Code capable of opening a file chooser from a Webview in Android

FileChooserActivity.java

public class AgregarItemActivity extends AppCompatActivity {

    Usuario user;

    boolean listenerStatus;
    String sessionID;
    String eventoID;
    String agregarItemURL;
    String agregarImagenesURL;
    String item;
    String itemDetalle;
    ProgressDialog pd;

    int fotoTomada;
    boolean vistaImagenesCargada;
    ItemMercaderia nuevoItem;
    LinkedList<InfoItemMercaderia>infoItem;
    
    ValueCallback<Uri[]> recentUploadMessage;

    SharedPreferences preferencias;

    /** File chooser attributes */
    private static final int INPUT_FILE_REQUEST_CODE = 1;
    private static final int FILECHOOSER_RESULTCODE = 1;
    private static final String TAG = AgregarItemActivity.class.getSimpleName();
    private WebView myWebView;
    private WebSettings webSettings;
    private ValueCallback<Uri> mUploadMessage;
    private Uri mCapturedImageURI = null;
    private ValueCallback<Uri[]> mFilePathCallback;
    private String mCameraPhotoPath;

    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
            if (requestCode != INPUT_FILE_REQUEST_CODE || mFilePathCallback == null) {
                super.onActivityResult(requestCode, resultCode, data);
                return;
            }
            Uri[] results = null;
            // Check that the response is a good one
            if (resultCode == Activity.RESULT_OK) {
                if (data == null) {
                    // If there is not data, then we may have taken a photo
                    if (mCameraPhotoPath != null) {
                        results = new Uri[]{Uri.parse(mCameraPhotoPath)};
                    }
                } else {
                    String dataString = data.getDataString();
                    if (dataString != null) {
                        results = new Uri[]{Uri.parse(dataString)};
                    }
                }
            }
            mFilePathCallback.onReceiveValue(results);
            mFilePathCallback = null;
        } else if (Build.VERSION.SDK_INT <= Build.VERSION_CODES.KITKAT) {
            if (requestCode != FILECHOOSER_RESULTCODE || mUploadMessage == null) {
                super.onActivityResult(requestCode, resultCode, data);
                return;
            }
            if (requestCode == FILECHOOSER_RESULTCODE) {
                if (null == this.mUploadMessage) {
                    return;
                }
                Uri result = null;
                try {
                    if (resultCode != RESULT_OK) {
                        result = null;
                    } else {
                        // retrieve from the private variable if the intent is null
                        result = data == null ? mCapturedImageURI : data.getData();
                    }
                } catch (Exception e) {
                    Toast.makeText(getApplicationContext(), "activity :" + e,
                            Toast.LENGTH_LONG).show();
                }
                mUploadMessage.onReceiveValue(result);
                mUploadMessage = null;
            }
        }
        return;
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        /***/
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_agregar_item);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);

        myWebView = (WebView) this.findViewById(R.id.agregar_item_webview);

        webSettings = myWebView.getSettings();
        webSettings.setJavaScriptEnabled(true);
        webSettings.setAllowContentAccess(true);
        webSettings.setLoadWithOverviewMode(true);
        webSettings.setAllowFileAccess(true);
        webSettings.setAllowUniversalAccessFromFileURLs(true);
        webSettings.setAllowContentAccess(true);
        webSettings.setAllowFileAccessFromFileURLs(true);
        webSettings.setDomStorageEnabled(true);
        myWebView.addJavascriptInterface(new WebAppInterface(this), "Android");

        if (Build.VERSION.SDK_INT >= 19) {
            myWebView.setLayerType(View.LAYER_TYPE_HARDWARE, null);
        }
        else if(Build.VERSION.SDK_INT >=11 && Build.VERSION.SDK_INT < 19) {
            myWebView.setLayerType(View.LAYER_TYPE_SOFTWARE, null);
        }
        /***/
        myWebView.setWebViewClient(new WebViewClient() {
            @Override
            public void onPageStarted(WebView view, String url, Bitmap favicon) {
                pd.show();
                super.onPageStarted(view, url, favicon);
            }

            @Override
            public void onPageFinished(WebView view, String url) {
                super.onPageFinished(view, url);
                pd.dismiss();
                if(vistaImagenesCargada) {
                    Permisos.verifyStoragePermissions(AgregarItemActivity.this);
                }
            }

            @SuppressWarnings("deprecation")
            @Override
            public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
                super.onReceivedError(view, errorCode, description, failingUrl);
                view.loadUrl("about:blank");
                AlertDialog.Builder builder = new AlertDialog.Builder(AgregarItemActivity.this);
                builder.setMessage("Hubo un problema la cargar el formulario")
                        //builder.setMessage(description)
                        .setTitle("Error")
                        .setPositiveButton("aceptar", new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {
                                finish();
                            }
                        }).show();
            }
            @Override
            public void onReceivedError(WebView view, WebResourceRequest request, WebResourceError error) {
                view.loadUrl("about:blank");
                AlertDialog.Builder builder = new AlertDialog.Builder(AgregarItemActivity.this);
                builder.setMessage("Hubo un problema la cargar el formulario")
                        //builder.setMessage(error.toString())
                        .setTitle("Error")
                        .setPositiveButton("aceptar", new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {
                                finish();
                            }
                        }).show();
            }


