I want to use CoinMarketCap API in flutter. But where I want to add data from map to list, an error will occur which says:
type 'string' is not a subtype of type 'int' of 'index'.
here's my code, I used this tutorial Migrating to the new CoinMarketCap API with Flutter
Future<void> getCryptoPrices() async{
List cryptoDatas = [];
print('Crypto Prices are Loading...');
String apiURL= "https://pro-api.coinmarketcap.com/v1/cryptocurrency/listings/latest";
http.Response response = await http.get(apiURL, headers: {'X-CMC_PRO_API_KEY': 'api code'});
Map<String, dynamic> responseJSON = json.decode(response.body);
if (responseJSON["status"]["error_code"] == 0) {
for (int i = 1; i <= responseJSON["data"].length; i++) {
cryptoDatas.add(responseJSON["data"][i.toString()]); // THE ERROR WILL HAPPEND HERE
}
}
setState(() {
this.cryptoList = cryptoDatas;
print(cryptoList);
});
Thank you in advance.
I had this same problem today, and I fixed it with this code. The code is a little different from yours but should do the same thing. If it didn't work then let me know.
Future<String> getCryptoPrices() async {
// API URL
var response = await http.get(
Uri.parse("API URL"),
// Only Accepts data in the formate of json
headers: {
"Accept": "application/json",
});
// this gets the data from the json
var first = json.decode(response.body);
//this is optional if you want to filter through the data
var second = first['current'];
var third = second['temp'];
// this prints out the data from the json
setState(() {
print(third);
});
}
change this line
cryptoDatas.add(responseJSON["data"][i.toString()])
to:
cryptoDatas.add(responseJSON["data"][i])
Related
I want to send a GET http request with parameters, my problem is that when I add the parameters in the request URL manually it works fine, but when I pass them as parameters it returns an exception without any explanation and somehow the execution stops after Uri.https
here is the code that I want to achieve
Future<List<LawFirm>> getLawFirms () async {
Map<String, dynamic> parameters = {
'total': true
};
final uri =
Uri.http('www.vision.thefuturevision.com:5000',
'/api/law-firm', parameters);
final response = await http.get(uri);
var dynamicResponse = jsonDecode(response.body);
totaLawFirms = await dynamicResponse['total'];
var lawFirms = await dynamicResponse['data'];
List<LawFirm> list = List<LawFirm>.from(lawFirms.map((x) => LawFirm.fromJson(x)));
print(list);
notifyListeners();
return list;
}
and here is the manual way which shouldn't be applied
final response = await get(Uri.parse('$baseURL/law-firm?total=true'));
I have also tried the dio library from pub.dev but also wasn't helpful.
And finally thanks in advance to everyone
You may try this
Map<String, dynamic> parameters = {
'total': true
};
var uri = Uri(
scheme: 'http',
host: 'www.vision.thefuturevision.com:5000',
path: '/law-firm',
queryParameters: parameters,
);
final response = await http.get(uri);
import 'package:http/http.dart' as http;
final response =
await http.get(Uri.parse("${Constants.baseUrl}endpoint/param1/param2"));
Just modify your GET request like this.
Try this
import 'package:http/http.dart' as http;
callAPI() async {
String login = "sunrule";
String pwd = "api";
Uri url = Uri.parse(
"http://vijayhomeservices.in/app/api/index.php?apicall=login&login=$login&password=$pwd");
final response = await http.get(url);
if (response.statusCode == 200) {
final body = json.decode(response.body);
print(body.toString());
} else {
throw Exception("Server Error !");
}
}
Query parameters don't support bool type. Use String instead: 'true'.
A value in the map must be either a string, or an Iterable of strings, where the latter corresponds to multiple values for the same key.
Map<String, dynamic> parameters = {'total': 'true'};
final uri = Uri.http(
'www.vision.thefuturevision.com:5000', '/api/law-firm', parameters);
print(uri); // http://www.vision.thefuturevision.com:5000/api/law-firm?total=true
See Uri constructor for details.
This is my simple code
try{
final dynamic headers = await _getReqHeader();
http.Response res = await http.get(Uri.parse(url), headers: headers);
print("Dres2="+res.toString());
return _result(res);
}catch(e){
print("Dres3="+e.toString());
return _result({});
}
This code works well. But when use some url's I get type '_SimpleUri' is not a subtype of type 'String' error. In postman this url works perfectly. I could not find any information about _SimpleUri. How can I solve this problem?
