3 posts tagged with "tips"

In this article, we will review how equality works in Dart and Flutter and how the Equatable package can help us to avoid writing a lot of boilerplate code.

We already know that If we want to compare two variables, we can use the == operator. For example, if we want to compare two strings, the code is:

  final car1 = "Toyota";
  final car2 = "Toyota";
  print(car1 == car2); // Result: true

And if we want to compare two numbers, the code is:

  final phone1 = 52123456;
  final phone2 = 52123456;
  print(phone1 == phone2); // Result: true

Do you have a Flutter App, and would you like to show the users when they are offline, like in the next image?

No internet connection banner

Before we start, you can download the source code from GitHub. The source code has examples using: cubit (flutter bloc), getx, ChangeNotifier (provider), and ValueNotifier.

Hay veces que queremos calcular el ancho o la altura de un widget y tomamos como referencia el espacio de pantalla disponible. Por ejemplo en el siguiente fragmento de código, la altura de cada Container es la mitad del tamaño de la pantalla o MediaQuery.of(context).size.height / 2.

Column(
       children: [
          Container(
            color: Colors.blue,
            height: MediaQuery.of(context).size.height / 2,
          ),
          Container(
            color: Colors.green,
            height: MediaQuery.of(context).size.height / 2,
          )
        ],
      )

Como podemos ver cada container ocupa la mitad de la pantalla: