Remove assert from Image._handleImageFrame() (#33602)
Tickers being disabled and re-enabled can cause the
condition of a synchronous notification happening after
image frames have been delivered, which is valid in that
case. As such, this removes the assert.
https://github.com/flutter/flutter/issues/32374
diff --git a/packages/flutter/lib/src/widgets/image.dart b/packages/flutter/lib/src/widgets/image.dart
index e6ae97d..c77645f 100644
--- a/packages/flutter/lib/src/widgets/image.dart
+++ b/packages/flutter/lib/src/widgets/image.dart
@@ -936,7 +936,6 @@
}
void _handleImageFrame(ImageInfo imageInfo, bool synchronousCall) {
- assert(_frameNumber == null || !synchronousCall);
setState(() {
_imageInfo = imageInfo;
_loadingProgress = null;
diff --git a/packages/flutter/test/widgets/image_test.dart b/packages/flutter/test/widgets/image_test.dart
index 93fb6a5..290a959 100644
--- a/packages/flutter/test/widgets/image_test.dart
+++ b/packages/flutter/test/widgets/image_test.dart
@@ -844,12 +844,12 @@
expect(lastFrame, isNull);
expect(find.byType(Center), findsOneWidget);
expect(find.byType(RawImage), findsOneWidget);
- streamCompleter.notifyListeners(imageInfo: ImageInfo(image: await nextFrame()));
+ streamCompleter.setData(imageInfo: ImageInfo(image: await nextFrame()));
await tester.pump();
expect(lastFrame, 0);
expect(find.byType(Center), findsOneWidget);
expect(find.byType(RawImage), findsOneWidget);
- streamCompleter.notifyListeners(imageInfo: ImageInfo(image: await nextFrame()));
+ streamCompleter.setData(imageInfo: ImageInfo(image: await nextFrame()));
await tester.pump();
expect(lastFrame, 1);
expect(find.byType(Center), findsOneWidget);
@@ -877,7 +877,7 @@
expect(lastFrame, isNull);
expect(lastFrameWasSync, isFalse);
expect(find.byType(RawImage), findsOneWidget);
- streamCompleter.notifyListeners(imageInfo: ImageInfo(image: image));
+ streamCompleter.setData(imageInfo: ImageInfo(image: image));
await tester.pump();
expect(lastFrame, 0);
expect(lastFrameWasSync, isFalse);
@@ -904,7 +904,7 @@
expect(lastFrame, 0);
expect(lastFrameWasSync, isTrue);
expect(find.byType(RawImage), findsOneWidget);
- streamCompleter.notifyListeners(imageInfo: ImageInfo(image: image));
+ streamCompleter.setData(imageInfo: ImageInfo(image: image));
await tester.pump();
expect(lastFrame, 1);
expect(lastFrameWasSync, isTrue);
@@ -942,6 +942,79 @@
expect(tester.state(find.byType(Image)), same(state));
});
+ testWidgets('Image state handles enabling and disabling of tickers', (WidgetTester tester) async {
+ final ui.Codec codec = await tester.runAsync(() {
+ return ui.instantiateImageCodec(Uint8List.fromList(kAnimatedGif));
+ });
+
+ Future<ui.Image> nextFrame() async {
+ final ui.FrameInfo frameInfo = await tester.runAsync(codec.getNextFrame);
+ return frameInfo.image;
+ }
+
+ final TestImageStreamCompleter streamCompleter = TestImageStreamCompleter();
+ final TestImageProvider imageProvider = TestImageProvider(streamCompleter: streamCompleter);
+ int lastFrame;
+ int buildCount = 0;
+
+ Widget buildFrame(BuildContext context, Widget child, int frame, bool wasSynchronouslyLoaded) {
+ lastFrame = frame;
+ buildCount++;
+ return child;
+ }
+
+ await tester.pumpWidget(
+ TickerMode(
+ enabled: true,
+ child: Image(
+ image: imageProvider,
+ frameBuilder: buildFrame,
+ ),
+ ),
+ );
+
+ final State<Image> state = tester.state(find.byType(Image));
