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 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 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 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 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? 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? 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? 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
Dart doc comment escape square brackets Problem Description: I have a simple enum with a doc comment wanting to display [] inside the comment: /// Define the brackets used when displaying a `List` in a cell. /// /// Supported bracket types are: /// * parentheses: () /// * curly: {} /// * square: [] enum … Read more
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