Is it possible to count the API calls via Interceptors?
For example: If an API (with the same parameters and same endpoint) gets called more than three times, I will show a popup widget.
Yes, it is possible to count API calls via interceptors in Flutter. using Dio Package
here is a example :-
import 'dart:js';
import 'package: flutter/material.dart';
import 'package:dio/dio.dart';
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
appBar: AppBar(
title: const Text('API Calls Counter Demo'),
),
body: Center(
child: ElevatedButton(
onPressed: _fetchData,
child: const Text('Fetch Data'),
),
),
),
);
}
void _fetchData() async {
final dio = Dio();
const key = 'http://localhost:8080/police/';
int count = 0;
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
appBar: AppBar(
title: const Text('API Calls Counter Demo'),
),
body: Center(
child: ElevatedButton(
onPressed: _fetchData,
child: const Text('Fetch Data'),
),
),
),
);
}
dio.interceptors.add(InterceptorsWrapper(
onRequest: (options, handler) {
if (options. Path == key && count++ >= 8) {
_showPopupWidget(context as BuildContext);
}
handler. Next(options);
},
));
try {
final response = await dio.get(key);
print(response.data);
} catch (e) {
print(e);
}
}
void _showPopupWidget(BuildContext context) {
showDialog(
context: context,
builder: (context) => AlertDialog(
title: const Text('API Calls Counter'),
content: const Text('This API has been called more than 8 times.'),
actions: <Widget>[
TextButton(
onPressed: () => Navigator.pop(context),
child: const Text('OK'),
),
],
),
);
}
Related
I was just put official Doc code for see how Navigation work in web(chrome). But when I click button I get an error->
Navigator operation requested with a context that does not include a Navigator.
code->
import 'package:flutter/material.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
appBar: AppBar(
title: Text('First Route'),
),
body: Center(
child: ElevatedButton(
child: Text('Open route'),
// Within the `FirstRoute` widget
onPressed: () {
Navigator.push(
context,
MaterialPageRoute(builder: (context) => SecondRoute()),
);
}),
),
),
);
}
}
class SecondRoute extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Second Route"),
),
body: Center(
child: ElevatedButton(
// Within the SecondRoute widget
onPressed: () {
Navigator.pop(context);
},
child: Text('Go back!'),
),
),
);
}
}
Thanks...
How to use MaterialPageRoute with a new file dart?
My codes:
main.dart
import 'package:flutter/material.dart';
import 'package:hello_world/settings_page.dart';
void main() => runApp(Belajar());
class Belajar extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
appBar: AppBar(
leading: Icon(Icons.android),
title: Text('Hello World'),
actions: [
IconButton(
icon: Icon(Icons.settings),
onPressed: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) {
return SettingsPage();
},
),
);
},
)
],
),
),
);
}
}
settings_page.dart
import 'package:flutter/material.dart';
class SettingsPage extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
leading: IconButton(
icon: Icon(Icons.arrow_back),
onPressed: () {
Navigator.pop(context);
},
),
),
);
}
}
I tried the code above. But, give me an error:
Navigator operation requested with a context that does not include a Navigator.
What wrong with my code?
you are missing just one thing
MaterialApp(
home:Builder(
//use this context to push new route
builder:(context){
return Scaffold(
appBar://..
);
}
)
)
here builder will introduce a new context which will contain the navigator introduced by material app
First create a class for example runFunction()
and you can use these code for going to that screen
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => runFunction(),
),
);
an example of runFuction
class _recipeSearchState extends State<recipeSearch> {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('hello'),
),
body: SingleChildScrollView(
scrollDirection: Axis.vertical,
child: Column(
children: [
Text("Text"),
],
),
),
);
}
}
Just wonder if I use this code to return PageA from PageD, which function will it get called in PageA?
PageD
Navigator.of(context).popUntil(ModalRoute.withName(PageA.ROUTE));
I would like to make the listView on PageA refreshed once it is back from PageD, but I don't know how to achieve it.
I added a then in PageA, but it is not printing anything.
Navigator.pushNamed(context, PageB.ROUTE).then((onValue) {
print("call from Page4");
_refreshListView();
});
Edit
My project flow is Page A > Page B > Page C > Page D > page A.
All you need to do is return data when you pop PageD and await the data when you push.
This code should help:
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
// This widget is the root of your application.
