Playframework [Scala]: Binding a list/seq to the controller - html

Question

I am trying to bind a list of input items on my html page to my controller.
My form is defined as:
def clientForm = Form( tuple(
"clients[]" -> seq( tuple(
"firstname" -> text,
"lastname" -> text) )
) )
In my HTML I have tried the following:
#b3.text(thisForm("clients[0]"), '_label -> "first client", 'value -> "('John','Snow')")
#b3.text(thisForm("clients[1]"), '_label -> "second client", 'value -> "('Frank','Carson')")
I have also tried:
#b3.text(thisForm("clients[0].firstname"), '_label -> "first client fistname", 'value -> "John")
#b3.text(thisForm("clients[0].lastname"), '_label -> "first client lastname", 'value -> "Snow")
#b3.text(thisForm("clients[1].firstname"), '_label -> "second client fistname", 'value -> "Frank")
#b3.text(thisForm("clients[2].lastname"), '_label -> "second client lastname", 'value -> "Carson")
In debug mode upon POST I can see that these values get bound to the form within the controller:
val boundFrom = inForm.bindFromRequest
But when I boundForm.fold mapping to clientForm the values to not map correctly to my "clients[]" element.
I'm at a loss and have spent ages looking for the answer to no avail.
Any help greatly appreciated
EDIT:
Here's a screenshot in debug mode. The values are being bound to the form but then do not get assigned.
Debug screenshot

Answer 1

Please note that your form definition can be as following -
def clientForm = Form(
single(
"clients[]" -> seq(
tuple(
"firstname" -> text,
"lastname" -> text
)
)
)
)
Then you second way of writing template is correct as you can see in documentation here https://www.playframework.com/documentation/2.6.x/ScalaForms#Repeated-values
Now what you will get when you fold this form is that a seq of tuples and you can use it like following -
clientForm.bindFromRequest.fold(
error => // Handle error
clients => {// this clients is of signature Seq[(String, String)]
clients.map{client => logger.log("First name: " + client._1 + ", Last name: " + client_2)}
}
)
Please note that you have to use tuple ._1 and ._2 to access your first name and last name here. As you are getting a tuple (String, String) not a Map[String, String] here.