Data aware forms for non-standard databases

Though the Forms Designer table list is only available for the native KCML database, data aware forms can be used with any database by defining suitable field variables.

• Define a row buffer which you can populate from your database and use the name of that variable as the DataSource property on the bound controls.
• Define field variables specifying datatype and offset within the buffer for each of the bound controls.
• Set the DataField property of each bound control to the name of the field that contains the column. Don't supply the leading dot. This can be done either programmatically or you can use the Forms Designer.
• Write a function which will populate the row buffer. This can be called in the Enter() event or before the form is opened to establish initial values. You may have navigation buttons on the form which can load other buffers as necessary.

Here is an example program showing binding from a static buffer.

DIM row$100, N=5, count, ethis, x
DIM n$(N)30, salary(N), eenum(N)
DIM .name$=(1, 30), .salary=(31, "B4"), .eenum=(35, "B2")
count = 0
WHILE count <= N DO
READ x
IF (x == 0) THEN BREAK
eenum(++count) = x
READ n$(count), salary(count)
WEND
- DEFFORM SalForm()={.form,.form$,.Style=0x50c000c4,.Width=259,.Height=156,.text$="Employee database",.Id=1024},{.ok,.button$,.Style=0x50010001,.Left=203,.Top=6,.Width=50,.Height=14,.text$="OK",.__Anchor=5,.Id=1},\
{.cancel,.button$,.Style=0x50010000,.Left=203,.Top=23,.Width=50,.Height=14,.text$="Cancel",.__Anchor=5,.Id=2},\
{.editgroup1,.EditGroup$,.Left=10,.Top=20,.Width=187,.Height=127,.Id=1000},\
{.editControl1,.kcmldbedit$,.Style=0x50810080,.Left=107,.Top=36,.Width=45,.Height=15,.Id=1001,.ReadOnly=1,.DataSource=row$,.DataField=.eenum,.EditGroup=.editgroup1,.label$="Employee:"},\
{.editControl2,.kcmldbedit$,.Style=0x50810080,.Left=67,.Top=66,.Width=122,.Height=15,.Id=1002,.ReadOnly=1,.DataSource=row$,.DataField=.name$,.DBEnabled=1,.EditGroup=.editgroup1,.label$="name:"},\
{.editControl3,.kcmldbedit$,.Style=0x50810080,.Left=102,.Top=96,.Width=53,.Height=15,.Id=1003,.ReadOnly=1,.DataSource=row$,.DataField=.salary,.DBEnabled=1,.EditGroup=.editgroup1,.label$="Salary:"},\
{.cmdPrev,.button$,.Style=0x50010000,.Left=209,.Top=87,.Width=43,.Height=15,.text$="prev",.Id=1004,.Click()},\
{.cmdNext,.button$,.Style=0x50010000,.Left=209,.Top=107,.Width=43,.Height=15,.text$="next",.Id=1005,.Click()},\
{.cmdFirst,.button$,.Style=0x50010000,.Left=209,.Top=68,.Width=43,.Height=15,.text$="first",.Id=1006,.Click()},\
{.cmdLast,.button$,.Style=0x50010000,.Left=209,.Top=127,.Width=43,.Height=15,.text$="last",.Id=1007,.Click()}
+ DEFEVENT SalForm.Enter()
'GetEmployee(1)
END EVENT
+ DEFEVENT SalForm.cmdPrev.Click()
'GetEmployee(--ethis)
END EVENT
+ DEFEVENT SalForm.cmdNext.Click()
'GetEmployee(++ethis)
END EVENT
+ DEFEVENT SalForm.cmdFirst.Click()
'GetEmployee(1)
END EVENT
+ DEFEVENT SalForm.cmdLast.Click()
'GetEmployee(count)
END EVENT
FORM END SalForm
SalForm.Open()
END
DEFSUB 'GetEmployee(e)
REM populate row buffer from the database
IF (e > 0 AND e <= count)
FLD(row$.eenum) = eenum(e)
FLD(row$.name$) = n$(e)
FLD(row$.salary) = salary(e)
ethis = e
END IF
END SUB
REM some employees
DATA 1, "Alan", 10000
DATA 2, "Betty", 20000
DATA 3, "Charlie", 30000
DATA 4, "Dorothy", 20000
DATA 8, "Edward", 14000
DATA 0