如何在颤动中获取图像的路径？

Question

in my app y take a photo and then save it in the device, but then i dont know how to get the path of that image, cause the dir is root. this my code:

This is where i take the photo:

  Future<String> takePicture() async {
if (!controller.value.isInitialized) {
  showInSnackBar('Error: select a camera first.');
  return null;
}
final Directory extDir = await getApplicationDocumentsDirectory();
final String dirPath = '${extDir.path}/Pictures/flutter_test';
await new Directory(dirPath).create(recursive: true);
final String filePath = '$dirPath/${timestamp()}.jpg';

if (controller.value.isTakingPicture) {
  // A capture is already pending, do nothing.
  return null;
}

try {
  await controller.takePicture(filePath);
} on CameraException catch (e) {
  _showCameraException(e);
  return null;
}
return filePath;

}

this is the trigger:

  void onTakePictureButtonPressed() {
takePicture().then((String filePath) {
  if (mounted) {
    setState(() {
      imagePath = filePath;
      videoController?.dispose();
      videoController = null;
    });


    upload(File(filePath));

    print(filePath);
    if (filePath != null) showInSnackBar('Picture saved to $filePath');
  }
});

}

and this is where i want to send the image in formdata:

    upload(File imageFile) async {
  // open a bytestream
  var stream = new http.ByteStream(DelegatingStream.typed(imageFile.openRead()));
  // get file length
  var length = await imageFile.length();

  // string to uri
  var uri = Uri.parse("http://ip/something/else/here");

  // create multipart request
  var request = new http.MultipartRequest("POST", uri);

  // multipart that takes file
  var multipartFile = new http.MultipartFile('file', stream, length,
      filename: basename(imageFile.path));

  // add file to multipart
  request.files.add(multipartFile);

  // send
  var response = await request.send();
  print(response.statusCode);

  // listen for response
  response.stream.transform(utf8.decoder).listen((value) {
    print(value);
  });
}

when i take a photo thats returns:

{"error":"http: no such file"}

it's as if the api did not receive anything. i think is because the location is only root.

how can i modify that to access to the image?

Answer 1

I tried the code you've provided retaining only the parts to generate a file path and it works without issues. With getApplicationDocumentsDirectory() , I assume that you're using path_provider package.

Future<String> takePicture() async {
  // if (!controller.value.isInitialized) {
  //   showInSnackBar('Error: select a camera first.');
  //   return null;
  // }
  final Directory extDir = await getApplicationDocumentsDirectory();
  final String dirPath = '${extDir.path}/Pictures/flutter_test';
  await new Directory(dirPath).create(recursive: true);
  final String filePath = '$dirPath/${timestamp()}.jpg';

  // if (controller.value.isTakingPicture) {
  //   // A capture is already pending, do nothing.
  //   return null;
  // }

  // try {
  //   await controller.takePicture(filePath);
  // } on CameraException catch (e) {
  //   _showCameraException(e);
  //   return null;
  // }
  return filePath;
}

String timestamp() {
  // DateFormat uses intl package
  // https://pub.dev/packages/intl
  return DateFormat('y-MM-dd-HHms').format(DateTime.now());
}

I suggest verifying if the image has been created to troubleshoot the issue. The error from the logs provided seems to originate from your upload() task.

Also, DelegatingStream.typed() has been deprecated. Please http.ByteStream(StreamView<List<int>>).cast() instead.

Stream<List<int>> stream = http.ByteStream(imageFile.openRead()).cast();