Jupyter Lab中ipywidgets Tab组件渲染异常求助
问题背景
ipywidgets的滑块等组件渲染正常，但Tab组件标题无法横向排列（标题存在且可点击），运行环境未激活虚拟环境但处于虚拟环境下级目录，使用的是官方示例代码：
import ipywidgets as widgets tab_contents = ['P0', 'P1', 'P2', 'P3', 'P4'] children = [widgets.Text(description=name) for name in tab_contents] tab = widgets.Tab() tab.children = children tab.titles = [str(i) for i in range(len(children))] tab
已尝试的操作：
- 更新Jupyter Lab和ipywidgets
- 重启电脑与Notebook
- 手动启用nbextension：
PS C:\Users\lee\PycharmProjects\htmlsandbox\wsj_econ> jupyter nbextension enable --py widgetsnbextension Enabling notebook extension jupyter-js-widgets/extension... - Validating: ok
关闭服务器时的错误日志：
[IPKernelApp] ERROR | No such comm target registered: jupyter.widget.control
[IPKernelApp] WARNING | No such comm: b4acacde-dc4d-4362-8768-8dad75ac0bba
[W 2023-06-21 18:24:05.684 ServerApp] Got events for closed stream <zmq.eventloop.zmqstream.ZMQStream object at 0x0000024A7BC79B40>
[W 2023-06-21 18:24:05.684 ServerApp] Got events for closed stream <zmq.eventloop.zmqstream.ZMQStream object at 0x0000024A7BE06260>
[E 2023-06-21 18:24:09.215 ServerApp] Uncaught exception GET /lab/api/extensions?query&page=1&per_page=30&refresh=0&1687386245224 (::1)
HTTPServerRequest(protocol='http', host='localhost:8888', method='GET', uri='/lab/api/extensions?query&page=1&per_page=30&refresh=0&1687386245224', version='HTTP/1.1', remote_ip='::1')
Traceback (most recent call last):
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\tornado\web.py", line 1713, in _execute
result = await result
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\jupyterlab\handlers\extension_manager_handler.py", line 37, in get
extensions, last_page = await self.manager.list_extensions(query, page, per_page)
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\jupyterlab\extensions\manager.py", line 368, in list_extensions
await self.refresh(query, page, per_page)
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\jupyterlab\extensions\manager.py", line 402, in refresh
await self._update_extensions_list(query, page, per_page)
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\jupyterlab\extensions\manager.py", line 575, in _update_extensions_list
extensions, last_page = await self.list_packages(query, page, per_page)
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\jupyterlab\extensions\pypi.py", line 214, in list_packages
data = await self.fetch_package_metadata(name, latest_version, self.base_url)
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\async_lru_init.py", line 218, in call
return await asyncio.shield(fut)
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\jupyterlab\extensions\pypi.py", line 36, in _fetch_package_metadata
response = await http_client.fetch(
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\tornado\simple_httpclient.py", line 340, in run
stream = await self.tcp_client.connect(
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\tornado\tcpclient.py", line 288, in connect
stream = await stream.start_tls(
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\tornado\iostream.py", line 1389, in _do_ssl_handshake
self.socket.do_handshake()
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\ssl.py", line 1342, in do_handshake
self._sslobj.do_handshake()
ConnectionResetError: [WinError 10054] An existing connection was forcibly closed by the remote host
[W 2023-06-21 18:24:09.253 ServerApp] wrote error: 'Unhandled error'
Traceback (most recent call last):
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\tornado\web.py", line 1713, in _execute
result = await result
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\jupyterlab\handlers\extension_manager_handler.py", line 37, in get
extensions, last_page = await self.manager.list_extensions(query, page, per_page)
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\jupyterlab\extensions\manager.py", line 368, in list_extensions
await self.refresh(query, page, per_page)
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\jupyterlab\extensions\manager.py", line 402, in refresh
await self._update_extensions_list(query, page, per_page)
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\jupyterlab\extensions\manager.py", line 575, in _update_extensions_list
extensions, last_page = await self.list_packages(query, page, per_page)
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\jupyterlab\extensions\pypi.py", line 214, in list_packages
data = await self.fetch_package_metadata(name, latest_version, self.base_url)
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\async_lru_init.py", line 218, in call
return await asyncio.shield(fut)
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\jupyterlab\extensions\pypi.py", line 36, in _fetch_package_metadata
response = await http_client.fetch(
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\tornado\simple_httpclient.py", line 340, in run
stream = await self.tcp_client.connect(
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\tornado\tcpclient.py", line 288, in connect
stream = await stream.start_tls(
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\site-packages\tornado\iostream.py", line 1389, in _do_ssl_handshake
self.socket.do_handshake()
File "C:\Users\lee\AppData\Local\Programs\Python\Python310\lib\ssl.py", line 1342, in do_handshake
self._sslobj.do_handshake()
ConnectionResetError: [WinError 10054] An existing connection was forcibly closed by the remote host
[E 2023-06-21 18:24:09.255 ServerApp] {
"Host": "localhost:8888",
"Accept": "/",
"Referer": "http://localhost:8888/lab",
"User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36"
}
解决方案
激活对应的虚拟环境
进入虚拟环境下级目录但未激活环境，会导致Jupyter调用全局环境的依赖，和虚拟环境中的ipywidgets版本不匹配，引发渲染异常。执行虚拟环境的激活命令（比如conda或venv的activate脚本），再启动Jupyter Lab。重新安装Jupyter Lab的ipywidgets扩展
Jupyter Lab 4.x版本需要安装对应的labextension，之前仅启用nbextension不够，执行以下命令（激活虚拟环境后）：pip install ipywidgets jupyter labextension install @jupyter-widgets/jupyterlab-manager若使用conda环境，也可以用
conda install -c conda-forge ipywidgets jupyterlab确保依赖一致。清理缓存并重启
执行jupyter lab clean清理Lab的缓存，然后重启Jupyter Lab，确保扩展加载生效。处理日志中的连接错误
日志中的ConnectionResetError是Lab尝试连接PyPI获取扩展信息时的网络问题，和Tab渲染无关，可忽略或检查网络代理设置，但不影响核心功能修复。
内容的提问来源于stack exchange，提问作者leeprevost
