/// <summary>
/// Insert an element into this element's contentContainer
/// </summary>
public void Insert(int index, VisualElement child)
{
if (child == null)
{
throw new ArgumentException("Cannot insert null child");
}
if (index > childCount)
{
throw new ArgumentOutOfRangeException("Index out of range: " + index);
}
if (child == m_Owner)
{
throw new ArgumentException("Cannot insert element as its own child");
}
if (m_Owner.elementPanel != null && m_Owner.elementPanel.duringLayoutPhase)
{
throw new InvalidOperationException(k_InvalidHierarchyChangeMsg);
}
child.RemoveFromHierarchy();
if (ReferenceEquals(m_Owner.m_Children, s_EmptyList))
{
//TODO: Trigger a release on finalizer or something, this means we'll need to make the pool thread-safe as well
m_Owner.m_Children = VisualElementListPool.Get();
}
if (m_Owner.yogaNode.IsMeasureDefined)
{
m_Owner.RemoveMeasureFunction();
}
PutChildAtIndex(child, index);
int imguiContainerCount = child.imguiContainerDescendantCount + (child.isIMGUIContainer ? 1 : 0);
if (imguiContainerCount > 0)
{
m_Owner.ChangeIMGUIContainerCount(imguiContainerCount);
}
child.hierarchy.SetParent(m_Owner);
child.PropagateEnabledToChildren(m_Owner.enabledInHierarchy);
child.InvokeHierarchyChanged(HierarchyChangeType.Add);
child.IncrementVersion(VersionChangeType.Hierarchy);
m_Owner.IncrementVersion(VersionChangeType.Hierarchy);
}
