public static void CloneTree(
VisualTreeAsset vta, VisualElement target,
Dictionary <string, VisualElement> slotInsertionPoints,
List <TemplateAsset.AttributeOverride> attributeOverrides)
{
if (target == null)
{
throw new ArgumentNullException(nameof(target));
}
if ((vta.visualElementAssets == null || vta.visualElementAssets.Count <= 0) &&
(vta.templateAssets == null || vta.templateAssets.Count <= 0))
{
return;
}
var idToChildren = VisualTreeAssetUtilities.GenerateIdToChildren(vta);
List <VisualElementAsset> rootAssets;
// Tree root has parentId == 0
idToChildren.TryGetValue(0, out rootAssets);
if (rootAssets == null || rootAssets.Count == 0)
{
return;
}
#if !UNITY_2019_4
var uxmlRootAsset = rootAssets[0];
vta.AssignClassListFromAssetToElement(uxmlRootAsset, target);
vta.AssignStyleSheetFromAssetToElement(uxmlRootAsset, target);
// Get the first-level elements. These will be instantiated and added to target.
idToChildren.TryGetValue(uxmlRootAsset.id, out rootAssets);
if (rootAssets == null || rootAssets.Count == 0)
{
return;
}
#endif
rootAssets.Sort(VisualTreeAssetUtilities.CompareForOrder);
foreach (VisualElementAsset rootElement in rootAssets)
{
Assert.IsNotNull(rootElement);
// Don't try to instatiate the special selection tracking element.
if (rootElement.fullTypeName == BuilderConstants.SelectedVisualTreeAssetSpecialElementTypeName)
{
continue;
}
VisualElement rootVe = CloneSetupRecursively(vta, rootElement, idToChildren,
new CreationContext(slotInsertionPoints, attributeOverrides, vta, target));
// if contentContainer == this, the shadow and the logical hierarchy are identical
// otherwise, if there is a CC, we want to insert in the shadow
target.hierarchy.Add(rootVe);
}
}