Conditional Logic detailed example

Here is a brief overview of conditional logic:

http://www.gravityhelp.com/documentation/page/Enable_Conditional_Logic

You can use it a couple of ways. For example, let's say you had a Question that offered yes and no options. Then you had two fields below the question that are enabled with conditional logic and one shows only show if selected yes and the other field shows if selected no. On the two fields in the Advanced tab on the field, you would enable conditional logic and apply the rule.

You can also do this with the submit button itself in the Form Settings tab. Let's say those two yes and no options were an agreement of some kind, if the user selects yes then the submit button shows. Let me know if you need any more guidance.

Hello! I'm new to Gravity Forms. I love the ease of use and setup, but am also finding good documentation for more tricky things hard to find.

My question about Conditional Logic is similar, but about the Submit button itself, based on choices made on three radio buttons.
These are the two scenarios, regarding form action after the user chooses payment options:
1. if user chooses the Bank Transfer or Check Payment Radio button - they get a confirmation page on form submission (that shows bank details and so on)
2. But If they choose 'Online Payment' radio button, then when they click Submit, they are sent to the third party payment gateway...

I cant seem to find any controls in the 'Edit Form Settings' to enable this kind of choice - the choice seems to be only 'Show or hide this button' based on previous choice. This is confusing, because if the Submit button is hidden, whats the point?

I mean, if conditional logic is used, there should be a way to have TWO submit buttons, only one of which shows up based on choices made, right?

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I realize one work-around is to have two forms: One for offline check payment, and one for Online.

In which case, my question is: is there documentation for php functions, or other code, on how to connect the online payment form to a third party payment gateway - apart from functions.php of my theme, I dont know which files to edit, or where to put the code,

Please help clarify this....thanks a bunch!

Is there any plan to include other payment gateways other than Authorize.net and PayPay? We are in Australia and use eWay. They are exceptional with developer support and eager to integrate to other platforms. So any plans??