DFHMDF

What DFHMDF does

• DFHMDF defines one screen field - that is, one attribute byte - inside a map.
• The label (1 to 29 characters) names the field; only named fields appear in the symbolic map.
• Fields without a label are constants: captions, titles, instructions and legends.
• A data entry field is normally coded as a pair: the entry field (UNPROT) followed by a 1-byte ASKIP field that marks its end.

Common parameters

• POS=(line,column): the position of the attribute byte on the screen.
• LENGTH: the length of the field, not counting the attribute byte.
• ATTRB: attribute settings - intensity BRT/NORM/DRK, protection PROT/ASKIP/UNPROT, NUM (numeric lock, right-justified zero-filled), IC (place cursor here), FSET (turn MDT on before sending).
• COLOR: BLUE, RED, PINK, GREEN, TURQUOISE, YELLOW, NEUTRAL or DEFAULT.
• HILIGHT: BLINK, REVERSE, UNDERLINE or OFF.
• INITIAL: the starting text of the field; if omitted the default is hexadecimal zeros (low-value).
• PICIN / PICOUT: COBOL pictures for input/output editing, for example PICOUT='ZZ,ZZZ,ZZ9.99'. If omitted, X(n) is assumed.

Typical field patterns

• Data entry field: UNPROT with a color like TURQUOISE, underlined so users can see it, plus a trailing 1-byte ASKIP field.
• Display-only numeric field: PROT with PICOUT so amounts print edited, for example a balance due field.
• Message area: a long PROT field in bright yellow (BRT) on line 23.
• Last field of the map: a 1-byte DUMMY with ATTRB=(DRK,PROT,FSET) and INITIAL=' ' so at least one byte is always sent back.
• Example:-
  
  CUSTNO DFHMDF POS=(5,26), X LENGTH=6, X ATTRB=(NORM,UNPROT,IC), X COLOR=TURQUOISE, X INITIAL='______' DFHMDF POS=(5,33), X LENGTH=1, X ATTRB=ASKIP