Android CameraX -手动更改曝光补偿？

dependencies {
    def camerax_version = "1.1.0-alpha07"
    implementation "androidx.camera:camera-camera2:$camerax_version"
    implementation "androidx.camera:camera-lifecycle:$camerax_version"
    implementation "androidx.camera:camera-view:1.0.0-alpha24"
}

val previewConfig = PreviewConfig.Builder().build()
val preview = Preview(previewConfig)

preview.setOnPreviewOutputUpdateListener { previewOutput ->
    // 将预览输出更新到你的UI组件中
    val parent = previewView.parent as ViewGroup
    parent.removeView(previewView)
    parent.addView(previewView, 0)

    previewView.surfaceTexture = previewOutput.surfaceTexture
    updateTransform()
}

val cameraProviderFuture = ProcessCameraProvider.getInstance(context)
cameraProviderFuture.addListener(Runnable {
    val cameraProvider = cameraProviderFuture.get()
    val cameraSelector = CameraSelector.Builder()
        .requireLensFacing(CameraSelector.LENS_FACING_BACK)
        .build()

    cameraProvider.unbindAll()
    cameraProvider.bindToLifecycle(this, cameraSelector, preview)
}, ContextCompat.getMainExecutor(context))

previewView.setOnTouchListener { _, event ->
    if (event.action == MotionEvent.ACTION_DOWN) {
        val factory = previewView.meteringPointFactory
        val point = factory.createPoint(event.x, event.y)
        val action = FocusMeteringAction.Builder(point).build()

        camera?.cameraControl?.startFocusAndMetering(action)
    }
    true
}

// 增加曝光补偿
camera?.cameraControl?.setLinearExposureCompensation(0.5f)

// 减少曝光补偿
camera?.cameraControl?.setLinearExposureCompensation(-0.5f)