当我使用camerax“1.0.0-alpha06”时,为什么zoomRatio会显示error Unresolved reference?

我读过这篇文章。 https://proandroiddev.com/android-camerax-tap-to-focus-pinch-to-zoom-zoom-slider-eb88f3aa6fc6

我在officecamerx示例中添加了代码A。 https://github.com/android/camera-samples/tree/master/CameraXBasic

示例代码使用camerax“1.0.0-alpha06”

我得到了错误未解决的zoomRatio参考,你可以看到图片1,我如何修复它?

 private fun setUpPinchToZoom() {
        val cameraControl = CameraX.getCameraControl(lensFacing)
        val cameraInfo = CameraX.getCameraInfo(lensFacing)

        val listener = object : ScaleGestureDetector.SimpleOnScaleGestureListener() {
            override fun onScale(detector: ScaleGestureDetector): Boolean {
                val currentZoomRatio: Float = cameraInfo.zoomRatio.value ?: 0F
                val delta = detector.scaleFactor
                cameraControl.setZoomRatio(currentZoomRatio * delta)
                return true
            }
        }

        val scaleGestureDetector = ScaleGestureDetector(context, listener)

        viewFinder.setOnTouchListener { _, event ->
            scaleGestureDetector.onTouchEvent(event)
            return@setOnTouchListener true
        }
    }

图1