fabb.dart

FloatingActionButton(
  child: Icon(Icons.camera_alt),
  // Provide an onPressed callback.
  onPressed: () async {
    // Take the Picture in a try / catch block. If anything goes wrong,
    // catch the error.
    try {
      // Ensure that the camera is initialized.
      await _initializeControllerFuture;

      // Construct the path where the image should be saved using the path
      // package.
      final path = join(
        // Store the picture in the temp directory.
        // Find the temp directory using the `path_provider` plugin.
        (await getTemporaryDirectory()).path,
        '${DateTime.now()}.png',
      );

      // Attempt to take a picture and log where it's been saved.
      await _controller.takePicture(path);
    } catch (e) {
      // If an error occurs, log the error to the console.
      print(e);
    }
  },
)