add a backward variant of BenchCardInfiniteScroll (#58140)
diff --git a/dev/benchmarks/macrobenchmarks/lib/src/web/bench_card_infinite_scroll.dart b/dev/benchmarks/macrobenchmarks/lib/src/web/bench_card_infinite_scroll.dart
index e360268..d83a909 100644
--- a/dev/benchmarks/macrobenchmarks/lib/src/web/bench_card_infinite_scroll.dart
+++ b/dev/benchmarks/macrobenchmarks/lib/src/web/bench_card_infinite_scroll.dart
@@ -11,48 +11,62 @@
/// Creates an infinite list of Material cards and scrolls it.
class BenchCardInfiniteScroll extends WidgetRecorder {
- BenchCardInfiniteScroll() : super(name: benchmarkName);
+ BenchCardInfiniteScroll.forward()
+ : initialOffset = 0.0,
+ finalOffset = 30000.0,
+ super(name: benchmarkName);
+
+ BenchCardInfiniteScroll.backward()
+ : initialOffset = 30000.0,
+ finalOffset = 0.0,
+ super(name: benchmarkNameBackward);
static const String benchmarkName = 'bench_card_infinite_scroll';
+ static const String benchmarkNameBackward = 'bench_card_infinite_scroll_backward';
+
+ final double initialOffset;
+ final double finalOffset;
@override
- Widget createWidget() => const MaterialApp(
- title: 'Infinite Card Scroll Benchmark',
- home: _InfiniteScrollCards(),
- );
+ Widget createWidget() => MaterialApp(
+ title: 'Infinite Card Scroll Benchmark',
+ home: _InfiniteScrollCards(initialOffset, finalOffset),
+ );
}
class _InfiniteScrollCards extends StatefulWidget {
- const _InfiniteScrollCards({Key key}) : super(key: key);
+ const _InfiniteScrollCards(this.initialOffset, this.finalOffset, {Key key}) : super(key: key);
+
+ final double initialOffset;
+ final double finalOffset;
@override
State<_InfiniteScrollCards> createState() => _InfiniteScrollCardsState();
}
class _InfiniteScrollCardsState extends State<_InfiniteScrollCards> {
- ScrollController scrollController;
+ static const Duration stepDuration = Duration(seconds: 20);
+ ScrollController scrollController;
double offset;
- static const double distance = 1000;
- static const Duration stepDuration = Duration(seconds: 1);
@override
void initState() {
super.initState();
- scrollController = ScrollController();
- offset = 0;
+ offset = widget.initialOffset;
+
+ scrollController = ScrollController(
+ initialScrollOffset: offset,
+ );
// Without the timer the animation doesn't begin.
Timer.run(() async {
- while (true) {
- await scrollController.animateTo(
- offset + distance,
- curve: Curves.linear,
- duration: stepDuration,
- );
- offset += distance;
- }
+ await scrollController.animateTo(
+ widget.finalOffset,
+ curve: Curves.linear,
+ duration: stepDuration,
+ );
});
}
@@ -60,13 +74,14 @@
Widget build(BuildContext context) {
return ListView.builder(
controller: scrollController,
+ itemExtent: 100.0,
itemBuilder: (BuildContext context, int index) {
return SizedBox(
height: 100.0,
child: Card(
elevation: 16.0,
child: Text(
- lipsum[index % lipsum.length],
+ '${lipsum[index % lipsum.length]} $index',
textAlign: TextAlign.center,
),
),
diff --git a/dev/benchmarks/macrobenchmarks/lib/web_benchmarks.dart b/dev/benchmarks/macrobenchmarks/lib/web_benchmarks.dart
index 29b0d14..211a446 100644
--- a/dev/benchmarks/macrobenchmarks/lib/web_benchmarks.dart
+++ b/dev/benchmarks/macrobenchmarks/lib/web_benchmarks.dart
@@ -30,7 +30,8 @@
/// When adding a new benchmark, add it to this map. Make sure that the name
/// of your benchmark is unique.
final Map<String, RecorderFactory> benchmarks = <String, RecorderFactory>{
- BenchCardInfiniteScroll.benchmarkName: () => BenchCardInfiniteScroll(),
+ BenchCardInfiniteScroll.benchmarkName: () => BenchCardInfiniteScroll.forward(),
+ BenchCardInfiniteScroll.benchmarkNameBackward: () => BenchCardInfiniteScroll.backward(),
BenchClippedOutPictures.benchmarkName: () => BenchClippedOutPictures(),
BenchDrawRect.benchmarkName: () => BenchDrawRect(),
BenchPathRecording.benchmarkName: () => BenchPathRecording(),
