Description

This change allows developers to implement a reverse duration for a page transition. It defaults to the forward transitionDuration if it isn't specified.

// SAMPLE CLASS: 
class ModifiedReverseTransitionDurationRoute<T> extends MaterialPageRoute<T> {
  ModifiedReverseTransitionDurationRoute({
    @required WidgetBuilder builder,
    RouteSettings settings,
    Duration reverseTransitionDuration,
    bool fullscreenDialog = false,
  }) : _reverseTransitionDuration = reverseTransitionDuration,
       super(
         builder: builder,
         settings: settings,
         fullscreenDialog: fullscreenDialog,
       );

  @override
  Duration get reverseTransitionDuration => _reverseTransitionDuration;
  final Duration _reverseTransitionDuration;
}

// USAGE:
Navigator.of(context).push(
  ModifiedReverseTransitionDurationRoute<dynamic>(
    builder: (BuildContext innerContext) {
      return Container(color: Colors.green);
    },
    reverseTransitionDuration: const Duration(milliseconds: 150), // modified value
  ),
);

Related Issues

n/a

Tests

I added the following tests:

Added a test for the default reverse transition duration
Added a test for a custom reverse transition duration

Checklist

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• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I signed the CLA.
• I read and followed the Flutter Style Guide, including Features we expect every widget to implement.
• I read the Tree Hygiene wiki page, which explains my responsibilities.
• I updated/added relevant documentation (doc comments with ///).
• All existing and new tests are passing.
• The analyzer (flutter analyze --flutter-repo) does not report any problems on my PR.
• I am willing to follow-up on review comments in a timely manner.

Breaking Change

Did any tests fail when you ran them? Please read Handling breaking changes.

• No, no existing tests failed, so this is not a breaking change.
• Yes, this is a breaking change. If not, delete the remainder of this section.
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  • I got input from the developer relations team, specifically from: Replace with the names of who gave advice
  • I wrote a migration guide: Replace with a link to your migration guide