The main purpose of a list is to output data in a manner that can be easily understood by the user ; this output often takes on the form of a table.
Lists in R/3 take into account special business data requirement:
1. They are language-independent.Text and headers appear in the logical language whenever the appropriate translation is available.
2. They can output monetary values in numerous currencies.
3. You can output list data in the following ways:
to the screen: here you can add colors and icons.
to the printer
to the internet/intranet:Automatic conversion to HTML
we can also save list in the R/3 System or output them for processing by external commercial software applications like spreadsheet prog.
Each list have a list header and up to four lines of column headers.There are two different ways to go about these tools:
1.from within the Editor using the text-element maintenance functions
2. From within the list itself.If you save your program ,activate it and then run it to create the list, you can enter both list and column headers by choosing the menu path
System -> List -> List headers.
The main advantage of this method is that the list is still displayed on the screen.This makes it easier to position column headers.
The next time we start the program , the new header will appear in the list automatically.
When no header text is entered, the program title is inserted in the header.
Titles and Headersare part of a program’s text elements.We can translate all text elements into other languages.The logon language setting on the logon screen determines which language text elements will be displayed.
Text Symbols are another kind of text elements. These are special text literal data objects.Compared to normal text literals ,text symbols have the advantage that they can be translated into different languages without having to change a program’s source code.Text symbols allow you to create lists independent of language.
In executable programs (type 1) , lists are automatically displayed after their corresponding event blocks have been processed.These processing must , however, contains a list creation statement.These are WRITE,SKIP and ULINE.
Events blocks are called in a sequence designed for list processing:
Prior to sending the selection screen: INITIALIZATION.
After leaving the selection screen : START-OF-SELECTION.
All output from START-OF-SELECTION event blocks, subroutines and function modules that is processed before a list is displayed is temporarily stored in a list buffer.
Once all list creation processing blocks (for example START-OF-SELECTION) have been processed, all data from the list buffer is output in the form of a list.
In executable programs,you can use the event block AT LINE-SELECTION to create detail lists.
The ABAP runtime system:
1. Displays the basic list after the appropriate event blocks have been processed (for example, after START-OF-SELECTION).In this case, system field sy-lsind contains the value zero.
2. Processes the event block ,AT LINE-SELECTION each time we double click on an entry.If we are using a standard status ,this happens automatically every time we choose the Choose icon,the Choose menu item in the EDIT menu, or the function key F2.
3.Displays detailed list after the AT LINE-SELECTION event block has been processed and increases the value contained in sy-lsind by one.
4.Display the detail list from the previous level in the list hierarchy(n-1) every time we choose the green arrow icon from the current detail list(n)
For more details visit,
http://www.saptechies.com/abap-reporting/
