At line Selection & get cursor field

Question

Hi friends,
Could any one of u please explain about<b> at line selection</b> and <b>GET CURSOR FIELD</b> ( GET CURSOR FIELD FNAM VALUE FVAL) with sample program.
Jai.

Answer 1

Hello,
AT - Events in lists
Variants:
1. AT LINE-SELECTION.
2. AT USER-COMMAND.
3. AT PFn.
Variant 1
AT LINE-SELECTION.
Effect
Event in interactive reporting
This event is processed whenever the user chooses a valid line in the list (i.e. a line generated by statements such as WRITE,ULINE, or SKIP) with the cursor and presses the function key which has the function PICK in the interface definition. This should normally be the function key F2, because it has the same effect as double-clicking the mouse, or clicking once in the case of a hotspot.
The processing for the event AT LINE-SELECTION usually generates further list output (the details list) which completely covers the current list display. If you want the current list display to remain visible (to aid user orientation), you can do this with the key word WINDOW.
In most cases, the information from the selected line is used to retrieve more comprehensive information by direct reading. When displaying the original list, you store the key terms needed for this in the HIDE area of the output line.
Note
You can choose a line and start new processing even in the details lists.
The following system fields are useful for orientation purposes, since their values change with each interactive event executed.
SY-LSIND
Index of list created by current event (basic list = 0, 1st details list = 1, ...)
SY-PFKEY
Status of displayed list (SET PF-STATUS)
SY-LISEL
Contents of selected line
SY-LILLI
Absolute number of this line in the displayed list
SY-LISTI
Index of this list - usually SY-LSIND - 1 (READ LINE)
SY-CUROW
Last cursor position: Line in window
SY-CUCOL
Last cursor position: Column in window (GET CURSOR)
SY-CPAGE
1st displayed page of displayed list
SY-STARO
1st displayed line of this page of displayed list
SY-STACO
1st displayed column of displayed list (SCROLL LIST)
The system field SY-LSIND defines the line selection level (basic list: SY-LSIND = 0).
System field for interactive reporting are also contained in the System Fields for Lists documentation.
Example
DATA TEXT(20).
START-OF-SELECTION.
  PERFORM WRITE_AND_HIDE USING SPACE SPACE.
AT LINE-SELECTION.
  CASE TEXT.
    WHEN 'List index'.
      PERFORM WRITE_AND_HIDE USING 'X' SPACE.
    WHEN 'User command'.
      PERFORM WRITE_AND_HIDE USING SPACE 'X'.
    WHEN OTHERS.
      SUBTRACT 2 FROM SY-LSIND.
      PERFORM WRITE_AND_HIDE USING SPACE SPACE.
  ENDCASE.
  CLEAR TEXT.
FORM WRITE_AND_HIDE USING P_FLAG_LSIND P_FLAG_UCOMM.
  WRITE / 'SY-LSIND:'.
  PERFORM WRITE_WITH_COLOR USING SY-LSIND P_FLAG_LSIND.
  TEXT = 'List index'.
  HIDE TEXT.
  WRITE / 'SY-UCOMM:'.
  PERFORM WRITE_WITH_COLOR USING SY-UCOMM P_FLAG_UCOMM.
  TEXT = 'User command'.
  HIDE TEXT.
  IF SY-LSIND > 0.
    WRITE / 'PICK here to go back one list level'.
  ENDIF.
ENDFORM.
FORM WRITE_WITH_COLOR USING P_VALUE
                            P_FLAG_POSITIVE.
  IF P_FLAG_POSITIVE = SPACE.
    WRITE P_VALUE COLOR COL_NORMAL.
  ELSE.
    WRITE P_VALUE COLOR COL_POSITIVE.
  ENDIF.
ENDFORM.
Depending on whether you choose the line at SY-LSIND or SY-UCOMM, the next details list contains the corresponding value with the color "positive". If the line is chosen without HIDE information, the list level is reduced.
Variant 2
AT USER-COMMAND.
Effect
Event in interactive reporting
This event is executed whenever the user presses a function key in the list or makes an entry in the command field.
Some functions are executed directly by the system and thus cannot be processed by programs. These include:
PICK
See variant AT LINE-SELECTION
PFn
See variant AT PFn
System command
System command
PRI
Print
BACK
Back
RW
Cancel
P...
Scroll function (e.g.: P+ , P- , PP+3, PS-- etc.)
Instead of this functions, you can use the SCROLL statement in programs.
Since many of these system functions begin with "P", you should avoid using this letter to start your own function codes.
Otherwise, the effect is as for AT LINE-SELECTION; also, the current function code is stored in the system field SY-UCOMM.
Example
DATA: NUMBER1 TYPE I VALUE 20,
      NUMBER2 TYPE I VALUE  5,
      RESULT  TYPE I.
START-OF-SELECTION.
  WRITE: / NUMBER1, '?', NUMBER2.
AT USER-COMMAND.
  CASE SY-UCOMM.
    WHEN 'ADD'.
      RESULT = NUMBER1 + NUMBER2.
    WHEN 'SUBT'.
      RESULT = NUMBER1 - NUMBER2.
    WHEN 'MULT'.
      RESULT = NUMBER1 * NUMBER2.
    WHEN 'DIVI'.
      RESULT = NUMBER1 / NUMBER2.
    WHEN OTHERS.
      WRITE 'Unknown function code'.
      EXIT.
  ENDCASE.
  WRITE: / 'Result:', RESULT.
After entry of a function code, the appropriate processing is performed under the event AT USER-COMMAND and the result is displayed in the details list.
