在平常的ABAP开发过程中，这一类需求非常常见(一般见于Dialog program)：屏幕上其他element需要在不触发PAI的情况下去读取其他UI element中的用户输入值(如以取得的该值作为本UI Element的限制条件)。如下，记录一下这种需求中最常见的一个简单实例。
1. 需求
屏幕上的第二个field的F4需要以第一个field的输入为条件。
首先使用数据：
屏幕操作如下：
如果第一个field不输入:
如果第二个field已经手动输入则不需要F4:
如果第一个field输入值但检索不到数据:
如果第一个field输入值但检索到数据:
然后可以选择：
2. 实现
先看一下在PAI（value-request）时是否能得到parameter输入的值.
当在第一个field carrid中输入值后，debug：
可以发现，在该event-block中并不能得到parameter的输入值。所以，必须得想法去取得屏幕上的值。
测试程序：
*&———————————————————————*
*& Report ZTEST_F4_DYNPRO
*&
*&———————————————————————*
*& Read Dynpro Parameter for F4
*&
*&———————————————————————* REPORT ZTEST_F4_DYNPRO MESSAGE-ID ztest1. *data
DATA:
ls_dyn_field type dynpread, “Very important
lt_dyn_field type TABLE OF dynpread.
DATA:
ls_spfli type spfli,
lt_spfli like TABLE OF ls_spfli. * parameters
PARAMETERS:
p_carrid type spfli-carrid,
p_connid type spfli-connid. * PBO
AT SELECTION-SCREEN OUTPUT.
ls_dyn_field-fieldname = ‘P_CARRID’.
APPEND ls_dyn_field to lt_dyn_field. “ carrid
ls_dyn_field-fieldname = ‘P_CONNID’.
APPEND ls_dyn_field to lt_dyn_field. “ Connid * PAI(Value-Request)
AT SELECTION-SCREEN on VALUE-REQUEST FOR p_connid.
“1. get the values in the dynpro
CALL FUNCTION ‘DYNP_VALUES_READ’
EXPORTING
DYNAME = sy-repid
DYNUMB = sy-dynnr
* TRANSLATE_TO_UPPER = ’ ’
* REQUEST = ’ ’
* PERFORM_CONVERSION_EXITS = ’ ’
* PERFORM_INPUT_CONVERSION = ’ ’
* DETERMINE_LOOP_INDEX = ’ ’
* START_SEARCH_IN_CURRENT_SCREEN = ’ ’
* START_SEARCH_IN_MAIN_SCREEN = ’ ’
* START_SEARCH_IN_STACKED_SCREEN = ’ ’
* START_SEARCH_ON_SCR_STACKPOS = ’ ’
* SEARCH_OWN_SUBSCREENS_FIRST = ’ ’
* SEARCHPATH_OF_SUBSCREEN_AREAS = ’ ’
TABLES
DYNPFIELDS = lt_dyn_field
EXCEPTIONS
INVALID_ABAPWORKAREA = 1
INVALID_DYNPROFIELD = 2
INVALID_DYNPRONAME = 3
INVALID_DYNPRONUMMER = 4
INVALID_REQUEST = 5
NO_FIELDDESCRIPTION = 6
INVALID_PARAMETER = 7
UNDEFIND_ERROR = 8
DOUBLE_CONVERSION = 9
STEPL_NOT_FOUND = 10
OTHERS = 11 .
IF SY-SUBRC <> 0.
WRITE:/ ‘Error occurs in Read_value.’.
LEAVE LIST-PROCESSING.
ENDIF. “2. check if Connid has already been input
READ TABLE lt_dyn_field into ls_dyn_field with key FIELDNAME = ‘P_CONNID’.
IF ls_dyn_field-FIELDVALUE is NOT INITIAL.
“You have already input data in CONNID’.
MESSAGE i028.
EXIT.
ENDIF. “3. get the CARIID value of user-input
READ TABLE lt_dyn_field into ls_dyn_field with key FIELDNAME = ‘P_CARRID’.
IF ls_dyn_field-FIELDVALUE is INITIAL.
“You should first input data in CARRID’.
MESSAGE i029.
exit.
ENDIF. “4. get the table-value from BD
SELECT * from spfli into TABLE lt_spfli
WHERE carrid = ls_dyn_field-FIELDVALUE.
IF sy-subrc <> 0.
“No data found for your input of CARRID.
MESSAGE i030.
exit.
ENDIF. “5. form the F4Help
CALL FUNCTION ‘F4IF_INT_TABLE_VALUE_REQUEST’
EXPORTING
* DDIC_STRUCTURE = ’ ’
RETFIELD = ‘CONNID’
* PVALKEY = ’ ’
DYNPPROG = sy-repid
DYNPNR = sy-dynnr
DYNPROFIELD = ‘P_CONNID’
* STEPL = 0
* WINDOW_TITLE =
* VALUE = ’ ’
VALUE_ORG = ‘S’ “S:Structure;Default(C):cell by cell
* MULTIPLE_CHOICE = ’ ’
* DISPLAY = ’ ’
* CALLBACK_PROGRAM = ’ ’
* CALLBACK_FORM = ’ ’
* MARK_TAB =
* IMPORTING
* USER_RESET =
TABLES
VALUE_TAB = lt_spfli
* FIELD_TAB =
* RETURN_TAB =
* DYNPFLD_MAPPING =
EXCEPTIONS
PARAMETER_ERROR = 1
NO_VALUES_FOUND = 2
OTHERS = 3.
IF SY-SUBRC <> 0.
“Error occurs in F4 for CONNID.
MESSAGE i031.
EXIT.
ENDIF. |
关于该程序中使用到的这两个FM(一个用于读取screen上的value；一个用于限制F4)，均可以在SE37中进行check。