The get method of the http package takes Uri.https(hostUrl , apiEndpoint) not Uri.parse.
The error appears because a simple URLs being passed to it. To fix this, you have to do this:
http.Response res = await http.get(Uri.https(host, url), headers: headers);
I had a similar issue and that's how I solved it.
static const baseUrl = "apihost.com";
Future<http.Response> _get(String url, {host = baseUrl}) async {
final header = <String, String>{};
return http.get(Uri.https(host, url), headers: header);
}
Future<String?> getData() async {
final response = await _get("/endpoint");
if (isSuccessful(response)) {
final json = jsonDecode(response.body);
} else {
print('GET failed [${response.statusCode}]:
${response.body}');
return null;
}
}
Im trying to get json data from the server
here is the code:
void main() async{
List data = await getData();
print(data);
runApp(MyApp());
}
Future<List> getData() async {
String myUrl = "https://dashboard.ssitanas.com/public/api/categories";
http.Response response = await http.get(myUrl, headers: {
'Accept': 'application/json',
});
return json.decode(response.body);
}
what is the problem ?
The response coming from the api is a Map, not a List, but from the looks of things, there seems to be a list inside the map
so just do this :
var res = json.decode(response.body);
var listData = res["data"];
//assuming the list inside the map is called data
return listData;
I have a scenario where the following function is called again and again whenever the user hits the "Load More" button.
The problem I'm facing is, that it replaces previously loaded data with a new one. Instead, it should add to the bottom of the Listview.Builder
Future fetchData() async{
var url = "url_goes_here";
final response = await http.get(url);
if (response.statusCode == 200) {
var resBody = jsonDecode(response.body);
var data = resBody['data'] as List;
if (data.isNotEmpty) {
setState(() {
listVariable = data
.map<ModelClass>((json) => ModelClass.fromJson(json))
.toList();
});
}
}
}
List<ModelClass> listVariable =List<ModelClass>(); //describe the object that way.
--------and---------
data.map<ModelClass>((json) {
listVariable.add(ModelClass.fromJson(jsonn));
} )).toList();
You should add received data to your listVariable, not assign a new value. Try this code:
final listVariable = <ModelClass>[];
...
Future fetchData() async {
var url = "url_goes_here";
final response = await http.get(url);
if (response.statusCode == 200) {
var resBody = jsonDecode(response.body);
var data = resBody['data'] as List;
if (data.isNotEmpty) {
final list = data.map<ModelClass>((json) => ModelClass.fromJson(json));
setState(() {
listVariable.addAll(list); // HERE: addAll() instead of assignment
});
}
}
}
I was able to figure out answer myself.
setState(() {
listVariable.addAll(data
.map<ModelClass>((json) => ModelClass.fromJson(json))
.toList();
}));
#Mol0ko and #hasan karaman both are right but #Mol0ko
Makes better sense when you have a set of data to addAll to existing data.
I already have a button to fetch the API with function to ++increment index and set the new parameter on every click. My question is, how to set 'like a cache' for json response as index?
here my http.post request =
List<dynamic> _myResponse = [];
Future<void> trytoFetch(myIndex, parameter) async {
var url =
"https://jsonplaceholder.typicode.com/posts/$parameter";
Map<String, String> headers = {
'Content-type': 'application/json',
'Accept': 'application/json',
};
final response = await http.post(url, headers: headers);
final responseJson = json.decode(response.body);
if (response.statusCode == 200) {
setState(() {
_myResponse[myIndex] = responseJson; // ITS DOESNT WORKS
});
} else {
setState(() {});
throw Exception('Failed to load internet');
}
}
My goal is like
if (response.statusCode == 200) {
setState(() {
_myResponse[0] = responseJson; // return responseJson from parameter
// Then I click the button with new parameter value and increment index
_myResponse[1] = responseJson; // return responseJson from new parameter
// Then I click the button with another new parameter value and increment index
_myResponse[2] = responseJson; // return responseJson from new parameter again
});
} else {
setState(() {});
throw Exception('Failed to load internet');
}
and in the end, I can simply print the returned json
print(_myResponse[0]);
print(_myResponse[1]);
print(_myResponse[2]);
How to achieve this? is it possible? Thanks
First of, you shouldn't pass index as a parameter to your method.
responseJson variable is a Map, you should convert that map to the object you need.
I suggest taking a look at this.