TreeExpandableItemsHandler.java 文件源码

@Override
protected Pair<Component, Rectangle> getCellRendererAndBounds(Integer key) {
  int rowIndex = key.intValue();

  TreePath path = myComponent.getPathForRow(rowIndex);
  if (path == null) return null;

  Rectangle bounds = myComponent.getPathBounds(path);
  if (bounds == null) return null;

  TreeCellRenderer renderer = myComponent.getCellRenderer();
  if (renderer == null) return null;

  Object node = path.getLastPathComponent();
  Component rendererComponent = renderer.getTreeCellRendererComponent(
    myComponent,
    node,
    myComponent.isRowSelected(rowIndex),
    myComponent.isExpanded(rowIndex),
    myComponent.getModel().isLeaf(node),
    rowIndex,
    myComponent.hasFocus()
  );
  return Pair.create(rendererComponent, bounds);
}