Flutter icons do not show

Question

I am trying to complete this Flutter Code Lab, but the icons do not appear in my application. But they appears in Android Studio code: I have been included the lib in my file pubspec.yaml

name: startup_namer
description: A new Flutter application.

dependencies:
  flutter:
    sdk: flutter

  cupertino_icons: ^0.1.0
  english_words: ^3.1.0

But result is this:

My main.dart file looks like this:

// Add the heart icons to the ListView.

import 'package:flutter/material.dart';
import 'package:english_words/english_words.dart';


void main() => runApp(new MyApp());

class MyApp extends StatelessWidget {

   ..... 

  Widget _buildRow(WordPair pair) {
    final bool alreadySaved = _saved.contains(pair);

    return new ListTile(
      title: new Text(
        pair.asPascalCase,
        style: _biggerFont,
      ),
      trailing: new Icon(
        alreadySaved ? Icons.favorite : Icons.favorite_border,
        color: alreadySaved ? Colors.red : null,
        size: 22.0,
      ),
      onTap: () {      
        setState(() {
          if (alreadySaved) {
            _saved.remove(pair);
          } else {
            _saved.add(pair);
          }
        });
      },
    );
  }
}

I thought that is because I use iOS emulator, but when I tried with Android emulator the result was the same.

Answer 1

(Copied from the comments)

You need to set uses-material-design: true in pubspec.yaml for the icons to be included in the app.

Answer 2

In my case, I have written uses-material-design: true in pubspec.yaml file. I am able to solve this problem by restarting the Android emulator. You can also try by uninstalling old build from your emulator and then installing the new one.

This is little weird behavior, but it works for me.