If you haven't already, create a new app in the Developer Portal⁠(opens in a new tab or window). For more information, refer to our Quickstart guide.
In your app's configuration on the Developer Portal⁠(opens in a new tab or window), ensure the "Development URL" is set to http://localhost:8080.

Clone the starter kit:

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

SHELL

Install dependencies:
```
npm install
```
SHELL
Run the example:
```
npm run start image_replacement
```
SHELL
Click the Preview URL link shown in the terminal to open the example in the Canva editor.

Example app source code

// For usage information, see the README.md file.
import { useState } from "react";
import { upload } from "@canva/asset";
import { Button, Rows, Text } from "@canva/app-ui-kit";
import { useSelection } from "utils/use_selection_hook";
import * as styles from "styles/components.css";

export const App = () => {
  const [loading, setLoading] = useState(false);
  // Hook to monitor image element selection in the Canva editor
  // Only triggers when image elements are selected by the user
  const selection = useSelection("image");

  const updateImage = async () => {
    setLoading(true);

    // Upload a new image using Canva's asset API
    // This creates a queued image that can be referenced in the design
    const queuedImage = await upload({
      type: "image",
      url: "https://www.canva.dev/example-assets/image-import/image.jpg",
      mimeType: "image/jpeg",
      thumbnailUrl:
        "https://www.canva.dev/example-assets/image-import/thumbnail.jpg",
      aiDisclosure: "none",
    });

    // Read the current selection draft to modify selected image elements
    const draft = await selection.read();
    // Replace each selected image's reference with the new uploaded image
    draft.contents.forEach((s) => (s.ref = queuedImage.ref));
    // Save the changes to update the design with the new image
    await draft.save();

    setLoading(false);
  };

  return (
    <div className={styles.scrollContainer}>
      <Rows spacing="2u">
        <Text>
          This example demonstrates how apps can replace the selected image.
          Select an image in the editor to begin.
        </Text>
        <Button
          variant="primary"
          onClick={updateImage}
          disabled={selection.count === 0}
          loading={loading}
        >
          Replace with sample image
        </Button>
      </Rows>
    </div>
  );
};

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";

const root = createRoot(document.getElementById("root") as Element);
function render() {
  root.render(
    <AppUiProvider>
      <App />
    </AppUiProvider>,
  );
}

render();

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

TYPESCRIPT

# Image replacement

Demonstrates how to replace selected image elements in a design with new image content. Shows selection detection, image upload, and content replacement patterns for updating existing design elements using the Canva Apps SDK.

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

Related examples: See content_replacement/video_replacement for video substitution patterns, or asset_upload for general image import and upload workflows.

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
- Image format validation is not implemented. Production apps should validate image 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
- Loading states and progress indicators are basic. Production apps should provide detailed progress feedback for long-running operations

MARKDOWN

API reference

Need help?

Join our Community Forum⁠(opens in a new tab or window)
Report issues with this example on GitHub⁠(opens in a new tab or window)