how to get flutter packages code example

Example 1: get package flutter

class Home extends StatelessWidget {
  final controller = Get.put(Controller());
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text("counter")),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            GetBuilder(
                builder: (_) => Text(
                      'clicks: ${controller.count}',
                    )),
            RaisedButton(
              child: Text('Next Route'),
              onPressed: () {
                Get.to(Second());
              },
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
          child: Icon(Icons.add),
          onPressed: controller.increment(),  
          ),
    );
  }
}
class Second extends StatelessWidget {
  final Controller ctrl = Get.find();
  @override
  Widget build(context){
     return Scaffold(body: Center(child: Text("${ctrl.count}")));
  }
}

Example 2: pubspec.yaml flutter

dependencies:
  url_launcher: ^5.4.0    # Good, any 5.4.x version where x >= 0 works.
  image_picker: '5.4.3'   # Not so good, only version 5.4.3 works.