+ expect(lastFrame, isNull);
+ expect(buildCount, 1);
+ streamCompleter.setData(imageInfo: ImageInfo(image: await nextFrame()));
+ await tester.pump();
+ expect(lastFrame, 0);
+ expect(buildCount, 2);
+
+ await tester.pumpWidget(
+ TickerMode(
+ enabled: false,
+ child: Image(
+ image: imageProvider,
+ frameBuilder: buildFrame,
+ ),
+ ),
+ );
+
+ expect(tester.state(find.byType(Image)), same(state));
+ expect(lastFrame, 0);
+ expect(buildCount, 3);
+ streamCompleter.setData(imageInfo: ImageInfo(image: await nextFrame()));
+ streamCompleter.setData(imageInfo: ImageInfo(image: await nextFrame()));
+ await tester.pump();
+ expect(lastFrame, 0);
+ expect(buildCount, 3);
+
+ await tester.pumpWidget(
+ TickerMode(
+ enabled: true,
+ child: Image(
+ image: imageProvider,
+ frameBuilder: buildFrame,
+ ),
+ ),
+ );
+
+ expect(tester.state(find.byType(Image)), same(state));
+ expect(lastFrame, 1); // missed a frame because we weren't animating at the time
+ expect(buildCount, 4);
+ });
+
testWidgets('Image invokes loadingBuilder on chunk event notification', (WidgetTester tester) async {
final ui.Image image = await tester.runAsync(createTestImage);
final TestImageStreamCompleter streamCompleter = TestImageStreamCompleter();
@@ -966,19 +1039,19 @@
expect(chunkEvents.length, 1);
expect(chunkEvents.first, isNull);
expect(tester.binding.hasScheduledFrame, isFalse);
- streamCompleter.notifyListeners(chunkEvent: const ImageChunkEvent(cumulativeBytesLoaded: 10, expectedTotalBytes: 100));
+ streamCompleter.setData(chunkEvent: const ImageChunkEvent(cumulativeBytesLoaded: 10, expectedTotalBytes: 100));
expect(tester.binding.hasScheduledFrame, isTrue);
await tester.pump();
expect(chunkEvents.length, 2);
expect(find.text('loading 10 / 100'), findsOneWidget);
expect(find.byType(RawImage), findsNothing);
- streamCompleter.notifyListeners(chunkEvent: const ImageChunkEvent(cumulativeBytesLoaded: 30, expectedTotalBytes: 100));
+ streamCompleter.setData(chunkEvent: const ImageChunkEvent(cumulativeBytesLoaded: 30, expectedTotalBytes: 100));
expect(tester.binding.hasScheduledFrame, isTrue);
await tester.pump();
expect(chunkEvents.length, 3);
expect(find.text('loading 30 / 100'), findsOneWidget);
expect(find.byType(RawImage), findsNothing);
- streamCompleter.notifyListeners(imageInfo: ImageInfo(image: image));
+ streamCompleter.setData(imageInfo: ImageInfo(image: image));
await tester.pump();
expect(chunkEvents.length, 4);
expect(find.byType(Text), findsNothing);
@@ -998,12 +1071,12 @@
);
expect(tester.binding.hasScheduledFrame, isFalse);
- streamCompleter.notifyListeners(chunkEvent: const ImageChunkEvent(cumulativeBytesLoaded: 10, expectedTotalBytes: 100));
+ streamCompleter.setData(chunkEvent: const ImageChunkEvent(cumulativeBytesLoaded: 10, expectedTotalBytes: 100));
expect(tester.binding.hasScheduledFrame, isFalse);
- streamCompleter.notifyListeners(imageInfo: ImageInfo(image: image));
+ streamCompleter.setData(imageInfo: ImageInfo(image: image));
expect(tester.binding.hasScheduledFrame, isTrue);
await tester.pump();
- streamCompleter.notifyListeners(chunkEvent: const ImageChunkEvent(cumulativeBytesLoaded: 10, expectedTotalBytes: 100));
+ streamCompleter.setData(chunkEvent: const ImageChunkEvent(cumulativeBytesLoaded: 10, expectedTotalBytes: 100));
expect(tester.binding.hasScheduledFrame, isFalse);
expect(find.byType(RawImage), findsOneWidget);
