Computer Select (Limited Edition)

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Assembly Source File | 1990-07-11 | 8.1 KB | 328 lines

.MODEL SMALL INCLUDE equates.inc INCLUDE instance.inc INCLUDE messages.inc INCLUDE objects.inc MaxSize EQU BufSize-10 ;Maximum number of characters WindowWidth EQU 29 ;Column width of edit window ScrollCols EQU WindowWidth-4 ;Number of columns to scroll IF1 INCLUDE macros.mac INCLUDE objects.mac ENDIF EXTRN disCharacter:NEAR EXTRN makeActive:NEAR EXTRN sendMsg:NEAR EXTRN Buffer:WORD EXTRN Cursor:WORD EXTRN Dispatch:WORD EXTRN Keyboard:WORD EXTRN Self:WORD EXTRN SBorder:WORD EXTRN Window:WORD .CODE IF Dbug PUBLIC initEditWinVars ENDIF COMMENT % ============================================================================== Sets EditWin's instance variables with values handed down from the master. =============================================================================% initEditWinVars PROC NEAR push Self getInst$ ch,Row1,MasterObj ;Get upper row from master getInst cl,Col1 ;Get left column getInst dh,Row2 ;Get lower row getInst dl,Col2 ;Get right column add ch,RowOffset ;Add in row offset add ch,RowOffset ;Add in row offset mov dh,ch add dh,2 add cl,ColOffset ;Add in column offset add cl,ColOffset ;Add in column offset mov dl,cl add dl,WindowWidth+4 setInst Row1,ch,EditWin ;Set upper row setInst Col1,cl ;Set left column setInst Row2,dh ;Set lower row setInst Col2,dl ;Set right column setInst InxPtr,0,,2 ;Clear char count inc ch setInst Row1,ch,Cursor ;Set cursor row add cl,ColOffset ;Add in column offset setInst Col1,cl ;Set cursor column pop Self ret initEditWinVars ENDP COMMENT % ============================================================================== Displays an ASCII character, or performs a function based on the last key event. =============================================================================% handleEvent PROC NEAR getInst ah,ScanCode,Keyboard ;Get scan code null ah,hdl1 ;Invalid key - Exit getInst al,AsciiCode ;Get char code moreThan al,126,hdl1 ;> 126? - Exit lessThan al,32,hdl2 ;< 32? - Check if command call disChar ;Display if char jmp hdl1 hdl2: call processCmd ;Process if command hdl1: ret handleEvent ENDP COMMENT % ============================================================================== Processes keyboard commands based on ASCII and scan codes for EditWin. Passed: al - Character code =============================================================================% processCmd PROC NEAR lea si,EditWinDispTbl ;Get addr of dispatch tbl pcmd1: eq al,Bptr[si],pcmd2 ;Match ASCII code? - Exit loop add si,3 ;Else - Point to next entry identity Bptr[si],pcmd1 ;More? - Keep looking pcmd2: call Wptr[si+1] ;Call procedure ret processCmd ENDP COMMENT % ============================================================================== Displays an ASCII character in the EditWindow. Passed: al - Character code =============================================================================% disChar PROC NEAR call getInstVars ;Get instance variables neq cx,MaxSize,dchr1 ;Room in buffer? - Skip call invalidKey ;Else - Alert user jmp dchr3 ;Exit dchr1: add di,cx ;Point to end of buffer mov Bptr[di],bh ;Save new char there mov Bptr[di+1],0 ;Save zero in next position inc cx ;Increment char count setInst InxPtr,cx ;Save new count getInst dl,Col1,Cursor ;Get cursor column neq dl,al,dchr2 ;Not at edge? - Skip push si ;Else - Save obj ptr send Self,ScrollLeft,ScrollCols pop si ;Restore obj ptr dchr2: call disCharacter ;Display character inc dl ;Increment column setInst Col1,dl ;Update cursor column dchr3: ret disChar ENDP COMMENT % ============================================================================== Returns important EditWindow instance variables. Passed: al - Character