        });

        myWebView.setWebChromeClient(new ChromeClient());

        user = UtilsViews.usuarioSession(this);
        eventoID = UtilsViews.crearEventoID(user.getIdUsuario(), this);
        pd = UtilsViews.cargaPB("Obteniendo Formulario", AgregarItemActivity.this);

        agregarItemURL = "YOUR_URL";
        agregarImagenesURL = "ANOTHER_URL";

        cargarWebSeleccionada(agregarItemURL);
    }

    public void cargarWebSeleccionada(String url){
        Log.i("URL", url);
        myWebView.loadUrl(url);
    }

    /** Method in charge of creating the captured image */
    private File createImageFile() throws IOException {
        // Create an image file name
        String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
        String imageFileName = "JPEG_" + timeStamp + "_";
        File storageDir = Environment.getExternalStoragePublicDirectory(
                Environment.DIRECTORY_PICTURES);
        File imageFile = File.createTempFile(
                imageFileName,  /* prefix */
                ".jpg",         /* suffix */
                storageDir      /* directory */
        );
        return imageFile;
    }
        /** Custom WebChromeClient for our WebView */
        public class ChromeClient extends WebChromeClient {
            // For Android 5.0
            public boolean onShowFileChooser(WebView view, ValueCallback<Uri[]> filePath, WebChromeClient.FileChooserParams fileChooserParams) {
                // Double check that we don't have any existing callbacks
                if (mFilePathCallback != null) {
                    mFilePathCallback.onReceiveValue(null);
                }
                mFilePathCallback = filePath;
                Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                if (takePictureIntent.resolveActivity(getPackageManager()) != null) {
                    // Create the File where the photo should go
                    File photoFile = null;
                    try {
                        photoFile = createImageFile();
                        takePictureIntent.putExtra("PhotoPath", mCameraPhotoPath);
                    } catch (IOException ex) {
                        // Error occurred while creating the File
                        Log.e(TAG, "Unable to create Image File", ex);
                    }
                    // Continue only if the File was successfully created
                    if (photoFile != null) {
                        mCameraPhotoPath = "file:" + photoFile.getAbsolutePath();
                        takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT,
                                Uri.fromFile(photoFile));
                    } else {
                        takePictureIntent = null;
                    }
                }
                Intent contentSelectionIntent = new Intent(Intent.ACTION_GET_CONTENT);
                contentSelectionIntent.addCategory(Intent.CATEGORY_OPENABLE);
                contentSelectionIntent.setType("image/*");
                Intent[] intentArray;
                if (takePictureIntent != null) {
                    intentArray = new Intent[]{takePictureIntent};
                } else {
                    intentArray = new Intent[0];
                }
                Intent chooserIntent = new Intent(Intent.ACTION_CHOOSER);
                chooserIntent.putExtra(Intent.EXTRA_INTENT, contentSelectionIntent);
                chooserIntent.putExtra(Intent.EXTRA_TITLE, "Image Chooser");
                chooserIntent.putExtra(Intent.EXTRA_INITIAL_INTENTS, intentArray);
                startActivityForResult(chooserIntent, INPUT_FILE_REQUEST_CODE);
                return true;
            }
            // openFileChooser for Android 3.0+
            public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType) {
                mUploadMessage = uploadMsg;
                // Create AndroidExampleFolder at sdcard
                // Create AndroidExampleFolder at sdcard
                File imageStorageDir = new File(
                        Environment.getExternalStoragePublicDirectory(
                                Environment.DIRECTORY_PICTURES)
                        , "AndroidExampleFolder");
                if (!imageStorageDir.exists()) {
                    // Create AndroidExampleFolder at sdcard
                    imageStorageDir.mkdirs();
                }
                // Create camera captured image file path and name
                File file = new File(
                        imageStorageDir + File.separator + "IMG_"
                                + String.valueOf(System.currentTimeMillis())
                                + ".jpg");
                mCapturedImageURI = Uri.fromFile(file);
                // Camera capture image intent
                final Intent captureIntent = new Intent(
                        android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
                captureIntent.putExtra(MediaStore.EXTRA_OUTPUT, mCapturedImageURI);
                Intent i = new Intent(Intent.ACTION_GET_CONTENT);
                i.addCategory(Intent.CATEGORY_OPENABLE);
                i.setType("image/*");
                // Create file chooser intent
                Intent chooserIntent = Intent.createChooser(i, "Image Chooser");
                // Set camera intent to file chooser
                chooserIntent.putExtra(Intent.EXTRA_INITIAL_INTENTS
                        , new Parcelable[] { captureIntent });
                // On select image call onActivityResult method of activity
                startActivityForResult(chooserIntent, FILECHOOSER_RESULTCODE);
            }
            // openFileChooser for Android < 3.0
            public void openFileChooser(ValueCallback<Uri> uploadMsg) {
                openFileChooser(uploadMsg, "");
            }
            //openFileChooser for other Android versions
            public void openFileChooser(ValueCallback<Uri> uploadMsg,
                                        String acceptType,
                                        String capture) {
                openFileChooser(uploadMsg, acceptType);
            }
        }
    }