diffutil_dart 0.0.5

Calculate the difference between two lists. Used for implicitly animating Flutter lists without having to maintain a StatefulWidget.

diffutil.dart

Calculate the difference between two lists.

Heavily inspired bei Android's DiffUtil class, the code was adopted for Dart.

Uses Myers algorithm internally.

Usage

Calculating diffs:

Simple usage:

final diffResult = calculateListDiff([1, 2 ,3], [1, 3, 4]);

Custom equality:

final diffResult = calculateListDiff(oldList, newList, (o1, o2) => o1.id == o2.id);

If you don't want to use plain old Dart lists (for example if you're using built_value or kt.dart), and don't want to convert your custom list to standard lists, you can use the calculateDiff function and implement your own DiffDelegate easily.

Using the result:

Implement ListUpdateCallback and call diffResult.dispatchUpdatesTo(myCallback);

Performance metrics:

Same as Android's DiffUtil:

• O(N) space
• O(N + D^2) time performance where D is the length of the edit script.
• additional O(N^2) time where N is the total number of added and removed items if move detection is enabled