What is the correct way to access manually created photos in android?

Question

I'm writing a simple gallery on android using an emulator and right now I'm trying to implement functionality which allows taking a photo right from the app.

I'm saving photo right into /storage/emulated/0/DCIM/Camera/, but the problem is that no application can access newly created photos. I mean that I don't see these photos in Google photos, in the built-in gallery and of course my application.

But I can find these photos using built-in file explorer.

There is a bunch of created photos in /storage/emulated/0/DCIM/Camera/

But, for example, if I create a photo using standart built-in app camera (I've created 3 of them) Google photo sees only them, but not those which I've created within my app.

If I get it right, when I take a photo using standart camera it's saved in /storage/emulated/0/DCIM/Camera/. But why when I create photos in this folder manually they are not discovered by any apps?

Code for taking a photo from my app:

public class TakePhotoActivity extends AppCompatActivity {

    Button takePicBtn;
    ImageView takenImageView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.take_photo);

        takePicBtn = findViewById(R.id.btnTakePic);
        if (Build.VERSION.SDK_INT >= 23){
            requestPermissions(new String[]{Manifest.permission.CAMERA, Manifest.permission.WRITE_EXTERNAL_STORAGE}, 2);
        }
        takePicBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                dispatchTakePictureIntent();
                galleryAddPic();
            }
        });
        takenImageView = findViewById(R.id.takenImage);

    }

        static final int REQUEST_IMAGE_CAPTURE = 1;

        @Override
        protected void onActivityResult ( int requestCode, int resultCode, Intent data){
            super.onActivityResult(requestCode, resultCode, data);
            if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == RESULT_OK) {


                Bitmap bitmap = BitmapFactory.decodeFile(mCurrentPhotoPath);
                takenImageView.setImageBitmap(bitmap);

            }
        }

        String mCurrentPhotoPath;

        private File createImageFile () throws IOException {

            String name = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
            File storageDir = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM), "Camera");

            File image = File.createTempFile(
                    "IMG_" + name,  /* prefix */
                    ".jpeg",         /* suffix */
                    storageDir      /* directory */
            );
            mCurrentPhotoPath = image.getAbsolutePath();
            return image;
        }

        public void dispatchTakePictureIntent () {
            Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
            takePictureIntent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
            takePictureIntent.addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
            if (takePictureIntent.resolveActivity(getPackageManager()) != null) {
                File photoFile = null;
                try {
                    photoFile = createImageFile();
                } catch (IOException ex) {
                    ex.printStackTrace();
                }
                if (photoFile != null) {

                    System.out.println(BuildConfig.APPLICATION_ID  + ".fileprovider");
                    System.out.println(FileProvider.getUriForFile(TakePhotoActivity.this, BuildConfig.APPLICATION_ID  + ".fileprovider", photoFile));


                    takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, FileProvider.getUriForFile(TakePhotoActivity.this, BuildConfig.APPLICATION_ID  + ".fileprovider", photoFile));
                    startActivityForResult(takePictureIntent, REQUEST_IMAGE_CAPTURE);
                }
            }
        }

        private void galleryAddPic () {
            Intent mediaScanIntent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
            mediaScanIntent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
            mediaScanIntent.addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
            File f = new File(mCurrentPhotoPath);
            System.out.println(mCurrentPhotoPath);
            Uri contentUri = FileProvider.getUriForFile(TakePhotoActivity.this, BuildConfig.APPLICATION_ID  + ".fileprovider", f);
            mediaScanIntent.setData(contentUri);
            this.sendBroadcast(mediaScanIntent)
              }
        }
    }

Part of the manifest:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.stpmp">

    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.CAMERA" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    <uses-feature android:name="android.hardware.camera"
        android:required="true" />

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">

        <provider
            android:name="android.support.v4.content.FileProvider"
            android:authorities="${applicationId}.fileprovider"
            android:exported="false"
            android:grantUriPermissions="true">
            <meta-data
                android:name="android.support.FILE_PROVIDER_PATHS"
                android:resource="@xml/file_paths"></meta-data>
        </provider>

file_paths.xml:

<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
    <external-path name="external_files" path="." />
</paths>

Thanks in advance!