Variant 3
AT PFn.
Effect
Event in interactive reporting
Here, n stands for a numeric value between 0 and 99.
This event is executed whenever the user presses a function key that contains the function code PFn in the interface definition. The default status for lists contains some of these functions.
Otherwise, the effect is as for the variant AT LINE-SELECTION. The cursor can be on any line.
Notes
To ensure that the chosen function is executed only for valid lines, you can check the current HIDE information.
This variant should be used only for test or prototyping purposes, since the default status is not normally used. Instead, you should set a program-specific status with SET PF-STATUS. This should not contain any function codes beginning with "PF".
Example
DATA NUMBER LIKE SY-INDEX.
START-OF-SELECTION.
  DO 9 TIMES.
    WRITE: / 'Row', (2) SY-INDEX.
    NUMBER = SY-INDEX.
    HIDE NUMBER.
  ENDDO.
AT PF8.
  CHECK NOT NUMBER IS INITIAL.
  WRITE: / 'Cursor was in row', (2) NUMBER.
  CLEAR NUMBER.
Additional help
User Action on Detail Lists
GET
Basic form 2 GET CURSOR. ...
Variants:
1. GET CURSOR FIELD f.
2. GET CURSOR LINE line.
Variant 1
GET CURSOR FIELD f.
Additions:
1. ... OFFSET off
2. ... LINE line
3. ... VALUE g
4. ... LENGTH len
5. ... AREA
Effect
Transfers the name of the field at the cursor position to the field f.
The return code is set as follows:
SY-SUBRC = 0:
Cursor was positioned on a field.
SY-SUBRC = 4:
Cursor was not positioned on a field.
Note
Unlike screen processing, list processing allows you to output literals, field symbols, parameters and local variables of subroutines. Literals, local variables and VALUE parameters of subroutines are treated like fields without names (field name SPACE, return value 0).
Otherwise, GET CURSOR FIELD returns only names of global fields, regardless of whether they are addressed directly (i.e. by "WRITE"), by field symbols or by reference parameters.
Example
DATA: CURSORFIELD(20),
      GLOB_FIELD(20)    VALUE 'global field',
      REF_PARAMETER(30) VALUE 'parameter by reference',
      VAL_PARAMETER(30) VALUE 'parameter by value',
      FIELD_SYMBOL(20)  VALUE 'field symbol'.
FIELD-SYMBOLS: <F> TYPE ANY.
PERFORM WRITE_LIST USING REF_PARAMETER VAL_PARAMETER.
ASSIGN GLOB_FIELD TO <F>.
AT LINE-SELECTION.
  GET CURSOR FIELD CURSORFIELD.
  WRITE: /   CURSORFIELD, SY-SUBRC.
FORM WRITE_LIST USING RP VALUE(VP).
  DATA: LOK_FIELD(20)  VALUE 'local field'.
  ASSIGN FIELD_SYMBOL TO <F>.
  WRITE: /  GLOB_FIELD,  /  LOC_FIELD,
         /  RP,          /  VP,
         /  'literal',   /  FIELD_SYMBOL.
ENDFORM.
When you double-click the word " global field", CURSORFIELD contains the field name GLOB_FIELD, on "parameter by reference" the field name REF_PARAMETER, on " field symbol" the field name FIELD_SYMBOL, and on "local field", "parameter by value" and "literal" the value SPACE.
Addition 1
... OFFSET off
Effect
Copies the position of the cursor within the field to the field off (1st column = 0).
If the cursor is not somewhere within a field (SY-SUBRC = 4), the offset value is set to 0.
Addition 2
... LINE line
Effect
With step loops, lin contains the number of the loop line where the cursor stands. In list processing, this is the absolute line number (as stored in the system field SY-LILLI).
Addition 3
... VALUE g
Effect
g contains the value of the field where the cursor stands, always in output format (character display).
Addition 4
... LENGTH len
Effect
len contains the output length of the field where the cursor stands.
Addition 5
... AREA a
Effect
If the cursor is positioned on the field of a table view control, the name of the control is placed in the field a.
Variant 2
GET CURSOR LINE line.
Additions:
1. ... OFFSET off
2. ... VALUE  g
3. ... LENGTH len
Effect
As for variant 1 with addition LINE, except that there are differences with the return code and the effect of the additions.
The return code is set as follows:
SY-SUBRC = 0:
The cursor is on one of the list lines (list processing) or on a loop line (step loop).
SY-SUBRC = 4:
The cursor is not on one of the list or loop lines.
Addition 1
... OFFSET off
Effect
Applies to list processing only. The field off contains the position of the cursor relative to the beginning of the list line (1st column = 0). With horizontally shifted lists, the offset value can thus be greater than 0, even if the cursor is positioned on the extreme left of the window.
Addition 2
... VALUE g
Effect
List processing only. The field g contains the list line where the cursor is positioned.
Addition 3
... LENGTH len
Effect
List processing only. len contains the length of the line (LINE-SIZE).
Related
SET CURSOR
Additional help
Setting the Cursor Position
Reading Lists at the Cursor Position
Vasanth