mà như tôi đã đề cập trong Chương 7 được sử dụng để hạn chế instantiation của một lớp với một đối tượng. Điều này được thực hiện thông qua một phương pháp học, thường là getInstance (), tạo ra một thể hiện mới của lớp học nếu không tồn tại. Nếu dụ một đã tồn tại, nó chỉ đơn giản trả về | Chapter 13 BUILDING THE JOBS BOARD By Omar Gonzalez In this chapter I am going to cover the building of the jobs board for the RMX starting with setting up the Drupal side and then shifting quickly to building the Flex interface. I will discuss retrieving records from a Drupal data source and displaying those records in a Flex-powered interface and end with reviewing how I built the view filters in the Flex interface. You ve already explored some of these concepts so now it s time to put them to practical use. But first Chris Charlton is going to cover content management and our overall use of Drupal. Content management To handle the tons of content being populated by hundreds of user groups worldwide we need what s known as a content management system CMS . A database is required for scalable content management systems and MySQL is more than up for that task so knowing what database software will house our data the only choice left is deciding on the actual CMS. As Hasan discussed in Chapter 12 we selected Drupal as our CMS. Flex and Drupal share a lot in common they re both open source frameworks and have very modular ways of working with data and objects. If one thing can be guaranteed in this book if you spend enough time with either of these frameworks you ll get hooked. 337 CHAPTER 13 So what power does this CMS provide First all the CRUD is handled for us create read update delete allowing us to concentrate on application logic as opposed to writing create read update and delete code from scratch. Since entering and retrieving data for us will be handled by Drupal we only need to concern ourselves with how we re to get that data from Drupal to Flex and back again. This turns out to be easy using an approach that might be new to you Flash Remoting. If you ve never heard of Flash Remoting don t be intimidated it s just another component we re adding to the mix. Adobe has a protocol for Flash and Flex the Action Messaging Format AMF that allows the transparent