captureImage method
Implementation
void captureImage(Function(CaptureResult) onCapture) async {
WidgetsBinding.instance!.addPostFrameCallback((_) async {
final boundary = _boundaryKey.currentContext!.findRenderObject()
as RenderRepaintBoundary;
final image = await boundary.toImage(pixelRatio: 2);
final data = await image.toByteData(format: ImageByteFormat.png);
onCapture(
CaptureResult(data!.buffer.asUint8List(), image.width, image.height));
});
}