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
initialRoute: '/',
routes: {
'/' : (context) => PageA(),
'/go': (context) => PageD()
},
);
}
}
class PageA extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Page A"),
),
body: Center(
child: ListView(
children: <Widget>[
],
),
),
floatingActionButton: FloatingActionButton(
onPressed: () {
_navigateAndDisplaySelection(context);
},
child: Icon(Icons.forward),
),
);
}
_navigateAndDisplaySelection(BuildContext context) async {
final result = await Navigator.pushNamed(
context,
'/go'
);
if(result){
print(result);
//call the refresh ListView here
_refreshListView();
}
}
}
class PageD extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Page D"),
leading: IconButton(
icon: Icon(Icons.arrow_back, color: Colors.white,),
onPressed: (){
Navigator.pop(context, true);
},
)
),
body: Center(
child: Text("Press back!!"),
),
);
}
}
As to what you explained in the comments... you have to pass arguments from Page D to A when navigating.
Hope this helps.
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
// This widget is the root of your application.
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
initialRoute: '/',
routes: {
'/': (context) => PageA(),
'/b': (context) => PageB(),
'/c': (context) => PageC(),
'/d': (context) => PageD()
},
);
}
}
class PageA extends StatelessWidget {
#override
Widget build(BuildContext context) {
final bool shouldRefresh = ModalRoute.of(context).settings.arguments;
if (shouldRefresh != null) {
print(shouldRefresh);
//call the refresh ListView here
_refreshListView();
}
return Scaffold(
appBar: AppBar(
title: Text("Page A"),
),
body: Center(
child: ListView(
children: <Widget>[],
),
),
floatingActionButton: FloatingActionButton(
onPressed: () {
Navigator.pushNamed(context, '/b');
},
child: Icon(Icons.forward),
),
);
}
}
class PageB extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Page B"),
),
floatingActionButton: FloatingActionButton(
child: Icon(Icons.forward),
onPressed: () {
Navigator.pushNamed(context, '/c');
},
),
);
}
}
class PageC extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Page C"),
),
floatingActionButton: FloatingActionButton(
child: Icon(Icons.forward),
onPressed: () {
Navigator.pushNamed(context, '/d');
},
),
);
}
}
class PageD extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Page D"),
leading: IconButton(
icon: Icon(
Icons.arrow_back,
color: Colors.white,
),
onPressed: () {
Navigator.pushNamed(context, '/', arguments: true);
},
)),
body: Center(
child: Text("Press back!!"),
),
);
}
}
If you want to go to Page D when you press back in Page A then use this
class PageA extends StatelessWidget {
#override
Widget build(BuildContext context) {
final bool shouldRefresh = ModalRoute.of(context).settings.arguments;
print(shouldRefresh);
return Scaffold(
appBar: AppBar(
title: Text("Page A"),
leading: IconButton(
icon: Icon(
Icons.arrow_back,
color: Colors.white,
),
onPressed: () {
Navigator.pushNamed(
context,
'/d',
arguments: true
);
},
),
),
body: Center(
child: ListView(
children: <Widget>[
],
),
),
floatingActionButton: FloatingActionButton(
onPressed: () {
Navigator.pushNamed(context, '/b');
},
child: Icon(Icons.forward),
),
);
}
}
i am trying to go on another page using navigation, but i am getting error;
Navigator operation requested with a context that does not include a
Navigator.
i am just trying to move on next page, i followed flutter documentations for this stateless widget but how to do with state full widget.
import 'package:flutter/material.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatefulWidget {
#override
State createState() => new MyApp1();
}
class MyApp1 extends State<MyApp> {
List<Widget> _listSection = [];
Widget build(BuildContext context) {
return MaterialApp(
debugShowCheckedModeBanner: false,
title: 'Share IDEASS',
initialRoute: '/',
routes: {
'/second': (context) => SecondScreen(),
},
home: Scaffold(
appBar: AppBar(
title: Text('IDEAS'),
),
body: Container(
child: Stack(
children: [
floatingButton(),
],
),
),
),
);
}
Widget floatingButton() {
return Container(
padding: const EdgeInsets.all(30),
alignment: Alignment.bottomRight,
child: FloatingActionButton(
onPressed: () {
Navigator.pushNamed(context, "/SecondScreen");
},
child: Text("+"),
backgroundColor: Colors.blue,
),
);
}
}
class SecondScreen extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Second Route"),
),
body: Center(
child: RaisedButton(
onPressed: () {
Navigator.pop(context);
},
child: Text('Go back!'),
),
),
);
}
}
You should use the named route you created.
