Get iteration index from List.map()

Can also try this:


list.asMap().keys.toList().map((index) {
// var item = list[index];
// index is the index of each element.
return youFunction(index);
});



I also write other approaches as well in my blog here.

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its pretty simple and straight forward in dart.

myList.map((item) =>
print(myList.indexOf(item));//here I printing index
).toList()

You can simply use the `mapIndexed` method:


```
userBoard.mapIndexed(
(int index, element) => Container( ... ))
.toList();
```

This is one of the many extensions from the FIC package:

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---

If you don't want to add a package to your project you can just copy the extension itself:


```
extension FicListExtension<T> on List<T> {

/// Maps each element of the list.
/// The [map] function gets both the original [item] and its [index].
Iterable<E> mapIndexed<E>(E Function(int index, T item) map) sync* {
for (var index = 0; index < length; index++) {
yield map(index, this[index]);
}
}
}
```

_Note: I'm one of the authors of that package._

---

**Update:** I have now removed a few methods, like `Iterable.mapIndexed()` from the [FIC package][1], because Google added a similar method to their [collection package][2], and I want both packages to be compatible.


[1]:

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[2]:

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:collection/collection.dart

Dart has released the [`collection`](

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) package that comes with a [`mapIndexed`](

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) extension to all Iterables.

```dart
import 'package:collection/collection.dart';

void main() {
final fruitList = ['apple', 'orange', 'mango'];
final withIndices = fruitList.mapIndexed((index, fruit) => "$index - $fruit");
print(withIndices);
}
```
([DartPad](

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))

The package comes with all sorts of handy extensions and useful tools to work with collections.

You can use asMap() and entries.map() to get the index.

```dart
list.asMap().entries.map((e) {
var index = e.key;
var value = e.value;
// ...
}
```

The current version of built-in [collection package][1] now contains the method `mapIndexed` and comprehensive set of other `List`/`Iterable` [extension methods][2].

```dart
import 'package:collection/collection.dart';
```


[1]:

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[2]:

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```
Map map = {
'1st':'first',
'2nd':'second'}; //any data

List mapAsList = map.keys.toList(); //convert map to list to get iteration index

print( map[mapAsList[0]] ); //first
print( map[mapAsList[1]] ); //second
```

Try this: [source][1]
--------
(Key in map) same (index in list)

myList.asMap().entries.map((entry) {
int idx = entry.key;
String val = entry.value;

return something;
}


[1]:

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To get access to index, you need to convert your list to a map using the [asMap][1] operator.

**Example**

final fruitList = ['apple', 'orange', 'mango'];
final fruitMap = fruitList.asMap(); // {0: 'apple', 1: 'orange', 2: 'mango'}

// To access 'orange' use the index 1.
final myFruit = fruitMap[1] // 'orange'

// To convert back to list
final fruitListAgain = fruitMap.values.toList();

**Your Code**

userBoard.asMap().map((i, element) => MapEntry(i, Stack(
GestureDetector(onTap: () {
setState(() {
// print("element=${element.toString()}");
// print("element=${userBoard[i].toString()}");
});
}),
))).values.toList();

**References to other answers**
- I like [this answer][2] better. Please take a look.
- If you want in multiple places try extending [like this][3].
- Alternatively, you could also try the [dart collection approach][4].


[1]:

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[2]:

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[3]:

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[4]:

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You can do it by defining a variable named index:

```js
Widget listWidget() {

List < String > myList = ['A', 'B', 'C'];

int index = -1;

return Column(
children: myList.map < Widget > ((element) {
index++;
return Container(
Text("$index : $element")
);
}).toList()
);
}
```