onShowFileChooser() from android webview works only once

firstly, sorry to my english. you should return empty Uri[]{} to file receive

mUploadMessageForAndroid5.onReceiveValue(new Uri[]{});

my code can choose take photo or local image:

private static final int REQUEST_GET_THE_THUMBNAIL = 4000;
private static final long ANIMATION_DURATION = 200;
public final static int FILECHOOSER_RESULTCODE = 1;
public final static int FILECHOOSER_RESULTCODE_FOR_ANDROID_5 = 2;

//JS
webView.getSettings().setJavaScriptEnabled(true);

//set ChromeClient
webView.setWebChromeClient(getChromeClient());

//ChromeClinet配置
private WebChromeClient getChromeClient() {
    return new WebChromeClient() {

        //3.0++
        public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType) {
            openFileChooserImpl(uploadMsg);
        }

        //3.0--
        public void openFileChooser(ValueCallback<Uri> uploadMsg) {
            openFileChooserImpl(uploadMsg);
        }

        public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType, String capture) {
            openFileChooserImpl(uploadMsg);
        }

        // For Android > 5.0
        public boolean onShowFileChooser(WebView webView, ValueCallback<Uri[]> uploadMsg, WebChromeClient.FileChooserParams fileChooserParams) {
            openFileChooserImplForAndroid5(uploadMsg);
            return true;
        }

    };
}

private void openFileChooserImpl(ValueCallback<Uri> uploadMsg) {
    mUploadMessage = uploadMsg;
    new AlertDialog.Builder(mActivity)
            .setItems(items, new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    if (items[which].equals(items[0])) {
                        Intent i = new Intent(Intent.ACTION_GET_CONTENT);
                        i.addCategory(Intent.CATEGORY_OPENABLE);
                        i.setType("image/*");
                        startActivityForResult(Intent.createChooser(i, "File Chooser"), FILECHOOSER_RESULTCODE);
                    } else if (items[which].equals(items[1])) {
                        dispatchTakePictureIntent();
                    }
                    dialog.dismiss();
                }
            })
            .setOnCancelListener(new DialogInterface.OnCancelListener() {
                @Override
                public void onCancel(DialogInterface dialog) {
                    Log.v(TAG, TAG + " # onCancel");
                    mUploadMessage = null;
                    dialog.dismiss();
            }})
            .show();
}

private void openFileChooserImplForAndroid5(ValueCallback<Uri[]> uploadMsg) {
    mUploadMessageForAndroid5 = uploadMsg;

    new AlertDialog.Builder(mActivity)
            .setItems(items, new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    if (items[which].equals(items[0])) {
                        Intent contentSelectionIntent = new Intent(Intent.ACTION_GET_CONTENT);
                        contentSelectionIntent.addCategory(Intent.CATEGORY_OPENABLE);
                        contentSelectionIntent.setType("image/*");

                        Intent chooserIntent = new Intent(Intent.ACTION_CHOOSER);
                        chooserIntent.putExtra(Intent.EXTRA_INTENT, contentSelectionIntent);
                        chooserIntent.putExtra(Intent.EXTRA_TITLE, "Image Chooser");

                        startActivityForResult(chooserIntent, FILECHOOSER_RESULTCODE_FOR_ANDROID_5);
                    } else if (items[which].equals(items[1])) {
                        dispatchTakePictureIntent();
                    }
                    dialog.dismiss();
                }
            })
            .setOnCancelListener(new DialogInterface.OnCancelListener() {
                @Override
                public void onCancel(DialogInterface dialog) {
                    Log.v(TAG, TAG + " # onCancel");
                    //important to return new Uri[]{}, when nothing to do. This can slove input file wrok for once.
                    //InputEventReceiver: Attempted to finish an input event but the input event receiver has already been disposed.
                    mUploadMessageForAndroid5.onReceiveValue(new Uri[]{});
                    mUploadMessageForAndroid5 = null;
                    dialog.dismiss();
            }}).show();
}

private void dispatchTakePictureIntent() {
    Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
    if (takePictureIntent.resolveActivity(mActivity.getPackageManager()) != null) {
//            File file = new File(createImageFile());
        Uri imageUri = null;
        try {
            imageUri = Uri.fromFile(createImageFile());
        } catch (IOException e) {
            e.printStackTrace();
        }
        //temp sd card file
        takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
        startActivityForResult(takePictureIntent, REQUEST_GET_THE_THUMBNAIL);
    }
}

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 = new File(Environment.getExternalStorageDirectory().getAbsolutePath() + "/don_test/");
    if (!storageDir.exists()) {
        storageDir.mkdirs();
    }
    File image = File.createTempFile(
            imageFileName,  /* prefix */
            ".jpg",         /* suffix */
            storageDir      /* directory */
    );

    // Save a file: path for use with ACTION_VIEW intents
    mCurrentPhotoPath = image.getAbsolutePath();
    return image;
}

@Override
public void onActivityResult(int requestCode, int resultCode, Intent intent) {
    Log.v(TAG, TAG + " # onActivityResult # requestCode=" + requestCode + " # resultCode=" + resultCode);
    if (requestCode == FILECHOOSER_RESULTCODE) {
        if (null == mUploadMessage)
            return;
        Uri result = intent == null || resultCode != Activity.RESULT_OK ? null : intent.getData();
        mUploadMessage.onReceiveValue(result);
        mUploadMessage = null;

    } else if (requestCode == FILECHOOSER_RESULTCODE_FOR_ANDROID_5) {
        if (null == mUploadMessageForAndroid5)
            return;
        Uri result;

        if (intent == null || resultCode != Activity.RESULT_OK) {
            result = null;
        } else {
            result = intent.getData();
        }

        if (result != null) {
            Log.v(TAG, TAG + " # result.getPath()=" + result.getPath());
            mUploadMessageForAndroid5.onReceiveValue(new Uri[]{result});
        } else {
            mUploadMessageForAndroid5.onReceiveValue(new Uri[]{});
        }
        mUploadMessageForAndroid5 = null;
    } else if (requestCode == REQUEST_GET_THE_THUMBNAIL) {
        if (resultCode == Activity.RESULT_OK) {
            File file = new File(mCurrentPhotoPath);
            Uri localUri = Uri.fromFile(file);
            Intent localIntent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE, localUri);
            mActivity.sendBroadcast(localIntent);

            Uri result = Uri.fromFile(file);
            mUploadMessageForAndroid5.onReceiveValue(new Uri[]{result});
            mUploadMessageForAndroid5 = null;
        } else {

            File file = new File(mCurrentPhotoPath);
            Log.v(TAG, TAG + " # file=" + file.exists());
            if (file.exists()) {
                file.delete();
            }
        }
    }
}