我试图在我的flutter应用程序中整合
CameraX
，但我得到的错误是
Cannot access class 'com.google.common.util.concurrent.ListenableFuture'. Check your module classpath for missing or conflicting dependencies
。
There error comes from below line
val cameraProviderFuture = ProcessCameraProvider.getInstance(context)
以下是我的原生观点
class CealScanQrView(val context: Context, id: Int, creationParams: Map<String?, Any?>?) :
PlatformView {
private var mCameraProvider: ProcessCameraProvider? = null
private var preview: PreviewView
private var linearLayout: LinearLayout = LinearLayout(context)
private lateinit var cameraExecutor: ExecutorService
private lateinit var options: BarcodeScannerOptions
private lateinit var scanner: BarcodeScanner
private var analysisUseCase: ImageAnalysis = ImageAnalysis.Builder()
.build()
companion object {
private val REQUIRED_PERMISSIONS = mutableListOf(Manifest.permission.CAMERA).toTypedArray()
init {
val linearLayoutParams = ViewGroup.LayoutParams(
ViewGroup.LayoutParams.WRAP_CONTENT,
ViewGroup.LayoutParams.WRAP_CONTENT
linearLayout.layoutParams = linearLayoutParams
linearLayout.orientation = LinearLayout.VERTICAL
preview = PreviewView(context)
preview.layoutParams = ViewGroup.LayoutParams(
ViewGroup.LayoutParams.MATCH_PARENT,
ViewGroup.LayoutParams.MATCH_PARENT
linearLayout.addView(preview)
setUpCamera()
private fun setUpCamera(){
if (allPermissionsGranted()) {
startCamera()
cameraExecutor = Executors.newSingleThreadExecutor()
options = BarcodeScannerOptions.Builder()
.setBarcodeFormats(
Barcode.FORMAT_QR_CODE)
.build()
scanner = BarcodeScanning.getClient(options)
analysisUseCase.setAnalyzer(
// newSingleThreadExecutor() will let us perform analysis on a single worker thread
Executors.newSingleThreadExecutor()
) { imageProxy ->
processImageProxy(scanner, imageProxy)
override fun getView(): View {
return linearLayout
override fun dispose() {
cameraExecutor.shutdown()
@SuppressLint("UnsafeOptInUsageError")
private fun processImageProxy(
barcodeScanner: BarcodeScanner,
imageProxy: ImageProxy
imageProxy.image?.let { image ->
val inputImage =
InputImage.fromMediaImage(
image,
imageProxy.imageInfo.rotationDegrees
barcodeScanner.process(inputImage)
.addOnSuccessListener { barcodeList ->
val barcode = barcodeList.getOrNull(0)
// `rawValue` is the decoded value of the barcode
barcode?.rawValue?.let { value ->
mCameraProvider?.unbindAll()
.addOnFailureListener {
// This failure will happen if the barcode scanning model
// fails to download from Google Play Services
.addOnCompleteListener {
// When the image is from CameraX analysis use case, must
// call image.close() on received images when finished
// using them. Otherwise, new images may not be received
// or the camera may stall.
imageProxy.image?.close()
imageProxy.close()
private fun allPermissionsGranted() = REQUIRED_PERMISSIONS.all {
ContextCompat.checkSelfPermission(context, it) == PackageManager.PERMISSION_GRANTED
private fun startCamera() {
val cameraProviderFuture = ProcessCameraProvider.getInstance(context)
cameraProviderFuture.addListener({
// Used to bind the lifecycle of cameras to the lifecycle owner
val cameraProvider: ProcessCameraProvider = cameraProviderFuture.get()
mCameraProvider = cameraProvider
// Preview
val surfacePreview = Preview.Builder()
.build()
.also {
it.setSurfaceProvider(preview.surfaceProvider)
// Select back camera as a default
val cameraSelector = CameraSelector.DEFAULT_BACK_CAMERA
try {
// Unbind use cases before rebinding
cameraProvider.unbindAll()
// Bind use cases to camera
cameraProvider.bindToLifecycle(
(context as FlutterActivity),
cameraSelector,
surfacePreview,
analysisUseCase,
} catch (exc: Exception) {
// Do nothing on exception
}, ContextCompat.getMainExecutor(context))
class CealScanQrViewFactory : PlatformViewFactory(StandardMessageCodec.INSTANCE) {
override fun create(context: Context, viewId: Int, args: Any?): PlatformView {
val creationParams = args as Map<String?, Any?>?
return CealScanQrView(context, viewId, creationParams)