Push Button not working

hi,

the pushbutton i created doesnt works.help me in this issue.the codings are,

SELECTION-SCREEN PUSHBUTTON /1(10) EXECUTE USER-COMMAND EXEC.

INITIALIZATION.

EXECUTE = 'PUSH'.

IF SSCRFIELD-UCOMM = 'EXEC'.

• even tried with sy-ucomm = 'exec' not working.

PERFORM PRINT.

ENDIF.

FORM PRINT.

WRITE:/ 'TEST PRINT'.

ENDFORM.