CameraX not able to capture a photo

Issue

I added the code from

https://developer.android.com/training/camerax

link . The preview, permissions and everything else is working just fine, however I am not able to capture photo from the button. I declared the button to have a listener and connected the function takePhoto(), but it doesn't seem to work, in the past it works fine and I don't know if it's because of the new version of the CameraX feature is using, I don't know but it doesn't seem to be responding correctly. I have the Logcat open and when I press the button, it has the message that is pressed:

D/ViewRootImpl@70b5dc2[MainActivity]: ViewPostIme pointer 0
D/ViewRootImpl@70b5dc2[MainActivity]: ViewPostIme pointer 1

But that's it really, nothing else but that is my issue at the moment, it's a small issue but I believe I miss something to make this simple issue being resolved and I don't know what it causes to do so. Here is the codes that I will provide below:

Gradle:

plugins {
    id 'com.android.application'
    id 'kotlin-android'
}

android {
    compileSdk 30

    defaultConfig {
        applicationId "com.example.camerax1"
        minSdk 21
        targetSdk 30
        versionCode 1
        versionName "1.0"

        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }
    kotlinOptions {
        jvmTarget = '1.8'
    }
}

dependencies {
    implementation 'androidx.core:core-ktx:1.6.0'
    implementation 'androidx.appcompat:appcompat:1.3.1'
    implementation 'com.google.android.material:material:1.4.0'
    implementation 'androidx.constraintlayout:constraintlayout:2.1.0'
    implementation 'androidx.camera:camera-camera2:1.1.0-alpha08'
    implementation 'androidx.camera:camera-lifecycle:1.1.0-alpha08'
    implementation 'androidx.camera:camera-view:1.0.0-alpha28'
    testImplementation 'junit:junit:4.+'
    androidTestImplementation 'androidx.test.ext:junit:1.1.3'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.4.0'
}

activity_main.xml

<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    tools:context=".MainActivity">

    <androidx.camera.view.PreviewView
        android:id="@+id/previewView"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <Button
        android:id="@+id/captureButton"
        android:layout_width="85dp"
        android:layout_height="85dp"
        android:layout_marginBottom="25dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        android:importantForAccessibility="no" />

</androidx.constraintlayout.widget.ConstraintLayout>

Full code in once class MainActivity.kt

class MainActivity : AppCompatActivity() {
    private var imageCapture: ImageCapture? = null

    private lateinit var outputDirectory: File
    private lateinit var cameraExecutor: ExecutorService

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        //Request camera permissions
        if (allPermissions()) {
            startCamera()
        } else {
            ActivityCompat.requestPermissions(this, REQUIRED_PERMISSIONS, REQUEST_CODE_PERMISSIONS)
        }

        val captureBtn = findViewById<Button>(R.id.captureButton)
        captureBtn.setOnClickListener {
            takePhoto()
        }

        outputDirectory = getOutputDirectory()
        cameraExecutor = Executors.newSingleThreadExecutor()
    }



    private fun takePhoto() {
        Toast.makeText(baseContext, "Processing..", Toast.LENGTH_SHORT).show()
        //Get a stable reference of the modifiable image capture use case
        val imageCapture = imageCapture ?: return

        //Create time-stamped output file to hold the image
        val photoFile = File(
            outputDirectory,
            SimpleDateFormat(FILENAME_FORMAT, Locale.ENGLISH).format(System.currentTimeMillis()) + ".jpg")

        //Create output options object which contains file + metadata
        val outputOptions = ImageCapture.OutputFileOptions.Builder(photoFile).build()

