Dart/Flutter: not working function http.get

Question

I am very new to Flutter, and stuck at the following problem:

My function to get a list of books using googleapis:

    Future cercaLibri(String ricerca) async {
        final String dominio = 'www.googleapis.com';
        final String percorso = '/books/v1/volumes';
        Map<String, dynamic> parametri = {'q': ricerca};
    
        final Uri url = Uri.https(dominio, percorso, parametri);
        print('hello');
        http.get(url).then((res) {
          final resJson = json.decode(res.body);
          final libriMap = resJson['items'];
    
          libri = libriMap.map<Libro>((value) => Libro.fromMap(value)).toList();
    
          setState(() {
            libri = libri;
    
            risultato = res.body;
          });
        });
        setState(() {
          risultato = "Caricamento in corso";
        });
      }

for all files see stackblitz

In pubspec.yaml I have

http: ^0.13.4

It seems to me that the get method is not being called, or maybe the call is pending

Sorry the code isn't in English

Answer 1

I solved the problem call effect it works but it fails 'immagineCopertina' which sometimes returns null I added a control in Image.newtork by putting a dummy url if 'immagineCopertina' is null