text
stringlengths 1
372
|
---|
return padding(
|
padding: const EdgeInsets.all(10),
|
child: Text("Row ${widgets[i]["title"]}"),
|
);
|
}
|
future<void> loadData() async {
|
ReceivePort receivePort = ReceivePort();
|
await Isolate.spawn(dataLoader, receivePort.sendPort);
|
// the 'echo' isolate sends its SendPort as the first message.
|
SendPort sendPort = await receivePort.first;
|
list msg = await sendReceive(
|
sendPort,
|
'https://jsonplaceholder.typicode.com/posts',
|
);
|
setState(() {
|
widgets = msg;
|
});
|
}
|
// the entry point for the isolate.
|
static future<void> dataLoader(SendPort sendPort) async {
|
// open the ReceivePort for incoming messages.
|
ReceivePort port = ReceivePort();
|
// notify any other isolates what port this isolate listens to.
|
sendPort.send(port.sendPort);
|
await for (var msg in port) {
|
string data = msg[0];
|
SendPort replyTo = msg[1];
|
string dataURL = data;
|
http.Response response = await http.get(Uri.parse(dataURL));
|
// lots of JSON to parse
|
replyTo.send(jsonDecode(response.body));
|
}
|
}
|
future sendReceive(SendPort port, msg) {
|
ReceivePort response = ReceivePort();
|
port.send([msg, response.sendPort]);
|
return response.first;
|
}
|
}
|
<code_end>
|
<topic_end>
|
<topic_start>
|
what is the equivalent of OkHttp on flutter?
|
making a network call in flutter is easy when you use the
|
popular http package.
|
while the http package doesn’t have every feature found in OkHttp,
|
it abstracts away much of the networking that you would normally implement
|
yourself, making it a simple way to make network calls.
|
to add the http package as a dependency, run flutter pub add:
|
to make a network call, call await on the async function http.get():
|
<code_start>
|
import 'dart:developer' as developer;
|
import 'package:http/http.dart' as http;
|
future<void> loadData() async {
|
var dataURL = uri.parse('https://jsonplaceholder.typicode.com/posts');
|
http.Response response = await http.get(dataURL);
|
developer.log(response.body);
|
}
|
<code_end>
|
<topic_end>
|
<topic_start>
|
how do i show the progress for a long-running task?
|
in android you would typically show a ProgressBar view in your UI while
|
executing a long-running task on a background thread.
|
in flutter, use a ProgressIndicator widget.
|
show the progress programmatically by controlling when it’s rendered
|
through a boolean flag. tell flutter to update its state before your
|
long-running task starts, and hide it after it ends.
|
in the following example, the build function is separated into three different
|
functions. if showLoadingDialog is true (when widgets.isEmpty),
|
then render the ProgressIndicator. otherwise, render the
|
ListView with the data returned from a network call.
|
<code_start>
|
import 'dart:convert';
|
import 'package:flutter/material.dart';
|
import 'package:http/http.dart' as http;
|
void main() {
|
runApp(const SampleApp());
|
}
|
class SampleApp extends StatelessWidget {
|
const SampleApp({super.key});
|
@override
|
widget build(BuildContext context) {
|
return MaterialApp(
|
title: 'sample app',
|
theme: ThemeData(
|
colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
|
),
|
home: const SampleAppPage(),
|
);
|
}
|
}
|
class SampleAppPage extends StatefulWidget {
|
const SampleAppPage({super.key});
|
@override
|
State<SampleAppPage> createState() => _SampleAppPageState();
|
}
|
class _SampleAppPageState extends State<SampleAppPage> {
|
list widgets = [];
|
@override
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.