I am learning on how to use lookup in Flutter, this is an example that I came across. void main() { Map<List<String>, String> lookup = { ['foo', 'bar']: 'foobar', ['baz', 'qux']: 'bazqux', ['hello', 'world']: 'helloworld', }; List<String> key = ['foo',…
I have a StatelessWidget class : class PopupMenu extends StatelessWidget { final VoidCallback editTaskCallback; const PopupMenu({ required this.editTaskCallback, super.key, }); @override Widget build(BuildContext context) { return PopupMenuButton( itemBuilder:(context) => [ PopupMenuItem( onTap: null, child: TextButton.icon( onPressed: editTaskCallback, icon: const Icon(Icons.edit),…
I try to use Expanded in a DataColumn but I got Incorrect use of ParentDataWidget The idea is, I want to make the text inside the column center. So I code like below: DataColumn( label: Expanded( child: Center( child: Text(…
Please I am having this error in my flutter code. Below is my code: return Scaffold( appBar: AppBar( backgroundColor: Colors.black, leading: IconButton( onPressed: () { Navigator.of(context).pop(); }, icon: const Icon(Icons.arrow_back_ios)), title: const Text('Categories'), ), body: Container( color: Colors.black, height: double.infinity,…
what i want in this code is that the questions to change to the next one in the map whenever the user presses any of the true of false buttons, but the question is not updating even after changing the…
Let's say I have a data class Dog that includes a List of puppies. @immutable class Dog extends Equatable{ final int id; final List<Puppy> listOfPuppies; Dog({required this.id,required this.listOfPuppies}); Dog copyWith({int? newId, List<Puppy>? newListOfPuppies}){ return Dog(id: newId ?? id, listOfPuppies: newListOfPuppies…
At the first time of app opening user will see a pageview. In pageview builder initial value starts from the 0. At first time page opening user will see page index 0. PageView.builder( controller: pageController, itemBuilder: (BuildContext context, int index)…
I have already tried using the --null-safety mode but than my app doesn't work. When I use the debug mode on the emuletor I have no problems. Any idea? Here the error message. flutter build apk Building with sound null…
I'm new using Flutter and and I'm having trouble understanding how the AppBar works. I would like to get a result similar to this my main problem is how to add a box, similar to the orange one in the…
The following RangeError was thrown building: RangeError (index): Invalid value: Only valid value is 0: 1 how can I rectify this error, Can you please tell me what's the issue with my code and how to avoid showing that red…