        //Set up image capture listener, which is triggered after photo has been taken
        imageCapture.takePicture(
            outputOptions, ContextCompat.getMainExecutor(this), object : ImageCapture.OnImageSavedCallback {
                override fun onImageSaved(outputFileResults: ImageCapture.OutputFileResults) {
                    val savedUri = Uri.fromFile(photoFile)
                    val msg = "Photo capture succeeded: $savedUri"
                    Toast.makeText(baseContext, msg, Toast.LENGTH_SHORT).show()
                    Log.d(TAG, msg)
                }

                override fun onError(exception: ImageCaptureException) {
                    Log.e(TAG, "Photo capture failed: ${exception.message}", exception)
                }
            }
        )
    }

    private fun startCamera() {
        val viewFiner = findViewById<PreviewView>(R.id.previewView)
        val cameraProviderFuture = ProcessCameraProvider.getInstance(this)

        cameraProviderFuture.addListener({
            //Used to bind the lifecycle of camera to the lifecycle owner
            val cameraProvider: ProcessCameraProvider = cameraProviderFuture.get()

            //Preview
            val preview = Preview.Builder().build().also {
                it.setSurfaceProvider(viewFiner.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(
                    this,
                    cameraSelector,
                    preview
                )
            } catch (exc: Exception) {
                Log.e(TAG, "Use case binding failed", exc)
                Toast.makeText(this, "Use case binding failed: $exc", Toast.LENGTH_SHORT).show()
            }
        }, ContextCompat.getMainExecutor(this))
    }

    private fun allPermissions() = REQUIRED_PERMISSIONS.all {
        ContextCompat.checkSelfPermission(baseContext, it) == PackageManager.PERMISSION_GRANTED
    }

    override fun onRequestPermissionsResult(
        requestCode: Int,
        permissions: Array<out String>,
        grantResults: IntArray
    ) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults)
        if (requestCode == REQUEST_CODE_PERMISSIONS) {
            if (allPermissions()) {
                startCamera()
            } else {
                Toast.makeText(this, "Permissions not granted by the user.", Toast.LENGTH_SHORT).show()
                finish()
            }
        }
    }

    private fun getOutputDirectory(): File {
        val mediaDir = externalMediaDirs.firstOrNull().let {
            File(it, resources.getString(R.string.app_name)).apply { mkdirs() }
        }
        return if (mediaDir.exists())
            mediaDir else filesDir
    }

    override fun onDestroy() {
        super.onDestroy()
        cameraExecutor.shutdown()
    }

    companion object {
        private const val TAG = "CameraXBasic"
        private const val FILENAME_FORMAT = "dd.MM.yyyy - HH:mm:ss"
        private const val REQUEST_CODE_PERMISSIONS = 10
        private val REQUIRED_PERMISSIONS = arrayOf(
            Manifest.permission.CAMERA,
            Manifest.permission.WRITE_EXTERNAL_STORAGE
        )
    }
}

Solution

Your code lacks binding the ImageCapture.Builder() to the camera Provider which is the prominent reason why it is not capturing Images. You need to bind imageCapture builder , it can be done in the following way . In your startCamera() function , you need to bind imageCapture in the following way :

    private fun startCamera() {
        val viewFiner = findViewById<PreviewView>(R.id.previewView)
        val cameraProviderFuture = ProcessCameraProvider.getInstance(this)

        cameraProviderFuture.addListener({
            //Used to bind the lifecycle of camera to the lifecycle owner
            val cameraProvider: ProcessCameraProvider = cameraProviderFuture.get()

            //Preview
            val preview = Preview.Builder().build().also {
                it.setSurfaceProvider(viewFiner.surfaceProvider)
            }

            //set Image Capture Builder
            imageCapture = ImageCapture.Builder()
            .setCaptureMode(ImageCapture.CAPTURE_MODE_MINIMIZE_LATENCY)
            .build()

            //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
               //Add imageCapture to lifecycle 
                cameraProvider.bindToLifecycle(
                    this,
                    cameraSelector,
                    preview,
                    imageCapture
                )
            } catch (exc: Exception) {
                Log.e(TAG, "Use case binding failed", exc)
                Toast.makeText(this, "Use case binding failed: $exc", Toast.LENGTH_SHORT).show()
            }
        }, ContextCompat.getMainExecutor(this))
    }

Answered By - Karunesh Palekar