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

# Video replacement

Replace selected video elements in designs with custom content.

## Running this example

To run this example locally:

1. If you haven't already, create a new app in the [Developer Portal](https://www.canva.com/developers/apps). For more information, refer to our [Quickstart guide](https://www.canva.dev/docs/apps/quickstart/).

2. In your app's configuration on the [Developer Portal](https://www.canva.com/developers/apps), ensure the "Development URL" is set to `http://localhost:8080`.

3. Clone the starter kit:

   ```shell
   git clone https://github.com/canva-sdks/canva-apps-sdk-starter-kit.git
   cd canva-apps-sdk-starter-kit
   ```

4. Install dependencies:

   ```shell
   npm install
   ```

5. Run the example:
   ```shell
   npm run start:example video_replacement
   ```

6. Click the **Preview URL** link shown in the terminal to open the example in the Canva editor.

## Example app source code

<Tabs>
  <Tab name="app.tsx">
    ```typescript
    // For usage information, see the README.md file.
    import { Button, Rows, Text } from "@canva/app-ui-kit";
    import { useState } from "react";
    import * as styles from "styles/components.css";
    import { upload } from "@canva/asset";
    import { useSelection } from "@canva/app-hooks";

    export const App = () => {
      const [loading, setLoading] = useState(false);
      // Monitor selection for video elements in the design
      const selection = useSelection("video");

      const updateVideo = async () => {
        setLoading(true);
        // Upload video asset to Canva's media storage
        const queuedVideo = await upload({
          type: "video",
          mimeType: "video/mp4",
          thumbnailImageUrl:
            "https://www.canva.dev/example-assets/video-import/beach-thumbnail-image.jpg",
          thumbnailVideoUrl:
            "https://www.canva.dev/example-assets/video-import/beach-thumbnail-video.mp4",
          url: "https://www.canva.dev/example-assets/video-import/beach-video.mp4",
          width: 320,
          height: 180,
          aiDisclosure: "none",
        });
        // Create a draft to modify the selected video elements
        const draft = await selection.read();
        // Replace each selected video's content with the new uploaded video
        draft.contents.forEach((s) => (s.ref = queuedVideo.ref));

        // Apply changes to the design
        await draft.save();
        setLoading(false);
      };
      return (
        <div className={styles.scrollContainer}>
          <Rows spacing="2u">
            <Text>
              This example demonstrates how apps can replace the selected video.
              Select a video in the editor to begin.
            </Text>
            <Button
              variant="primary"
              onClick={updateVideo}
              disabled={selection.count === 0}
              loading={loading}
            >
              Replace with sample video
            </Button>
          </Rows>
        </div>
      );
    };
    ```
  </Tab>

  <Tab name="index.tsx">
    ```typescript
    // For usage information, see the README.md file.
    import { createRoot } from "react-dom/client";
    import { App } from "./app";
    import "@canva/app-ui-kit/styles.css";
    import { AppUiProvider } from "@canva/app-ui-kit";
    import type { DesignEditorIntent } from "@canva/intents/design";
    import { prepareDesignEditor } from "@canva/intents/design";

    async function render() {
      const root = createRoot(document.getElementById("root") as Element);

      root.render(
        <AppUiProvider>
          <App />
        </AppUiProvider>,
      );
    }

    const designEditor: DesignEditorIntent = { render };
    prepareDesignEditor(designEditor);

    // Hot Module Replacement for development (automatically reloads the app when changes are made)
    if (module.hot) {
      module.hot.accept("./app", render);
    }
    ```
  </Tab>

  <Tab name="README.md">
    ```markdown
    # Video replacement

    Demonstrates how to replace selected video elements in a design with new video content. Shows selection detection, video upload, and content replacement patterns for updating existing design elements.

    For API reference docs and instructions on running this example, see: <https://www.canva.dev/docs/apps/examples/video-replacement/>.

    Related examples: See content_replacement/image_replacement for image substitution, or asset_upload for general video import patterns.

    NOTE: This example differs from what is expected for public apps to pass a Canva review:

    - Static assets are used for demonstration purposes only. Production apps should host assets on a CDN/hosting service and use the `upload` function from the `@canva/asset` package
    - Video format validation is not implemented. Production apps should validate video formats and handle unsupported formats gracefully
    - Error handling is simplified for demonstration. Production apps must implement comprehensive error handling with clear user feedback and graceful failure modes
    - Internationalization is not implemented. Production apps must support multiple languages using the `@canva/app-i18n-kit` package to pass Canva review requirements
    - The code structure is simplified: Production apps using [intents](https://www.canva.dev/docs/apps/intents/) are recommended to call the prepareDesignEditor function from src/intents/design_editor/index.tsx
    ```
  </Tab>
</Tabs>

## API reference

* [App UI Kit](https://www.canva.dev/docs/apps/app-ui-kit/)
* [`prepareDesignEditor`](https://www.canva.dev/docs/apps/api/latest/intents-design-prepare-design-editor/)
* [`upload`](https://www.canva.dev/docs/apps/api/latest/asset-upload/)

## Need help?

* Join our [Community Forum](https://community.canva.dev/)
* Report issues with this example on [GitHub](https://github.com/canva-sdks/canva-apps-sdk-starter-kit/issues)