cl_gui_cfw=>flush详解编程语言

例如下面让用户选择文件夹的代码：

      CALL METHOD cl_gui_frontend_services=>directory_browse
        CHANGING selected_folder = folder.
      CALL METHOD cl_gui_cfw=>flush.

why should we call the flush method?

here is some notes about this mehtod, from IT虾米网

“In OO approach, calling a Control-method does not imply that the method is automatically executed at runtime. Initially, the system buffers methods in a queue, referred to as the Automation Queue, when they are called in the ABAP program. The execution sequence of the methods therefore remains unchanged. However, the methods are only executed if they are transferred to the frontend via Remote Function Call (RFC) using method FLUSH. This means that the Automation Queue is used to reduce the number of RFC calls required.”

用法三：

在OO的ALV方法中，使程序重新走PBO