interleave 0.1.0

A library that helps to interleave lists, being possible to personalize the steps and offset.

Interleave

A library that helps to interleave lists, being possible to personalize the steps and offset.

---

How to Use

# add this line to your dependencies
interleave: ^0.1.0

import 'package:interleave/interleave.dart';

You can create a instance of Interleave with the following parameters:

property	description	type	default
step	Steps to interleave your items.	int	required
offset	Offset to begin interleaving, if not set, it will be equal step.	int?	same as step
itemLength	Quantity of items	int	required
interleavingItemLength	Quantity of items to interleave	int	required
itemBuilder	Item builder method	Widget (BuildContext, int, int)	required
interleavingItemBuilder	Interleaving item builder method	Widget (BuildContext, int, int)	required

method	description
T item(int index)	Get item at index from a interleaved list
List<T> generate()	Generate a interleaved list

Its also possible to get item and interleaved list with Interleave static methods:

method	description
List<T> Interleave.generateFromList	Generate a interleaved list passing two lists as param
List<T> Interleave.generateFromBuilder	Generate a interleaved list passing item builders as param
T Interleave.itemFromList	Get item at index passing two lists as param
T Interleave.itemFromBuilder	Get item at index passing item builders as param

Usage Examples

Generate a interleaved List<T> calling generate method:

final list = List.generate(10, (index) => index);
final anotherList = List.generate(3, (index) => index);

final interleavedList = Interleave(
  step: 2,
  offset: 3,
  itemLength: list.length,
  interleavingItemLength: anotherList.length,
  itemBuilder: (interleaveIndex, listIndex) {
    return 'a${list[interleaveIndex]}';
  },
  interleavingItemBuilder: (interleaveIndex, listIndex) {
    return 'b${anotherList[interleaveIndex]}';
  },
).generate();
print('list: $interleavedList'); // list: [a0, a1, a2, b0, a3, a4, b1, a5, a6, b2, a7, a8, a9]

Get item from index, calling item method:

final list = List.generate(10, (index) => index);
final anotherList = List.generate(3, (index) => index);

final item = Interleave(
  step: 2,
  offset: 3,
  itemLength: list.length,
  interleavingItemLength: anotherList.length,
  itemBuilder: (interleaveIndex, listIndex) {
    return 'a${list[interleaveIndex]}';
  },
  interleavingItemBuilder: (interleaveIndex, listIndex) {
    return 'b${anotherList[interleaveIndex]}';
  },
).item(3);
print('item: $item'); // item: b0

Interleave.generateFromList:

final list = List.generate(10, (index) => index);
final anotherList = List.generate(3, (index) => index);

final interleavedList = Interleave.generateFromList(
  step: 2,
  offset: 3,
  itemList: list,
  interleavingList: anotherList,
);
print('list: $interleavedList'); // list: [0, 1, 2, 0, 3, 4, 1, 5, 6, 2, 7, 8, 9]

Interleave.generateFromBuilder:

final list = List.generate(10, (index) => index);
final anotherList = List.generate(3, (index) => index);

final interleavedList = Interleave.generateFromBuilder(
  step: 2,
  offset: 3,
  itemLength: list.length,
  interleavingItemLength: anotherList.length,
  itemBuilder: (interleaveIndex, listIndex) {
    return 'a${list[interleaveIndex]}';
  },
  interleavingItemBuilder: (interleaveIndex, listIndex) {
    return 'b${anotherList[interleaveIndex]}';
  },
);
print('list: $interleavedList'); // list: [a0, a1, a2, b0, a3, a4, b1, a5, a6, b2, a7, a8, a9]

Interleave.itemFromList:

final list = List.generate(10, (index) => index);
final anotherList = List.generate(3, (index) => index);

final item = Interleave.itemFromList(
  step: 2,
  offset: 3,
  itemList: list,
  interleavingList: anotherList,
  index: 3,
);
print('item: $item'); // 0

Interleave.itemFromBuilder:

final list = List.generate(10, (index) => index);
final anotherList = List.generate(3, (index) => index);

final item = Interleave.itemFromBuilder(
  step: 2,
  offset: 3,
  itemLength: list.length,
  interleavingItemLength: anotherList.length,
  itemBuilder: (interleaveIndex, listIndex) {
    return 'a${list[interleaveIndex]}';
  },
  interleavingItemBuilder: (interleaveIndex, listIndex) {
    return 'b${anotherList[interleaveIndex]}';
  },
  index: 3,
);
print('item: $item'); // b0