseEvent(new RoutedEventArgs(ExpandingEvent, item));
// Execute derived expanding handler
item.OnExpanding();
// Expand the item in the model
item.Model?.Expand(item);
// Raise expanded event
item.RaiseEvent(new RoutedEventArgs(ExpandedEvent, item));
// Execute derived expanded handler
item.OnExpanded();
}
else
{
// Raise collapsing event
item.RaiseEvent(new RoutedEventArgs(CollapsingEvent, item));
// Execute derived collapsing handler
item.OnCollapsing();
// Collapse the item in the model
item.Model?.Collapse(item);
// Raise collapsed event
item.RaiseEvent(new RoutedEventArgs(CollapsedEvent, item));
// Execute derived collapsed handler
item.OnCollapsed();
}
}