How to use conditional statement within child attribute of a Flutter Widget (Center Widget)

Question

So far whenever I needed to use a conditional statement within a Widget I have done the following (Using Center and Containers as simplified dummy examples):

Answer 1

I found out that an easy way to use conditional logic to build Flutter UI is to keep the logic outside of the UI. Here is a function to return two different colors:

Color getColor(int selector) {
  if (selector % 2 == 0) {
    return Colors.blue;
  } else {
    return Colors.blueGrey;
  }
}

The function is used below to to set the background of the CircleAvatar.

new ListView.builder(
  itemCount: users.length,
  itemBuilder: (BuildContext context, int index) {
    return new Column(
      children: [
        new ListTile(
          leading: new CircleAvatar(
            backgroundColor: getColor(index),
            child: new Text(users[index].name[0])
          ),
          title: new Text(users[index].login),
          subtitle: new Text(users[index].name),
        ),
        new Divider(height: 2.0),
      ],
    );
  },
);

Very neat as you can reuse your color selector function in several widgets.