Flutter

问题 How would one load a set of local images for display in a widget (noting this is async - see function below) triggered by (based on) a change in state from a flutter_bloc for “settings”? Noting this bloc is persisted too via hydrated_bloc. So the use case for which I’m asking how do I code this in flutter (noting I’m using flutter_bloc) is: Use Case - Render different set of images on the same Widget I have for dynamically displaying a room for a 2D point & click adventure type game, BASED ON

问题 I have this form that is filled out and then when submitted, it makes a separate List Tile in List View in Nosql. Here is the part where I make the 'food' item and on 'submit' button clicked, it makes the item and sends it to list view on the next screen. Notice how each food item has a uniqueID which is Uuid random string. class FoodForm extends StatefulWidget { final Food food; final int foodIndex; FoodForm({this.food, this.foodIndex}); @override State<StatefulWidget> createState() { return

问题 I'm trying to read reponse from HTTP in flutter but I didnt read. I posted the request. Can anyone know, what is wrong ? final http.Client client; Future<http.Response> post( Uri uri, { Map<String, dynamic> postParams, String accessToken, }) async { log.info(uri.toString()); log.info('postParams: ${postParams?.toString()}'); ///Encode map to bytes String jsonString = json.encode(postParams); List<int> bodyBytes = utf8.encode(jsonString); Map headers = { HttpHeaders.contentTypeHeader:

问题 I don't understand why this FAB doesn't center it's child. I've tried different things but cannot make it to center perfectly. Because adding for example padding only bottom to the icon could make it center on a Device but maybe not for all. this is my code Theme( data: Theme.of(context).copyWith( highlightColor: Colors.red, splashColor: Colors.red), child: SizedBox( height: MediaQuery.of(context).size.height / 7, width: MediaQuery.of(context).size.height / 7, child: FloatingActionButton(

问题 I use Visual studio code and Andriod studio IDE and different AVD managers but when I run app with Image asset get an error No file or variants found for asset: assets/puffin.jpeg. Simple example: main.dart import 'package:flutter/material.dart'; void main() => runApp(MyApp()); class MyApp extends StatelessWidget { @override Widget build(BuildContext context) { var title = 'Web Images'; return MaterialApp( title: title, home: Scaffold( appBar: AppBar( title: Text(title), ), body: Container(

问题 When i set my tabs to scrollable, it will set all my tabs to the center. But i want to find a way that i can align all the tabs to the left. Is there a way for me align the tabs on the left instead of center? Here is my code. Thank you. class MyApp extends StatelessWidget { // This widget is the root of your application. @override Widget build(BuildContext context) { return MaterialApp( debugShowCheckedModeBanner: false, theme: ThemeData( primarySwatch: colorPrimary, accentColor: colorAccent,

问题 I have a list of users with different portfolios. Each portfolio has the same properties but also a collection of investments. It'd be something like this: Map user = { "name": "John", "portfolios": [ // collection { "title": "My portfolio 1", "investments": [ // collection {"title": "My investment 1.2"}, {"title": "My investment 1.2"} ] }, { "title": "My portfolio 2", "investments": [ // collection {"title": "My investment 2.1"}, {"title": "My investment 2.2"}, {"title": "My investment 2.3"}

问题 final String uid; final firestoreInstance = Firestore.instance; void printData() async{ var firebaseUser = await FirebaseAuth.instance.currentUser(); firestoreInstance.collection("users").document(firebaseUser.uid).get().then((value){ print(value.data); }); } So this function prints to console the retrieved data from firebase firestore when I press the button. But I want to put them into a widget and display them in my app. For ex: Text(printData()) - but it's not allowed. How can I do that?

问题 Closed . This question needs details or clarity. It is not currently accepting answers. Want to improve this question? Add details and clarify the problem by editing this post. Closed 3 months ago . Improve this question Im facing challenge creating a directory with alphabet index. I have List<Map<String, dynamic>> of shops like below: var shops = [ {'name':'Thrifty','products':'cars', 'delivery':'no'}, {'name':'Pizza Express','products':'pizza', 'delivery':'yes'}, {'name':'Fastmart',

问题 I put a slider on a CustomScollView, When I drag the slider, the scrollview will scroll up and down slightly, so my question is When I drag the slider, how to fibidden scroll of the scrollview? This slider is custom slider which extends RenderConstrainedBox class _RenderCupertinoSlider extends RenderConstrainedBox { _RenderCupertinoSlider(){ _drag = new HorizontalDragGestureRecognizer() ..onStart = _handleDragStart ..onUpdate = _handleDragUpdate ..onEnd = _handleDragEnd; }