A script handler you can implement to override standard MoneyWorks behaviour.
Automatically called: Whenever the contents of a field changes. This includes typing a a character into an edit field; clicking a checkbox; changing a popup menu.
Use for: Reacting immediately to a control change or as a chance to call AutoFill on a code field
Specific Naming: You can and should implement an Itemhit handler that is specific to the particular window ID and itemID of interest. e.g. Itemhit:<WindowId>:ItemID:TransactionType (the last of these applies only when the WindowID is F_TRANS)
ItemHit handlers for editable list cells can have more detailed specific naming (down to the column name of the active cell) and will receive additional parameters (namely the list handle, the current row number, and the current column number). e.g.
on ItemHit:F_TRANS:L_LIST:DI:Location(winRef, listId, listHdl, rownum, colnum) for an ItemHit handler that responds only to kepresses in the location column of Debtor Invoices. Note that for the transaction entry form, you must supply the type specifier. Note also that due to backwards compatibility, the list is identified by its underlying identifier L_LIST rather than a tab name like By_Item. This does have the benefit that you can respond to, eg, the job column in either the By_Item or By_Account tabs using the same specific handler (since v9.0.9).