Htykuut

At the moment I have this list

List.generate(72, (index) {

    retrun Container(

        child: new Text('$index'),

    )

})

as the children of a GridView widget. What I however would like to do is return a different value than the $index for certain index values.

For this I have a List that looks like [{index: 2, value: test}{index: 5, value: hello}] with a lot of index/value pairs. So here is the question:

Is there a way now to display the value from the list in the GridView field if the matching index is in the list and if it is not simply return $index?

Just as an example, the field with the index 1 in the GridView should display its index, so it displays 1. The field with the index 2 however should display the matching value from the list, which is test and so on.

It looks like you should preprocess the list into a Map. If necessary, iterate the list adding each entry to a map.

Then you can:

  Map m = <int, String>{

    2: 'test',

    5: 'hello',

  };

  List<Container>.generate(72, (int index) {

    String s = m[index];

    return Container(

      child: Text(s != null ? s : '$index'),

    );

  });

or, more succinctly with the null aware operator

  List<Container>.generate(

    72,

    (int index) => Container(child: Text(m[index] ?? '$index')),

  );