code Passes: ax - Lower/Right row/column bh - Character code bl - Color cx - Character count di - Text input buffer pointer dx - Upper/Left row/column =============================================================================% getInstVars PROC NEAR getInst dh,Row1,Self ;Get upper row inc dh ;Increment row getInst dl,Col1 ;Get left column add dl,ColOffset ;Add in column offset getInst bl,Color ;Get color mov bh,al ;Pass char code in bh getInst ah,Row2 ;Get lower row dec ah getInst al,Col2 ;Get right column sub al,ColOffset ;Subtract column offset getInst cx,InxPtr ;Get character count getInst di,TxtPtr ;Get text input buffer addr ret getInstVars ENDP IF Dbug PUBLIC backSpace ENDIF COMMENT % ============================================================================== Deletes the character to left of cursor scring if necessary. =============================================================================% backSpace PROC NEAR call getInstVars ;Get instance variables notZero cx,bksp1 ;Chars in buffer? - Skip call invalidKey ;Else - Alert user jmp bksp3 ;Exit bksp1: dec cx ;Decrement char count setInst InxPtr,cx ;Save new count add di,cx ;Point to last char in buffer mov Bptr[di],0 ;Replace with a zero mov al,dl ;Get left column getInst dl,Col1,Cursor ;Get cursor column dec dl ;Decrement column setInst Col1,dl ;Update cursor column neq dl,al,bksp2 ;Not at edge? - Skip send Self,ScrollRight,ScrollCols bksp2: mov bh,Space ;Pass blank character call disCharacter ;Display character bksp3: ret backSpace ENDP COMMENT % ============================================================================== Scrolls a line of text to the left. Passed: StackTop - Number of columns to scroll =============================================================================% scrLeft PROC NEAR call getInstVars ;Get instance variables add di,cx ;Point to end of text sub di,WindowWidth ;Point to 1st char in window getStackArgs cx ;Get #columns to scroll add di,cx ;Point to new 1st char mov ax,WindowWidth ;Calculate loop count sub ax,cx mov cx,ax scrl1: mov bh,Bptr[di] ;Get character call disCharacter ;Display it inc dl ;Next column inc di ;Next character loop scrl1 dec dl setInst Col1,dl,Cursor ;Update cursor position ret scrLeft ENDP IF Dbug PUBLIC scrRight ENDIF COMMENT % ============================================================================== Scrolls a line of text to the right. Passed: StackTop - Number of columns to scroll =============================================================================% scrRight PROC NEAR call getInstVars ;Get instance variables zero cx,scrr2 ;No chars in buffer? - Exit add di,cx ;Point to end of text getStackArgs ax ;Get #columns to scroll lessThan cx,ax,scrr3 ;Not enough chars? - Skip mov cx,ax ;Set up loop counter scrr3: sub di,cx ;Point to 1st char in window scrr1: mov bh,Bptr[di] ;Get character call disCharacter ;Display it inc dl ;Next column inc di ;Next character loop scrr1 setInst Col1,dl,Cursor ;Update cursor position scrr2: ret scrRight ENDP COMMENT % ============================================================================== Alerts user as to invalid input. =============================================================================% invalidKey PROC NEAR push Self send Dispatch,Update ;Alert user pop Self ret invalidKey ENDP .DATA EditWinDispTbl LABEL WORD DB 008 DW OFFSET backSpace DB Nil DW OFFSET invalidKey defMsg EditWin,\ Refresh,\ <initEditWinVars,,> defMsg EditWin,\ Read,\ <handleEvent,,makeActive> defMsg EditWin,\ ScrollLeft,\ <,,scrLeft> defMsg EditWin,\ ScrollRight,\ <,,scrRight> defObj EditWin,\ <Window,SBorder>,\ <Row1,1,11,\ Col1,1,17,\ Row2,1,13,\ Col2,1,36,\ Color,1,34h,\ Unused,1,Nil,\ TxtPtr,2,Buffer,\ InxPtr,2,0,\ MasterObj,2,Nil>,\ <Refresh,Read,ScrollLeft,ScrollRight> END