| 摘要 |
<p>Various technologies and techniques are disclosed for managing layout updates to user interface elements. A dirty state of user interface elements is tracked in a tree with multiple nodes of user interface elements. The dirty state allows dirty subtrees of the nodes to be identified. A root node is identified for each of the dirty subtrees. Affected portions of the tree are updated, starting with the root node that was identified for each of the dirty subtrees. As part of the update process, changes to ancestor nodes are detected and used to make a layout process more efficient. For example, any layout processes that are currently being performed on any descendant nodes of a changed ancestor are abandoned, and the layout process is resumed at the changed ancestor. After updating affected portions of the tree, the updated user interface elements are then rendered on an output device.</p> |
