> ## Documentation Index
> Fetch the complete documentation index at: https://www.canva.dev/docs/button/llms.txt
> Use this file to discover all available pages before exploring further.

# onDesignOpen

API reference for the JavaScript API's onDesignOpen method.

A function that runs when a user opens a design. This includes when a user creates a new design or edits an existing design.

## Usage

```javascript
api.createDesign({
  design: {
    type: "Poster",
  },
  onDesignOpen: (opts) => {
    console.log(opts);
  },
});
```

**Tip:**
You can pass the `onDesignOpen` function into the [`createDesign`](https://www.canva.dev/docs/button/javascript/api-reference/create-design/) and [`editDesign`](https://www.canva.dev/docs/button/javascript/api-reference/edit-design/) functions.

## Parameters

| Name               | Type   | Required | Description                                     |
| :----------------- | :----- | :------: | :---------------------------------------------- |
| `opts`             | object |    Yes   | Parameters that Canva passes into the function. |
| `opts.designId`    | string |    Yes   | The ID of the user's design.                    |
| `opts.designTitle` | string |    Yes   | The title of the user's design.                 |

## Returns

`void`