Flutter

问题 Everyone I'm using NFC plugin "nfc_in_flutter" in my flutter app but I'm facing "New Tag Scanned" issue in android build. Whenever I scan tag, First time, it works good but on second time automatically/bydefault "New Tag Scanned" activity open. Here is my code: Future<String> _nFCscan() async { String nfcdataString = ""; setState(() { _inAsyncCall = true; }); try { NDEFMessage message = await NFC .readNDEF(once: true, readerMode: NFCDispatchReaderMode()) .timeout(Duration(seconds: 10)) .first

问题 I am using Firebase and keep getting this annoying message when I click on the Sign Up button : flutter: 'package:firebase_auth_platform_interface/src/method_channel/method_channel_user_credential.dart': Failed assertion: line 14 pos 16: 'data != null': is not true. The code works fine. The app is built and run successfully. This happens when I enter my phone, email and password and click on the signup button. My code is: import 'package:flutter/material.dart'; import 'package:firebase_auth

问题 There are many versions of implementation of BLoC pattern. One of them is flutter_bloc by Felix Angelov. On one of the social medias I came across of the statement that flutter_bloc is not a good choice for the project and another BLoC or another state management should be chosen instead . Actually it was a small standard project separated into layers:domain,application,infrastructure and presentation. Nothing special about it. So the guy who complained about the wrong choice was saying that

问题 I load an image on my flutter app like this: Image.asset(imageFilePath, fit: BoxFit.cover) When I run the app on the emulator on the first run I get the following exception: I/flutter ( 7194): ══╡ EXCEPTION CAUGHT BY IMAGE RESOURCE SERVICE ╞════════════════════════════════════════════════════ I/flutter ( 7194): The following assertion was thrown resolving an image codec: I/flutter ( 7194): Unable to load asset: /data/user/0/com.example.myapp/app_flutter/888cba5135c38f7d.jpg ... The image path

问题 I want to build a list view with sticky footer like this article's "Stick to the bottom?!" in Flutter. In CSS, .main-footer{ position: sticky; bottom: 0; } but how to do with Flutter? What I want Scrollable large content Footer (sticky) Scrollable large content 1 and 2 are visible at First (Scrollable content and fixed footer). After scroll to end of 1, Footer (2) become not fixed. Rest of contents (3) will be shown below footer(2). I tried to implement above with CustomScrollView but footer

问题 I want to build a list view with sticky footer like this article's "Stick to the bottom?!" in Flutter. In CSS, .main-footer{ position: sticky; bottom: 0; } but how to do with Flutter? What I want Scrollable large content Footer (sticky) Scrollable large content 1 and 2 are visible at First (Scrollable content and fixed footer). After scroll to end of 1, Footer (2) become not fixed. Rest of contents (3) will be shown below footer(2). I tried to implement above with CustomScrollView but footer

问题 I load an image on my flutter app like this: Image.asset(imageFilePath, fit: BoxFit.cover) When I run the app on the emulator on the first run I get the following exception: I/flutter ( 7194): ══╡ EXCEPTION CAUGHT BY IMAGE RESOURCE SERVICE ╞════════════════════════════════════════════════════ I/flutter ( 7194): The following assertion was thrown resolving an image codec: I/flutter ( 7194): Unable to load asset: /data/user/0/com.example.myapp/app_flutter/888cba5135c38f7d.jpg ... The image path

问题 I have looked at this question on Stack Overflow Flutter getter isn't specified for the class, when it is specified. And I still cannot understand why my class Practice does not have access to the variable _text which is accessed from an element in the List with type TagColumn . class Practice extends StatefulWidget { @override _PracticeState createState() => _PracticeState(); } class _PracticeState extends State<Practice>{ int count = 0; @override Widget build(BuildContext context){ List

问题 I need to know how to check the token at entry point of app. I have already saved that in shared preference by ` _saveToken() async { SharedPreferences prefs = await SharedPreferences.getInstance(); String token = await response.data['token']; await prefs.setString('jwt', token); } ` and I need to bypass my login screen if this jwt is not null. How can I do this? 回答1: You can copy paste run full code below You can get jwt token in main() and check jwt content is null or not in initialRoute

问题 I need to know how to check the token at entry point of app. I have already saved that in shared preference by ` _saveToken() async { SharedPreferences prefs = await SharedPreferences.getInstance(); String token = await response.data['token']; await prefs.setString('jwt', token); } ` and I need to bypass my login screen if this jwt is not null. How can I do this? 回答1: You can copy paste run full code below You can get jwt token in main() and check jwt content is null or not in initialRoute