@Override
    protected Boolean doInBackgroundInternal(final Geocache[] caches) {
        // export all field notes, without any filtering by connector
        final FieldNotes fieldNotes = createFieldNotes(caches);
        if (fieldNotes == null) {
            return false;
        }

        // write to uri
        exportUri = fieldNotes.writeToFolder(PersistableFolder.FIELD_NOTES.getFolder(), filename);
        if (exportUri == null) {
            return false;
        }
        fieldNotesCount = fieldNotes.size();
        // upload same file to multiple connectors, if they support the upload
        return uploadFieldNotes();
    }
Instantiates and configures the task for exporting field notes.

@param activity optional: Show a progress bar and toasts
@param upload   Upload the Field Note to geocaching.com
@param onlyNew  Upload/export only new logs since last export
main/src/main/java/cgeo/geocaching/export/FieldNoteExportTask.java