});
@@ -1029,7 +1102,7 @@
expect(find.byType(Padding), findsOneWidget);
expect(find.byType(RawImage), findsOneWidget);
expect(tester.widget<Padding>(find.byType(Padding)).child, isInstanceOf<RawImage>());
- streamCompleter.notifyListeners(chunkEvent: const ImageChunkEvent(cumulativeBytesLoaded: 10, expectedTotalBytes: 100));
+ streamCompleter.setData(chunkEvent: const ImageChunkEvent(cumulativeBytesLoaded: 10, expectedTotalBytes: 100));
await tester.pump();
expect(find.byType(Center), findsOneWidget);
expect(find.byType(Padding), findsOneWidget);
@@ -1047,7 +1120,7 @@
);
expect(find.byType(RawImage), findsOneWidget);
- streamCompleter.notifyListeners(chunkEvent: const ImageChunkEvent(cumulativeBytesLoaded: 10, expectedTotalBytes: 100));
+ streamCompleter.setData(chunkEvent: const ImageChunkEvent(cumulativeBytesLoaded: 10, expectedTotalBytes: 100));
expect(tester.binding.hasScheduledFrame, isFalse);
final State<Image> state = tester.state(find.byType(Image));
@@ -1063,7 +1136,7 @@
expect(find.byType(Center), findsOneWidget);
expect(find.byType(RawImage), findsOneWidget);
expect(tester.state(find.byType(Image)), same(state));
- streamCompleter.notifyListeners(chunkEvent: const ImageChunkEvent(cumulativeBytesLoaded: 10, expectedTotalBytes: 100));
+ streamCompleter.setData(chunkEvent: const ImageChunkEvent(cumulativeBytesLoaded: 10, expectedTotalBytes: 100));
expect(tester.binding.hasScheduledFrame, isTrue);
await tester.pump();
expect(find.byType(Center), findsOneWidget);
@@ -1085,7 +1158,7 @@
expect(find.byType(Center), findsOneWidget);
expect(find.byType(RawImage), findsOneWidget);
- streamCompleter.notifyListeners(chunkEvent: const ImageChunkEvent(cumulativeBytesLoaded: 10, expectedTotalBytes: 100));
+ streamCompleter.setData(chunkEvent: const ImageChunkEvent(cumulativeBytesLoaded: 10, expectedTotalBytes: 100));
expect(tester.binding.hasScheduledFrame, isTrue);
await tester.pump();
expect(find.byType(Center), findsOneWidget);
@@ -1099,7 +1172,7 @@
expect(find.byType(Center), findsNothing);
expect(find.byType(RawImage), findsOneWidget);
expect(tester.state(find.byType(Image)), same(state));
- streamCompleter.notifyListeners(chunkEvent: const ImageChunkEvent(cumulativeBytesLoaded: 10, expectedTotalBytes: 100));
+ streamCompleter.setData(chunkEvent: const ImageChunkEvent(cumulativeBytesLoaded: 10, expectedTotalBytes: 100));
expect(tester.binding.hasScheduledFrame, isFalse);
});
}
@@ -1141,16 +1214,17 @@
}
class TestImageStreamCompleter extends ImageStreamCompleter {
- TestImageStreamCompleter([this.synchronousImage]);
+ TestImageStreamCompleter([this._currentImage]);
- final ImageInfo synchronousImage;
+ ImageInfo _currentImage;
final Set<ImageStreamListener> listeners = <ImageStreamListener>{};
@override
void addListener(ImageStreamListener listener) {
listeners.add(listener);
- if (synchronousImage != null)
- listener.onImage(synchronousImage, true);
+ if (_currentImage != null) {
+ listener.onImage(_currentImage, true);
+ }
}
@override
@@ -1158,10 +1232,13 @@
listeners.remove(listener);
}
- void notifyListeners({
+ void setData({
ImageInfo imageInfo,
ImageChunkEvent chunkEvent,
}) {
+ if (imageInfo != null) {
+ _currentImage = imageInfo;
+ }
final List<ImageStreamListener> localListeners = listeners.toList();
for (ImageStreamListener listener in localListeners) {
if (imageInfo != null) {
