More correctly, a Layout is specific to one form and a specific customization template that you have applied to a form. For instance, you might have Invoice and Packing Slip templates (or others) defined for an Invoice form. FormCalc supports up to ten Layouts, numbered 0...9, so you can have calculations set up for up to ten different forms.
In the illustration above, Layout 0 tab is showing. It has been named "Shipping Weight on Invoice" to serve as a reminder of the Layout's purpose.
An Action describes the details of one particular calculation to be performed...
...such as which column is to be totaled or counted, or which two columns are to be multiplied together to compute values in a third column. Actions then, are the building blocks that make up a Layout.
Layout 0 in the illustration above has two Actions:
❖The Extended Wt. Action calculates the value of column 5 on each row of the detail area, by multiplying the value from column 3 by the value from column 4.
❖The Total Wt. Action totals column 5 and displays the results on the invoice line where the TOTAL WT. Item has been entered. (Items which cause FormCalc to do calculations on specific lines are called trigger Items.)
A Trigger Item is a QuickBooks Item which causes a FormCalc calculation to happen wherever it is used.
Trigger Items are just regular QuickBooks Items, but identifying them with a FormCalc calculation (i.e., an Action) makes them "trigger" the calculation on the form row(s) where those Items are selected. So trigger items give you control over where calculated results appear.
Item names to be used as Trigger Items are entered on the Trigger Items tab:
In the illustration at the top of this page, TOTAL WT. is a trigger Item for the Total Wt. Action. So wherever it appears, FormCalc will write a total for column 5 (the Extd. Weight column), like so:
FormCalc works by sending keystrokes to QuickBooks, reading and writing data to/from QuickBooks using the Windows clipboard and other "magic" provided by the Microsoft Windows API.
FormCalc does not rely on the QuickBooks SDK (Software Development Kit). This allows it to work with nearly all versions of QuickBooks, including non-U.S. versions and even very old QuickBooks releases.
As for invoking FormCalc while you're working in QuickBooks, you do that by pressing a "hotkey" of your choosing, usually the F10 key. When you press the hotkey FormCalc pops up a window over the current QuickBooks form:
In this window, you choose the calculations you want to apply to QuickBooks by selecting a Layout to use—you can click on a Layout name or press the Layout's corresponding number key (0...9). Then FormCalc goes to work, applying that Layout's calculations to the form.
