Don't know which triggers to use, please help.

Question

Hi,
I'm a newbie to forms. I have a question about what triggers to use for my situation. I can't seem to find many examples for what I want to accomplish. I have tried using the online help (within forms) but sometimes they don't always have examples for their triggers).
Here's my scenario:
I have six items, five of which are text database items and one is a non-database display item (TOTAL). Each of the first 5 items holds a numeric value and the TOTAL item will store the sum of the previous 5. Of first 5 items, only the 4th item (POINTS) can be updated within the form (and I have set the Enabled propety to 'No' for the first 3 items). I have a function, TOTAL_COUNT, that will do the sum calculation and it works fine in a POST-QUERY trigger populating the value into TOTAL. However, what I'd like to do is anytime a user enters a new value in POINTS and then tabs or mouse clicks into the next item TOTAL, I'd like to call my function to update and display the new total value in TOTAL.
Does anyone know which triggers and/or code I can use to accomplish this? The code I use to call a function is:
:block_name.item := function_name(:parameter)
For your recommed triggers, can I just use that code to call my function or will I need any other syntax i.e. BEGIN...END, etc within the trigger body?
Any quidence would be greatly appreciated.
Thank you,
Eric

Answer 1

Hi!
1. Set Calculation Mode property of ITEM_5 to Formula.
Formula property:
nvl(:Block_Name.ITEM_1, 0) + nvl(:Block_Name.ITEM_2, 0) + nvl(:Block_Name.ITEM_3, 0) + nvl(:Block_Name.ITEM_4, 0)
OR
Function_Name(Param_1,... Param_N);
Have in view of, that the ITEM_5 data will not be saved in DataBase.
2. When-Validate-Item trigger is usfull when is necessary to store calculated item data in DataBase.
Rename you Post-Query trigger to When-Validate-Item.
Modify trigger: Store calculation result in the variable.
(Don't forget to round variable value!)
Then compare it with ITEM_5. If they are different - :ITEM_5 := var_name.
I prefer the first method.