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Text File | 1988-01-19 | 13.0 KB | 277 lines

MAKEBAR Robert L. Hummel Command 1987/No. 10 (Lab Notes) ______________________________________________________ Purpose: Compiles Lotus-style menus for non-Lotus applications programs for use with the SLASHBAR.COM utility contained on this disk. Format: MAKEBAR [path]input_file [path]output_file Remarks: The input_file must contain the keystrokes needed to activate the application program's commands, and it must be constructed using the .BDF format and syntax illustrated by the ASCII-readable DOS.BDF file contained on this disk. The output_file produced by MAKEBAR is a .BAR file suitable for loading as a pop-up window by SLASHBAR. Maximum length of the compiled .BAR file is approximately 46,000 bytes. Constructing a suitable .BDF file for an application is not a trivial undertaking, and a thorough study of the original article is recommended, if at all possible. The first step is to organize the commands needed by the application into a menu-tree arrangement similar to the DOS menu tree shown below on the following page. The categories in the left column will appear on the first line of the first menu screen. CLS is immediately run from that screen, so it has no lower branches. |- COPY |- FILE --|- DIR | |- ERASE | |- RENAME | |- TYPE | | |- ASSIGN | | |- PARENT | |- CHDIR ----|- ROOT | | |- OTHER | |- FORMAT |- DISK --|- LABEL | |- MKDIR | |- RMDIR | |- VOL | | |- DATE |- SYSTEM -|- TIME | |- PROMPT | |- VER | |- CLS The diagram below shows the basic structure of the MENU...MEND blocks from which a .BDF file is constructed. Again, study the DOS.BDF file on this disk. PROGRAM "NAME" ---------- Identification Name MENU NAME -----------------------------------| OPTION NAME,"HELP LINE" --| | COMMANDS -| | | . |-- Commands |-- Option | . | | Block | . -| --| |-- Menu OPTION NAME,"HELP LINE" | Block COMMANDS | . | . | . | MEND ----------------------------------------| MENU NAME----| . | Additional menu . |--block(s) as . | required MEND---------| END -------- End Of File Indicator Precede any comments you may wish to include in a .BDF menu file with a semicolon. MAKEBAR ignores the remainder of any line when it encounters the semicolon character. Use the {c}1 key combination to represent the semicolon in any names or quoted strings your application requires. Two types of text entries are used in menu files. A STRING is an entry surrounded by quotes ("). "DOS 3.1" and "JiffyCalc Spreadsheet" are examples of valid strings. A string may not contain the quote character, but you can use the {c}3 sequence to represent it in a string. A NAME is an entry consisting of a single word, and must contain no spaces. To aid readability, separation characters may be used in names: DO-THIS, DO_THAT, DO$IT$NOW, are all valid. Upper/Lower case is preserved in strings, but names are capitalized in the output file. Strings may contain any character or key combination (except the comment and quote characters) that can be recognized by the BIOS. Key combinations in a BDF that are not recognized by the BIOS will produce an error message. (There may therefore be some commands for a given application that cannot be included in the menu structure.) Alpha-numeric keys are entered by typing them. All special keys, such as the function keys and shift-key combinations are entered in symbolic form as text surrounded by braces. The Shift, Ctrl, and Alt keys affect only the immediately following key. The available special keys and their representation in a .BDF file are: {ESC} Escape {U} Arrow Up {TAB} Tab {D} Arrow Down {ENTER} ENTER {L} Arrow Left {BS} Backspace {R} Arrow Right {HOME} Home {INS} Insert {PGUP} Page Up {DEL} Delete {PGDN} Page Down {C} Control {END} End {S} Shift {A} Alt Function Keys {F1} {F2} {F3} {F4} {F5} {F6} {F7} {F8} {F9} {F10} Redundant key combinations, such as {S}a instead of A, will produce an error message. Example: To block out a paragraph in WordPerfect the sequence would be: "{A}{F4}{ENTER}" To enter the WordStar Ctrl-KD sequence (to end editing and save changes), you would use the string: "{C}KD" To replace the current file in 1-2-3, enter: "/FSR" A .BDF file always begins with the word PROGRAM, followed by a string. The first 10 characters of the string are encoded in the compiled .BAR file for display in the pop-up window. PROGRAM must be the first non-comment line in the program, and it must appear only once. Conversely, END causes processing of the input file to cease and is the last command read. Each .BDF file must include an END. The remainder of the file consists