I am getting weird output but no errors in Flutter weather application

Question

I am getting weird output but no errors.

1) location_handler.dart

import 'package:geolocator/geolocator.dart';

class Locator {
  //Locator({this.latitude, this.longitude});

  double? latitude;
  double? longitude;

  Future<void> getCurrentLocation() async {
    //'async' means that this function might take unknown amount of time
    //so we put async to put this operation to happen in the background.
    try {
      //using try catch block to prevent errors.
      Position posi = await Geolocator.getCurrentPosition(
          desiredAccuracy: LocationAccuracy.low);
      //set to low to save battery since you just need weather info.
      latitude = posi.latitude;
      longitude = posi.longitude;
    } on Exception catch (e) {
      print(e);
    }
  }
}

2) loading_screen.dart

import 'package:flutter/material.dart';
import 'package:clima/services/location_handler.dart';
import 'dart:convert'; //imported to convert/use JSON data into our project.
import 'package:http/http.dart' as http;

const myAPI = 'cant show but I have registerd and working key';

class LoadingScreen extends StatefulWidget {
      @override
      _LoadingScreenState createState() => _LoadingScreenState();
    }
    
    class _LoadingScreenState extends State<LoadingScreen> {
      late double latitood;
      late double longitood;
    
      void initState() {
        //this method is called the moment we run our app.
        super.initState();
        getLocation();
      }
    
      void getLocation() async {
        Locator loca = Locator();
        await loca.getCurrentLocation();
        latitood = loca.latitude!; //'!' is null-check.
        longitood = loca.longitude!;
        getData();
      }
    
      void getData() async {
        Uri uri = Uri.https(
          /*A Uniform Resource Identifier is a unique sequence of characters
          that identifies a logical or physical resource used by web technologies.*/
          'api.openweathermap.org', //Authority(string)
          '/data/2.5/weather', //Path(string)
          {'lat': latitood, 'lon': longitood, 'appid': myAPI},
          //Parameters of Query
        );
        http.Response response = await http.get(uri);
        //passing uri to get method to get Response.
        print(response.statusCode);
        if (response.statusCode == 200) {
          String data = response.body;
          var decodedData = jsonDecode(data);
          //decoding and putting data into decodedData variable of dynamic type.
    
          int weatherCondition = decodedData['weather'][0]['id'];
          //gets weather condition.
          print(weatherCondition);
    
          double temperature = decodedData['main']['temp'];
          //for temperature.
          print(temperature);
    
          String cityName = decodedData['name'];
          //city name.
          print(cityName);
        } else {
          print(response.statusCode);
        }
      }
    
      @override
      Widget build(BuildContext context) {
        return Scaffold();
      }
    }  

Output:

Performing hot restart...

Syncing files to device moto g52...

Restarted application in 1,518ms.

E/flutter ( 4024): [ERROR:flutter/lib/ui/ui_dart_state.cc(198)] Unhandled Exception: type 'double' is not a subtype of type 'Iterable'

E/flutter ( 4024): #0 _Uri._makeQuery. (dart:core/uri.dart:2356:18)

E/flutter ( 4024): #1 _LinkedHashMapMixin.forEach (dart:collection-patch/compact_hash.dart:614:13)

E/flutter ( 4024): #2 _Uri._makeQuery (dart:core/uri.dart:2352:21)

E/flutter ( 4024): #3 new _Uri (dart:core/uri.dart:1643:13)

E/flutter ( 4024): #4 _Uri._makeHttpUri (dart:core/uri.dart:1782:12)

E/flutter ( 4024): #5 new _Uri.https (dart:core/uri.dart:1678:12)

E/flutter ( 4024): #6 _LoadingScreenState.getData (package:clima/screens/loading_screen.dart:37:19)

E/flutter ( 4024): #7 _LoadingScreenState.getLocation (package:clima/screens/loading_screen.dart:33:5)

E/flutter ( 4024):

E/flutter ( 4024):

Problem: I should be getting Weather condition, temperature, and City name. But I am getting all this please help.

Answer 1

Solved the problem. Just had to add 'late' keyword for both longitood and latitood variables of type double and do certain tweaks in the code.

Instead of:

 void getData() async {
            Uri uri = Uri.https(
              /*A Uniform Resource Identifier is a unique sequence of characters
              that identifies a logical or physical resource used by web technologies.*/
              'api.openweathermap.org', //Authority(string)
              '/data/2.5/weather', //Path(string)
              {'lat': latitood, 'lon': longitood, 'appid': myAPI},
              //Parameters of Query
            );

Adding $ and putting '' did the deed:

void getData() async {
    Uri uri = Uri.https(
      /*A Uniform Resource Identifier is a unique sequence of characters
      that identifies a logical or physical resource used by web technologies.*/
      'api.openweathermap.org', //Authority(string)
      '/data/2.5/weather', //Path(string)
      {'lat': '$latitood', 'lon': '$longitood', 'appid': myAPI},
      //Parameters of Query
    );