dart - 父级分离回调中的children.clear期间的附加回调

Question

简单场景:有 2 个 Web 组件，父级中的子级。
当将父级重新插入到其他地方时，分离 已调用父级的回调，并在其中调用 children.clear() (也许这里是愚蠢的地方)。
在清理 child 的过程中，我可以看到不仅 child 的分离 cb 调用了，但是 附也:

https://dartpad.dartlang.org/26921310fb7f85dee672

import 'dart:html';

void main() {

  document.registerElement("x-my", MyElement);
  document.registerElement("x-ch", MyChild);
  var container = new Element.tag("x-my");
  document.body.children.add( container );
  print("creation done");

  // just re-add container to somewhere else
  var anothercontainer = new Element.div();
  document.body.children.add( anothercontainer );
  anothercontainer.children.add(container);

}

class MyElement extends HtmlElement {
  MyElement.created() : super.created();

  @override
  attached() {
    print("attached enter ${this.outerHtml}");
    super.attached();
    children.add( new Element.tag("x-ch") );
    print("attached leave ${this.outerHtml}");
  }

   @override
  detached() {
    print("detached enter ${this.outerHtml}");
    children.clear();
    super.detached();
    print("detached leave ${this.outerHtml}");
  }
}

class MyChild extends HtmlElement {
  MyChild.created() : super.created() { this.innerHtml = "child created"; }

  @override
  attached() {
    print("attached enter ${this.outerHtml}");
    super.attached();
    print("attached leave ${this.outerHtml}");
  }

   @override
  detached() {
    print("detached enter ${this.outerHtml}");
    super.detached();
    print("detached leave ${this.outerHtml}");
  }
}

给出输出:

attached enter <x-my></x-my>
attached enter <x-ch>child created</x-ch>
attached leave <x-ch>child created</x-ch>
attached leave <x-my><x-ch>child created</x-ch></x-my>
creation done
detached enter <x-my><x-ch>child created</x-ch></x-my>
detached enter <x-ch>child created</x-ch>
detached leave <x-ch>child created</x-ch>
attached enter <x-ch>child created</x-ch> <---- my question
attached leave <x-ch>child created</x-ch>
detached enter <x-ch>child created</x-ch>
detached leave <x-ch>child created</x-ch> <---- ends here
detached leave <x-my></x-my>
attached enter <x-my></x-my>
attached enter <x-ch>child created</x-ch>
attached leave <x-ch>child created</x-ch>
attached leave <x-my><x-ch>child created</x-ch></x-my>

Answer 1

关于这个 AFAIR 有一个 Unresolved 问题。我认为这是由于从自定义元素的构造函数中修改 DOM 造成的。

尝试移动

 this.innerHtml = "child created";

至attached()