Calling functions from Grid

[Jberry]

Hello all,

I have a grid and I want to have one of the fields be a calculated field but it's not a straightforward calculation like Qty * Price. I'd normally do it in the Client side Properties but that looks like I need to write JavaScript and I know zero about that.

I have a table (DBF) that looks something like:

Quantity Price
100-199 $100
200-500 $ 75
501-1000 $50

In my Grid have a field QTY and PRICE. If the user enters a QTY < 100 then the TTL = QTY * PRICE, but if they enter a QTY of say, 245 then I need to lookup the price in the table and return $75. In Access I could create a Query and insert a Function and return the correct price but I don't know how to do that in A5.

So the question is:

a) Where do I create the XBasic code to retrieve the correct prices.
b) How do I call the function from the Grid to calculate those prices.

Any help, ideas, pointers much appreciated.

Thanks
-John

[Jay Talbott]

Re: Calling functions from Grid

Let's start with the psuedocode:

upon leaving the quantity field, create an Ajax callback
- the Xbasic for the Ajax callback would be a script that determines the correct price, and puts the price into a javascript variable
- the javascript that the Xbasic returns would place the price in the Price field
the TTL field can be a calculated field, regardless of the pricing structure, because the formula would always be Q * P

While the javascript may seem daunting, I always follow the Gwenn rule: Chunk it down

Start by creating a button that places an arbitrary, predetermined price into the price field
Then create a variable and populate the variable and place the price in the price field
Then move that javascript to the Xbasic function

If you try it all at once, you will just frustrate yourself.
I hope this helps.
Jay

[Jberry]

Re: Calling functions from Grid

Hi Jay,

Thanks for the reply...you lost me at AJAX callback :)

You don't have a quick and dirty example do you by any chance that you could share?

-John

[Peter.Greulich]

Re: Calling functions from Grid

Typically you would add a button to your grid. Go to the button's OnClick event/Action JavaScript/Ajax callback. Give the function a name. Click "create function prototype. Click "copy to clipboard". Click "Open xbasic functions declarations". Paste the code. Read through the supplied function help. There's more, but that should get you started.

[Jberry]

Re: Calling functions from Grid

Thanks to both, I'll give it a shot and post back.

-John

[Jay Talbott]

Re: Calling functions from Grid

John,
Can you write a script that would grab the correct price given a specific quantity?
If so, write it and paste it on the board, please.
Jay

[Davidk]

Re: Calling functions from Grid

Have a look here, John... video # 56 should help, along with other videos that reference the Ajax callback.

In short, and I hope I have this right, these Grids are Ajax Grids (Ajax being the programming language and methodology that Alpha uses). The Callback is... exactly that... a call, back to the server to do some work.

http://news.alphasoftware.com/v10preview/videos.htm

Correction: AJAX is a methodology... however, not a programming language.

[Jberry]

Re: Calling functions from Grid

Excellent. Thanks everyone.

[Jberry]

Re: Calling functions from Grid

I'm following video 56,taking it in chunks, and making use of Debug(1) and now it's starting to make sense. I'm not out of the woods yet and may post back with more questions but wanted to thank you for the help.
-John

[madtowng]

Re: Calling functions from Grid

As an alternate option, have you considered Clientside Calculated field expression ?.

The code listed below calculates Price.

if(Qty >=100 and Qty <=199,100,if(Qty >= 200 and Qty <= 500,75,if(Qty >=501 and Qty <= 1000,50,"")))