Throttling keyboard events until child widget is updated - flutter

Question

In my simple Flutter desktop image browser I use arrow keys for traversing items in a folder (actually ZIP archive). As loading large images is slower, if arrow keys are pressed multiple times until the image is fully loaded, some images are skipped.
I'd rather waited for all images until fully loaded and to queue key events to some limit (e.g. up to 5 key events).
The actual core snippets:
#override
Widget build(BuildContext context) {
return Scaffold(
backgroundColor: Colors.black,
body: RawKeyboardListener(
focusNode: focusNode,
autofocus: true,
onKey: handleKey,
child: InteractiveViewer(
child: image,
),
),
);
}
void handleKey(RawKeyEvent keyEvent) async {
if (keyEvent.isKeyPressed(LogicalKeyboardKey.arrowLeft) ||
keyEvent.isKeyPressed(LogicalKeyboardKey.arrowRight) ||
keyEvent.isKeyPressed(LogicalKeyboardKey.home) ||
keyEvent.isKeyPressed(LogicalKeyboardKey.end)) {
int newImageIndex = currentImageIndex;
if (keyEvent.isKeyPressed(LogicalKeyboardKey.arrowLeft)) {
newImageIndex = max(currentImageIndex - 1, 0);
} else if (keyEvent.isKeyPressed(LogicalKeyboardKey.arrowRight)) {
newImageIndex = min(currentImageIndex + 1, widget.fileNameMap.length - 1);
}
if (newImageIndex != currentImageIndex) {
updateImage(newImageIndex);
}
}
void updateImage(int index) {
setState(() {
File file = new File(paths[index]);
image = new Image.file(file);
});
}

Answer 1

I've found that image skipping on subsequent key pressing can be avoided when the image widget is updated after image data is fully loaded, which can be achieved by ImageProvider this way:
void updateImage(int index) {
File file = new File(paths[index]);
var imageData = new FileImage(file);
imageData
.resolve(ImageConfiguration())
.addListener(ImageStreamListener((ImageInfo _, bool __) {
if (mounted) {
setState(() {
image = new Image(image: imageData);
});
}
}));
}`