Flutter Uploading Text File to Storage - firebase

Question

I'm trying to create a .txt file that contains the information from TextFieldController.
class FileUtils {
static Future<String> get getFilePath async {
final directory = await getApplicationDocumentsDirectory();
return directory.path;
}
static Future<File> get getFile async {
final path = await getFilePath;
return File('$path/myfile.txt');
}
static Future<File> saveToFile(String data) async {
final file = await getFile;
final neww = file.writeAsString(data);
return file.writeAsString(data);
}
static Future<String> readFromFile() async {
try {
final file = await getFile;
String fileContents = await file.readAsString();
return fileContents;
} catch (e) {
return "";
}
}
}
So, in the code above, I'm trying to create a .txt file that will be stored in Firebase Storage. In the code below, the user will input the information and that information will be saved to text file using the FileUtils' saveToFile function.
_dialog(BuildContext context) async {
await Future.delayed(Duration(seconds: 1));
return showDialog(
context: context,
builder: (context) {
return AlertDialog(
title: Text('Please write something'),
content: TextField(
controller: _textFieldController,
decoration: InputDecoration(hintText: ""),
maxLines: 5,
maxLength: 250,
),
actions: <Widget>[
new FlatButton(
child: new Text('Cancel'),
onPressed: () {
Navigator.of(context).pop();
},
),
new FlatButton(
child: new Text('Submit'),
onPressed: () {
FileUtils.saveToFile(_textFieldController.text);
Navigator.of(context).pop();
},
)
],
);
});
}
And I tried to store the text file using:
final test = FileUtils.getFile;
FirebaseStorage.instance.ref().child('test').putFile(test).onComplete;
but I failed. So, I need help storing .txt file to Firebase. I'm confused so I hope I was able to explain my problem.