在 Chrome 浏览器的地址字段中,输入 chrome://inspect#devices 以启动 Chrome 检查器。您应该会在页面上看到设备列表,并且画布 HTML 网址应该会列在测试用 Google Home 或 Google Nest 设备的名称下方。请注意,Chrome 可能需要一些时间才能发现您网络中的所有设备。
点击 HTML 网址下的 inspect 链接以启动 Chrome 开发者工具。
Chrome 开发者工具会在自己的窗口中加载。您可以点击抓屏 () 按钮来查看设备上呈现的网页 GUI。以下屏幕截图展示了您的 Web 应用在 Chrome 开发者工具中的显示方式:
[null,null,["最后更新时间 (UTC):2025-07-25。"],[[["\u003cp\u003eDebug your Interactive Canvas web app using Chrome DevTools on Google Home or Nest smart displays running supported software and firmware versions.\u003c/p\u003e\n"],["\u003cp\u003eSet up your environment by enabling your Action for testing, connecting devices to the same network, ensuring network connectivity, and using the same Google account.\u003c/p\u003e\n"],["\u003cp\u003eConnect to the debugger by launching Chrome Inspector, locating your device and Canvas HTML URL, and clicking "inspect" to open DevTools.\u003c/p\u003e\n"],["\u003cp\u003eUtilize debugging tips such as refreshing the DevTools page, checking for JavaScript errors, adding breakpoints, and monitoring performance and memory usage.\u003c/p\u003e\n"],["\u003cp\u003eThird-party smart display devices are not supported for debugging Canvas web apps.\u003c/p\u003e\n"]]],[],null,["# Debug your Interactive Canvas web app with Chrome DevTools\n\nYou can debug your Interactive Canvas web app using [Chrome DevTools](https://developers.google.com/web/tools/chrome-devtools). The Chrome debugger\nis supported on Google Home or Google Nest smart displays with a software\nversion of 30 or later (this update starts rolling out in October 2020)\nand a Cast firmware version of 1.50 or later. You can\ncheck the versions under `System settings / About device` on your smart display.\n| **Note:** Debugging Canvas web apps on third-party smart display devices is not supported.\n\nSet up your environment\n-----------------------\n\nBefore you can debug, do the following to set up your environment correctly:\n\n- Enable your Action for testing in the Actions console [simulator](/assistant/conversational/build/projects#test_projects_in_the_simulator).\n- Connect your machine to the same local area network as the Google Home or Google Nest device you are testing.\n- Ensure that your network doesn't block packets between devices.\n- Log in with the same Google account on the Actions console and on the Google Home or Google Nest device.\n\nOnce your environment is ready, you can launch your Action on your test\nsmart display.\n| **Note:** You cannot debug your Canvas web app until you've launched your development Action on your test smart display.\n\nConnect Canvas web app to debugger\n----------------------------------\n\nTo connect your Canvas web app to the Chrome DevTools debugger, follow these\nsteps:\n\n1. In your local development machine, install and launch the [Google Chrome browser](https://www.google.com/chrome/).\n2. In the address field of your Chrome browser, enter `chrome://inspect#devices` to launch the Chrome inspector. You should see a list of devices on the page, and the Canvas HTML URL should be listed under the name of your test Google Home or Google Nest device. Note that it might take some time for Chrome to discover all the devices on your network.\n3. Click the `inspect` link under the HTML URL to launch Chrome DevTools.\n\nChrome DevTools loads in its own window. You can click the screencast\n()\nbutton to see the web GUI rendered on the device. The following screenshot shows\nhow your web app appears in Chrome DevTools:\n\nNote that your Canvas web app is loaded in an iframe.\n\nDebugging tips\n--------------\n\nKeep the following additional tips in mind during debugging:\n\n- Refresh the page in Chrome DevTools to reload your local fulfillment app container with the latest code from your development URL.\n- Check that your JavaScript app loads without errors. To do this, check the console section of the DevTools page.\n- Add manual breakpoints to your code by using `debugger;` within your web app code.\n- If you don't see your device in the `chrome://inspect#devices` for an extended period of time, refresh the inspect page.\n- To debug any performance issues, follow the [Get Started with Analyzing Runtime Performance tutorial](https://developers.google.com/web/tools/chrome-devtools/evaluate-performance).\n- Because the smart display memory is limited, your web app might crash or hang if it goes over 200MB. To debug any memory issues, follow the [Fix Memory Problems tutorial](https://developers.google.com/web/tools/chrome-devtools/memory-problems).\n- For any fulfillment errors, look at requests sent by Actions on Google servers to the webhook from your webhook logs or from Stackdriver logs."]]