Question 75940 in Flutter Question posted in
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How can I read Data from a JSON File and display it in Flutter Widgets?

I would like to use my JSON file to store all the info in it to display in Flutter.
Everytime i get this Error:
_TypeError (type '_InternalLinkedHashMap<String, dynamic>' is not a subtype of type 'List<dynamic>')

Here are my Files:
db.json
breed_page.dart

Can someone help me solving this error or show me a better way to do this?

Normally, the name and image should be read from the JSON file and then displayed in the list tile as a circle image or as text. I have also checked my JSON file and tried other functions like this one but nothing helped. By the way I am a newbie in Flutter

ListView.builder(
  itemCount: breeds.length,
  itemBuilder: (BuildContext context, int index) {
    return ListTile(
      leading: Image.network(breeds[index]['img']),
      title: Text(breeds[index]['name']),
      onTap: () {
        // TODO: Navigate to breed details page
      },
    );
  },
);
Tags:

2

Answers


  1. 0

    json.decode(jsonString); seems to be converting the data from String to Map<String, dynamic> instead of List<dynamic>

    Please go through the language docs to check if you’re using the right return type for your json
    https://api.dart.dev/stable/2.19.3/dart-convert/jsonDecode.html

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  2. 0

    your decoded json string is Map<String,dynamic> not a List<dynamic>

    {
    "breeds":[
       {

    the List are a value from key breeds

    Workaroud:

      Future<List<dynamic>> fetchBreeds() async {
    String jsonString = await rootBundle.loadString('lib/db.json');
   final tempDecoded = json.decode(jsonString);
   // now get the list with key breeds
   final breeds = tempDecoded["breeds"];
    return breeds;
  }
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