of MENU-MEND blocks, as was diagrammed above. Each block corresponds to one complete set of command choices. In the DOS.BDF example there are five menu blocks: the top-level block; three second level blocks (to represent the FILE, DISK, and SYSTEM submenus); and one third level block (the CHDIR sub-submenu). Note that the CLS option does not require a menu block since that command terminates at the first level. The MENU block that follows the PROGRAM command is assumed to be the top level menu and will be the first one to be executed. Subsequent MENU blocks may be in any order. Each MENU statement takes a NAME as its argument, and no two menus can have the same name. The name is used as a target when control is transferred between menus with the EXECUTE command. Using identical menu names will cause MAKEBAR to report a Bad Menu Reference. The MENU block is divided into one or more OPTION blocks. An OPTION block comprises three separate parts: name, help line, and commands. While, like a menu, each option must have a name, there are no restrictions as to uniqueness. The same option name may be used in different menus with different meanings, though this would not be the best design for a consistent interface. Because options may be selected by pressing their first letter, if two options begin with the same letter, the second option can never be executed by pressing that letter. (It can be invoked by positioning the cursor and pressing ENTER.) This property could be used to prevent accidental use of a command by making it more difficult to invoke. The help string must follow each option name on the same line. This string will be displayed below the option names when that option is selected with the cursor. The length of this string must be less than 78 characters in order to fit within the window created by SLASHBAR. Beginning on the next line, the application program commands to be executed when that option is chosen are entered. Each command must begin on a separate line, and the entire command must be contained on that line. If more keys need to be entered than can fit on a single line, multiple TYPE statements (see below) can be used. The BDF commands, with their syntax, are listed below: PROGRAM "string" END MENU name MEND OPTION name, "string" ASK "string" INPUT TYPE "string" CR Remember that a name is a single word with no separating spaces, and that a "string" is a series of characters surrounded by quotes ("). The quotes symbol itself cannot be used within a string, but it can be represented in a string by the {c}3 sequence. A number of these commands have been discussed above. The five that remain, EXECUTE, ASK, TYPE, INPUT, and CR, may only appear inside an OPTION block. These commands make up a kind of batch language that controls the operation of the SLASHBAR utility. At the end of each menu path is a command string that will accomplish the desired result when fed to the applications program, just as if you typed in the commands directly. The EXECUTE command transfers control down the menu tree. Any option may invoke another menu by executing it. Since menu flow is one-way, lines appearing below an EXECUTE command within the same OPTION block will never be invoked. In addition, since paths in the menu tree may not cross, two option blocks cannot execute the same menu. MAKEBAR checks for this and signals it as an error. This prevents building a circular reference into the tree, where a menu could call itself indefinitely. The ASK command is used to prompt the user for information. The string argument appears on the screen in the upper half of the pop-up window and does not affect the output keystrokes. Because the logical use of the ASK command is to request a reply, it is usually followed by the INPUT command. By using these commands together, it is possible to solicit information to complete a command sequence. The INPUT command accepts input from the keyboard and appends it to the current command string. The input is buffered, and the backspace key can be used to correct the entry. Up to 78 characters may be entered, and input terminates when the Enter key is pressed. The keys are put in the command string as they were typed without the terminating <Enter>. The TYPE command copies the keys in the string argument to the command string. Special keys (i.e., function keys and shift-key combinations) are stored with a special code to indicate that they are extended ASCII. A special case of the TYPE command is the CR command. It is equivalent to the command TYPE "{ENTER}" and is included simply for convenience in closing commands after requesting an input.