Why enums can't be used in const constructors in Flutter?

Why enums can't be used in const constructors in Flutter? Problem Description: can someone tell me if there’s a way to use enhanced enums in const constructors? I tried both named constructors and factory constructors, with no luck: enum MyEnum { first(‘first-string’), second(‘second-string’); final String string; const MyEnum(this.string); } class MyClass { final String input; … Read more

'canGoBack' method isn't defined for flutter WebViewPlus

'canGoBack' method isn't defined for flutter WebViewPlus Problem Description: I’m trying to use ( canGoBack() ) method with (flutter webview plus) plugin but it isn’t work!! vs code said: The method ‘canGoBack’ isn’t defined for the type ‘WebViewPlusController’. Try correcting the name to the name of an existing method, or defining a method named ‘canGoBack’. … Read more

Flutter Firebase UI not updating and showing correct user info after signing out and in with different user

Flutter Firebase UI not updating and showing correct user info after signing out and in with different user Problem Description: I’m creating and testing a simple dashboard that I want to display the current user’s email. I’m just using [email protected] and [email protected]. When I signout of test1 and sign in with test2, my UI still … Read more

Flutter Firebase UI not updating and showing correct user info after signing out and in with different user

Flutter Firebase UI not updating and showing correct user info after signing out and in with different user Problem Description: I’m creating and testing a simple dashboard that I want to display the current user’s email. I’m just using [email protected] and [email protected]. When I signout of test1 and sign in with test2, my UI still … Read more

Flutter Error : Unhandled Exception: RangeError (index): Invalid value: Valid value range is empty: 0

Flutter Error : Unhandled Exception: RangeError (index): Invalid value: Valid value range is empty: 0 Problem Description: I am trying to fetch data from an API, and although data is fetched for a hardcoded request, I am unable to get it dynamically. It gives the following error: E/flutter (11813): [ERROR:flutter/runtime/dart_vm_initializer.cc(41)] Unhandled Exception: RangeError (index): Invalid … Read more

How can I get the last uploaded data to Firebase?

How can I get the last uploaded data to Firebase? Problem Description: StreamBuilder<QuerySnapshot<Map<String, dynamic>>>( stream: FirebaseFirestore.instance .collection(‘users’) .where(‘bmi’) .limit(1) .snapshots(), }, )), class User { final double bmi; User( {required this.bmi}); Map<String, dynamic> toJson() => { ‘bmi’: bmi, }; static User fromJson(Map<String, dynamic> json) => User( bmi: json[‘bmi’]); } I want to pull the last … Read more

Why cant I use .sum in a Stateful Widget?

Why cant I use .sum in a Stateful Widget? Problem Description: I have built out a stateless widget that I now need to change to a stateful widget. Within my stateless widget, I have a function… SumOfRoundedTankValue() { List<double> numbers = []; port.ports.tankSpecs.forEach((e) { numbers.add(double.parse(e.defUsGallons)); }); final sum = numbers.sum; return (sum); } Why does … Read more

(Dart) How can I create a sub list of only certain items in the first list containing a string?

(Dart) How can I create a sub list of only certain items in the first list containing a string? Problem Description: Here is my are my List Items: static List<Category> getMockedCategories(){ return[ Category( name: "Ascent", imgName: "AscentLoading", subCategories: [ SubCategory( name: "ascent", imgName: "ascent_a_sova_frontgen" ) ] ), Category( name: "Breeze", imgName: "BreezeLoading", subCategories: [ ] … Read more

TextFormFied validate spacing

TextFormFied validate spacing Problem Description: I have TextFormField widget with username TextFormField( controller: usernameController, validator: (value) { if (value!.isEmpty) { return ‘username is empty’; } if (value.length <= 4) { return ‘passord id too short, min 4 characters’; } return null; }, decoration: const InputDecoration( hintText: ‘username’, border: OutlineInputBorder( borderSide: BorderSide(color: Colors.black))), ), But I … Read more

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