I was working on QR code scanner app on iOS where i was getting output AVCaptureOutput
on the delegate method captureOutput:didOutputMetadataObjects:fromConnection:
.
It was working perfectly on swift 3. After I've updated to xcode 9 and swift 4, it stopped working.
Okay I've found an update here.
Found that AVCaptureMetadataOutputObjectsDelegate
method is changed
from
captureOutput(_ captureOutput: AVCaptureOutput!, didOutputMetadataObjects metadataObjects: [Any]!, from connection: AVCaptureConnection!)
to
metadataOutput(_ output: AVCaptureMetadataOutput, didOutput metadataObjects: [AVMetadataObject], from connection: AVCaptureConnection)
After changing this delegate method, its working good now.