How to convert a double to an int in Dart?
Round it using the round() method: int calc_ranks(ranks) { double multiplier = .5; return (multiplier * ranks).round(); }
dart
Flutter: Setting the height of the AppBar
You can use PreferredSize: class MyApp extends StatelessWidget { @override Widget build(BuildContext context) { return MaterialApp( title: ‘Example’, home: Scaffold( appBar: PreferredSize( preferredSize: Size.fromHeight(50.0), // here the desired height child: AppBar( // … ) ), body: // … ) ); } }
Enumerate or map through a list with index and value in Dart
There is a asMap method which converts the list to a map where the keys are the index and values are the element at index. Please take a look at the docs here. Example: List _sample = [‘a’,’b’,’c’]; _sample.asMap().forEach((index, value) => f); Hope this helps!
How to Move bottomsheet along with keyboard which has textfield(autofocused is true)?
To fix this issue Add isScrollControlled = true to BottomSheetDialog it’ll allow the bottom sheet to take the full required height which gives more insurance that the keyboard does not cover TextField. Add Keyboard padding using MediaQuery.of(context).viewInsets.bottom Note If your BottomSheetModel is Column make sure you add mainAxisSize: MainAxisSize.min, otherwise the sheet will cover the … Read more
What’s the difference between async and async* in Dart?
Short answer async gives you a Future async* gives you a Stream. async You add the async keyword to a function that does some work that might take a long time. It returns the result wrapped in a Future. Future<int> doSomeLongTask() async { await Future.delayed(const Duration(seconds: 1)); return 42; } You can get that result … Read more
Flutter remove all routes
I was able to accomplish this with the following code: Navigator.of(context) .pushNamedAndRemoveUntil(‘/login’, (Route<dynamic> route) => false); The secret here is using a RoutePredicate that always returns false (Route<dynamic> route) => false. In this situation it removes all of the routes except for the new /login route I pushed.
How to change status bar color in Flutter?
Update Flutter 2.0 (Recommended): On latest Flutter version, you should use: AppBar( systemOverlayStyle: SystemUiOverlayStyle( // Status bar color statusBarColor: Colors.red, // Status bar brightness (optional) statusBarIconBrightness: Brightness.dark, // For Android (dark icons) statusBarBrightness: Brightness.light, // For iOS (dark icons) ), ) Only Android (more flexibility): import ‘package:flutter/services.dart’; void main() { SystemChrome.setSystemUIOverlayStyle(SystemUiOverlayStyle( systemNavigationBarColor: Colors.blue, // navigation … Read more
How does the const constructor actually work?
Const constructor creates a “canonicalized” instance. That is, all constant expressions begin canonicalized, and later these “canonicalized” symbols are used to recognize equivalence of these constants. Canonicalization: A process for converting data that has more than one possible representation into a “standard” canonical representation. This can be done to compare different representations for equivalence, to … Read more
Flutter: RenderBox was not laid out
The problem is that you are placing the ListView inside a Column/Row. The text in the exception gives a good explanation of the error. To avoid the error you need to provide a size to the ListView inside. I propose you this code that uses an Expanded to inform the horizontal size (maximum available) and … Read more
Space between Column’s children in Flutter
You can use Padding widget in between those two widget or wrap those widgets with Padding widget. Update SizedBox widget can be use in between two widget to add space between two widget and it makes code more readable than padding widget. Ex: Column( children: <Widget>[ Widget1(), SizedBox(height: 10), Widget2(), ], ),