Datasets:
Ekhlass
/
flutter_docs

Dataset card Data Studio Files
xet
Community
1
text
stringlengths
1
372
'title': string title,
} =>
album(
id: id,
title: title,
),
_ => throw const FormatException('Failed to load album.'),
};
}
}
<code_end>
<topic_end>
<topic_start>
convert the http.Response to an album
now, use the following steps to update the updateAlbum()
function to return a Future<Album>:
<code_start>
Future<Album> updateAlbum(String title) async {
final response = await http.put(
uri.parse('https://jsonplaceholder.typicode.com/albums/1'),
headers: <string, string>{
'content-type': 'application/json; charset=UTF-8',
},
body: jsonEncode(<String, string>{
'title': title,
}),
);
if (response.statuscode == 200) {
// if the server did return a 200 OK response,
// then parse the JSON.
return Album.fromJson(jsonDecode(response.body) as Map<String, dynamic>);
} else {
// if the server did not return a 200 OK response,
// then throw an exception.
throw Exception('Failed to update album.');
}
}
<code_end>
hooray!
now you’ve got a function that updates the title of an album.
<topic_end>
<topic_start>
4. get the data from the internet
get the data from internet before you can update it.
for a complete example, see the fetch data recipe.
<code_start>
Future<Album> fetchAlbum() async {
final response = await http.get(
uri.parse('https://jsonplaceholder.typicode.com/albums/1'),
);
if (response.statuscode == 200) {
// if the server did return a 200 OK response,
// then parse the JSON.
return Album.fromJson(jsonDecode(response.body) as Map<String, dynamic>);
} else {
// if the server did not return a 200 OK response,
// then throw an exception.
throw Exception('Failed to load album');
}
}
<code_end>
ideally, you will use this method to set
_futureAlbum during initState to fetch
the data from the internet.
<topic_end>
<topic_start>
5. update the existing title from user input
create a TextField to enter a title and a ElevatedButton
to update the data on server.
also define a TextEditingController to
read the user input from a TextField.
when the ElevatedButton is pressed,
the _futureAlbum is set to the value returned by
updateAlbum() method.
<code_start>
column(
mainAxisAlignment: MainAxisAlignment.center,
children: <widget>[
padding(
padding: const EdgeInsets.all(8),
child: TextField(
controller: _controller,
decoration: const InputDecoration(hintText: 'enter title'),
),
),
ElevatedButton(
onPressed: () {
setState(() {
_futureAlbum = updateAlbum(_controller.text);
});
},
child: const Text('Update data'),
),
],
);
<code_end>
on pressing the update data button, a network request
sends the data in the TextField to the server as a PUT request.
the _futureAlbum variable is used in the next step.
<topic_end>