noInside<T> static method

bool? Function(TreeNode<T> dragNode, TreeNode<T>? targetNode, DropPosition position) noInside<T>()

禁止拖拽到内部（只允许同级排序）

适用于不需要层级结构变化，只需要同级排序的场景

示例：

TolyDraggableTree(
  canDrop: DragRules.noInside<MyData>(),
  // ...
)

Implementation

static bool? Function(
        TreeNode<T> dragNode, TreeNode<T>? targetNode, DropPosition position)
    noInside<T>() {
  return (dragNode, targetNode, position) => position != DropPosition.inside;
}