public static void checkForUpdatesAndDownloadAll(final MainActivity activity, final int layout, final Download.DownloadType type, @StringRes final int title, @StringRes final int info, final Action1<Boolean> callback) {
        activity.displayActionItem(layout, info, true, (actionRequested) -> {
            if (actionRequested) {
                new CheckForDownloadsTask(activity, title, type).execute();
            }
            callback.call(actionRequested);
        });
    }
displays an info to the user to check for updates
if button pressed: checks whether updates are available for the type specified
if yes: ask user to download them all
if yes: trigger download(s)
main/src/main/java/cgeo/geocaching/downloader/DownloaderUtils.java