[null,null,["最后更新时间 (UTC):2025-07-25。"],[],[],null,["# Interface Subscribable\n\n| **Developer Preview:** Available as part of the [Google Workspace Developer Preview Program](https://developers.google.com/workspace/preview), which grants early access to certain features. \n|\n| **To use the Meet Media API to access real-time media from a conference, the Google Cloud project, OAuth principal, and all participants in the conference must be enrolled in the Developer Preview Program.**\n\nA helper class that can be used to get and subscribe to updates on a value.\n\nSignature\n---------\n\n interface Subscribable\u003cT\u003e\n\nType parameters\n---------------\n\n| Name | Optional | Constraint | Default |\n|------|----------|------------|---------|\n| `T` | No | | |\n\nMethod signatures\n-----------------\n\n| Name | Description |\n|------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------|\n| [`get()`](./media_api_web.subscribable.get.md) | |\n| [`subscribe(callback)`](./media_api_web.subscribable.subscribe.md) | Allows a callback to be added. This callback will be called whenever the value is updated. |\n| [`unsubscribe(callback)`](./media_api_web.subscribable.unsubscribe.md) | Removes the callback from the list of subscribers. The original callback instance must be passed in as an argument. |"]]