Widget floatingButton(BuildContext context) { // added context as a parameter
return Container(
padding: const EdgeInsets.all(30),
alignment: Alignment.bottomRight,
child: FloatingActionButton(
onPressed: () {
Navigator.pushNamed(context, "/second"); // Changed this to use the named route
},
child: Text("+"),
backgroundColor: Colors.blue,
),
);
}
}
then use the following
body: Container(
child: Stack(
children: [
floatingButton(context),
],
),
),
The situation here is that the floatingButton() uses a context with the navigator to push the given page route. But the context used is provided in the parent Widget(MaterialApp) it self, which doesn't include a Navigator, hence the error.
So, Try this approach:
Separate the Home widget from the MaterialApp, like below:
return MaterialApp(
debugShowCheckedModeBanner: false,
title: 'Share IDEASS',
initialRoute: '/',
routes: {
'/second': (context) => SecondScreen(),
},
home: HomePage(),
);
Create a stateless widget containing the Scaffold:
class HomePage extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('IDEAS'),
),
body: Container(
child: Stack(
children: [
floatingButton(),
],
),
),
);
}
}
Hope it helps. Let me know if this doesn't work.
You have made two mistakes because of which your code is not working:
You have used wrong route name. Replace /SecondScreen with /second
You have used wrong context. You can get Navigator only if your widget has MaterialApp as it's parent and here you are using context of MyApp1 so it is not working.
Following is a working code for your reference.
import 'package:flutter/material.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatefulWidget {
#override
State createState() => new MyApp1();
}
class MyApp1 extends State<MyApp> {
List<Widget> _listSection = [];
Widget build(BuildContext context) {
return MaterialApp(
debugShowCheckedModeBanner: false,
title: 'Share IDEASS',
initialRoute: '/',
routes: {
'/second': (context) => SecondScreen(),
},
home: AppContent(),
);
}
}
class AppContent extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('IDEAS'),
),
body: Container(
child: Stack(
children: [
floatingButton(context),
],
),
),
);
}
Widget floatingButton(BuildContext context) {
return Container(
padding: const EdgeInsets.all(30),
alignment: Alignment.bottomRight,
child: FloatingActionButton(
onPressed: () {
Navigator.pushNamed(context, "/second");
},
child: Text("+"),
backgroundColor: Colors.blue,
),
);
}
}
class SecondScreen extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Second Route"),
),
body: Center(
child: RaisedButton(
onPressed: () {
Navigator.pop(context);
},
child: Text('Go back!'),
),
),
);
}
}
Is it possible to return to the exact same place meaning state wise in flutter while using this?
Navigator.of(context).push(new MaterialPageRoute(builder: (BuildContext context) => new ConnectHome(user:widget.user))));
We have cards on the home screen "ConnectHome()" and we need to return them to the same spot.
You can copy paste run full code below
You can await Navigator.push and In Navigator.pop include UserObject()
You can see the code continue execution and print UserObject()
code snippet
final result = await Navigator.push(
context,
MaterialPageRoute(builder: (context) => ConnectHome()),
);
print('result ${result.name}')
...
Navigator.pop(context, UserObject("hello","world"));
working demo
full code
import 'package:flutter/material.dart';
void main() {
runApp(MaterialApp(
title: 'Returning Data',
home: HomeScreen(),
));
}
class HomeScreen extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Returning Data Demo'),
),
body: Center(child: SelectionButton()),
);
}
}
class SelectionButton extends StatelessWidget {
#override
Widget build(BuildContext context) {
return RaisedButton(
onPressed: () {
_navigateAndDisplaySelection(context);
},
child: Text('Pick an option, any option!'),
);
}
// A method that launches the SelectionScreen and awaits the result from
// Navigator.pop.
_navigateAndDisplaySelection(BuildContext context) async {
// Navigator.push returns a Future that completes after calling
// Navigator.pop on the Selection Screen.
final result = await Navigator.push(
context,
MaterialPageRoute(builder: (context) => ConnectHome()),
);
print('result ${result.name}');
// After the Selection Screen returns a result, hide any previous snackbars
// and show the new result.
Scaffold.of(context)
..removeCurrentSnackBar()
..showSnackBar(SnackBar(content: Text("${result.name}")));
}
}
class UserObject {
String name;
String id;
UserObject(this.name, this.id);
}
class ConnectHome extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Pick an option'),
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Padding(
padding: const EdgeInsets.all(8.0),
child: RaisedButton(
onPressed: () {
// Close the screen and return "Yep!" as the result.
Navigator.pop(context, UserObject("hello","world"));
},
child: Text('Hello'),
),
),
Padding(
padding: const EdgeInsets.all(8.0),
child: RaisedButton(
onPressed: () {
// Close the screen and return "Nope!" as the result.
Navigator.pop(context, UserObject("no","No"));
},
child: Text('No.'),
),
)
],
),
),
);
}
}