A version of Liferay JS services that return synchronously (not recommended)

get_service_sync.js

function getServiceSync() {
	var xhr = null;
	var args = parent.Liferay.Service.parseInvokeArgs(arguments);

	var syncIOConfig = {
		sync: true,
		on: {
			success: function(event, id, obj){
				xhr = obj;
			}
		}
	};

	args[1] = parent.AUI().merge(args[1], syncIOConfig);

	parent.Liferay.Service.invoke.apply(Liferay.Service, args);

	if(xhr){
		return eval('(' + xhr.responseText + ')');
	}
};

getServiceSync(
	'/mbcategory/get-categories',
	{
		groupId: themeDisplay.getScopeGroupId(),
		parentCategoryId: 0,
		status: 0,
		start: -1,
		end: -1
	}
);