onViewFinderTap method
Implementation
void onViewFinderTap(TapDownDetails details, BoxConstraints constraints) {
if (cameraController == null) {
return;
}
//final CameraController cameraController = controller!;
final Offset offset = Offset(
details.localPosition.dx / constraints.maxWidth,
details.localPosition.dy / constraints.maxHeight,
);
cameraController?.setExposurePoint(offset);
cameraController?.setFocusPoint(offset);
}