BarcodeDetector.Builder.setAutoFocusEnabled(true) not working on Nexus 4

[malloth]

In Google Play Services 8.3 CameraSource class you use Camera.setFocusMode("continuous-video").

This mode is invalid for most of the devices on the market (including Nexus 4). It doesn't work in preview mode - ONLY when taking video.

Use Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE or give us an option to set focus mode just like in: https://github.com/googlesamples/android-vision/blob/master/visionSamples/barcode-reader/app/src/main/java/com/google/android/gms/samples/vision/barcodereader/ui/camera/CameraSource.java

[gregkorossy]

Use the setFocusMode(String mode) method instead.

[malloth]

There's no setFocusMode(String mode) method in official CameraSource.Builder according to this link: https://developers.google.com/android/reference/com/google/android/gms/vision/CameraSource.Builder

[pm0733464]

Yes. The official API provides setAutoFocusEnabled instead, which sets the focus mode to FOCUS_MODE_CONTINUOUS_VIDEO.

[malloth]

And that's the problem. Should be FOCUS_MODE_CONTINUOUS_PICTURE instead or new API version should have methods like in visionSamples.

[vpdsouza]

I am seeing the same freaking problem, if I use the VisionSamples which is outdated compare to the latest API version, it works just fine but per the new API it doesn't work. Someone at google please talk to us or update your documentation on how to make the Focus and Flash work with new version of this Barcode API, please.... ???

[irodrigo17]

I'm seeing this same error, did anybody find a solution or a workaround for this?

[Ankurjain30]

Anybody got the solution for this, pls share.

[koroshiya]

I've been having this issue with a number of phones. Some focus just fine, others don't focus at all. I was able to work around this by manipulating the properties of the underlying camera manually after vision has started.

private fun getCamera(cameraSource: CameraSource): Camera? {
        CameraSource::class.java.declaredFields
                .firstOrNull { it.type === Camera::class.java }
                ?.let {
                    it.isAccessible = true
                    try {
                        return it.get(cameraSource) as? Camera?
                    } catch (e: IllegalAccessException) {
                        e.printStackTrace()
                    }
                }

    return null
}

fun setFocus(){
    val delay = TimeUnit.SECONDS.toMillis(1L)
    Handler().postDelayed(delay, null){ //from androidx lib
        try {
            val c2 = getCamera(camera) ?: throw IOException("Camera is null")
            val params = c2.parameters
            params.focusMode = Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE
            c2.parameters = params
        }catch(e: Exception){
            e.printStackTrace()
        }
    }
}

setFocus is called after everything else has been loaded, and the camera has started looking for barcodes.

The postDelayed is because some devices don't seem to set the focus mode if it's too soon after initialization.

Anyway, the above isn't a great solution, but it makes vision usable again on my older test devices. Vision works fine as-is on a Pixel, but not so great on a 5 year old Samsung.