Flutter custom font doesn't change - flutter

Question

I tried to use a custom font for my AppBar, but it didn't change. I tried with two different fonts, RobotoMono and DancingScript, but nothing, the app did't change the font. I tried to unistall the app from the virtual phone too, too create another virtual device, but nothing. That's my main.dart :
import 'package:flutter/material.dart';
import 'background_image_task-9.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Blumax',
debugShowCheckedModeBanner: false,
theme: ThemeData(
fontFamily: 'Dancing',
primarySwatch: myColour
),
home: BackgroundImage(
),
);
}
}
const MaterialColor myColour = const MaterialColor(
0xFF0009FF,
const <int, Color>{
50: const Color(0xFF0009FF),
100: const Color(0xFF0009FF),
200: const Color(0xFF0009FF),
300: const Color(0xFF0009FF),
400: const Color(0xFF0009FF),
500: const Color(0xFF0009FF),
600: const Color(0xFF0009FF),
700: const Color(0xFF0009FF),
800: const Color(0xFF0009FF),
900: const Color(0xFF0009FF),
},
);
This is where i use the custom font, background_image_task-9.dart :
import 'package:flutter/material.dart';
class BackgroundImage extends StatelessWidget{
#override
Widget build(BuildContext context){
return Scaffold(
appBar: AppBar(
elevation: 0,
title: Text('Blumax', style: TextStyle(
fontWeight: FontWeight.w500,
fontFamily: 'RobotoMono',
fontSize: 40
),),
centerTitle: true,
),
body: Container(
decoration: BoxDecoration(
image: DecorationImage(image: AssetImage("assets/blumax.jpg"), fit: BoxFit.cover),
),
),
);
}
}
And that's my pubspec.yaml :
name: iphone_prj
description: A new Flutter project.
version: 1.0.0+1
environment:
sdk: ">=2.1.0 <3.0.0"
dependencies:
flutter:
sdk: flutter
english_words: ^3.1.0
cupertino_icons: ^0.1.2
dev_dependencies:
flutter_test:
sdk: flutter
flutter:
assets:
- assets/
uses-material-design: true
fonts:
- family: RobotoMono
fonts:
- asset: assets/fonts/RobotoMono-Bold.ttf
- family: DancingScript
fonts:
- asset: assets/fonts/DancingScript-Bold.ttf
weight: 300

Answer 1

Just add your font-family name properly in your main ThemeData as per pubspec.yaml file
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Blumax',
debugShowCheckedModeBanner: false,
theme: ThemeData(
fontFamily: 'DancingScript',
primarySwatch: myColour
),
home: BackgroundImage(
),
);
}
}
The problem in your case is your font-family name is DancingScript and your providing it in the ThemeData as Dancing. So it will not effect to your app fonts.
Also, in your BackgroundImage class you have added RobotoMono font. But, the "fontWeight: FontWeight.w500" you have added is not matching as per your pubspec.yaml as you have added there RobotoMono-Bold fonts.
So, by matching your font names and font style will effect your app fonts as per your requirements.

Answer 2

There can be many reasons that avoid changing font in flutter :
1- Notice that the pubsec.yaml file is Space sensitive , It means that you need to use 2 or 4 spaces for declaring blocks. That's why you have to use indentation before declaring fonts. you can see the correct example in the snippet below:
flutter:
fonts:
- family: Raleway
fonts:
- asset: fonts/Raleway-Regular.ttf
- asset: fonts/Raleway-Italic.ttf
style: italic
- family: RobotoMono
fonts:
- asset: fonts/RobotoMono-Regular.ttf
- asset: fonts/RobotoMono-Bold.ttf
weight: 700
2- As the document mentioned the Folder Structure should be like :
awesome_app/
fonts/
Raleway-Regular.ttf
Raleway-Italic.ttf
RobotoMono-Regular.ttf
RobotoMono-Bold.ttf
3- Add your font-family name correctly in your main ThemeData as per pubspec.yaml file:
MaterialApp(
title: 'Custom Fonts',
// Set Raleway as the default app font.
theme: ThemeData(fontFamily: 'Raleway'),
home: MyHomePage(),);

Answer 3

your using asset prefix while declaring fonts in pubspec.yaml
Here is the solution https://stackoverflow.com/a/59113335/5557479