Document viewer Field Help

This is pretty much as straightforward as adding a!buttonArrayLayout() on the interface that submits the form, then the form will chain back to itself - typically with a decision node to determine if they are asking for a preview, or submitting/canceling the form to move the process:

A quick and dirty sample interface would be something like below with 2 inputs for document (document), and navigation (text):

a!localVariables(
  local!document,
  /* there are more graceful ways to check for doc existance */
  local!documentExists: not(tostring(ri!document)="[Document:]"),
  a!formLayout(
    label: "Document Upload / Preview",
    contents: {
      a!columnsLayout(
        columns: {
          a!columnLayout(
            contents: {
              a!boxLayout(
                label: "Select Document",
                style: "ACCENT",
                contents: {
                  a!sideBySideLayout(
                    items: {
                      a!sideBySideItem(
                        item: a!fileUploadField(
                          value: local!document,
                          saveInto: local!document,
                          maxSelections: 1
                        )
                      ),
                      a!sideBySideItem(
                        item: a!buttonArrayLayout(
                          buttons: {
                            a!buttonWidget(
                              label: "Preview Document",
                              value: "PREVIEW",
                              saveInto: {
                                ri!navigation,
                                a!save(ri!document,local!document)
                              }
                            )
                          }
                        )
                      )
                    }
                  )
                }
              )
            }
          ),
          a!columnLayout(
            contents: {
              a!boxLayout(
                label: "Select Document",
                style: "ACCENT",
                contents: {
                  a!documentViewerField(
                    showWhen: local!documentExists,
                    document: ri!document
                  ),
                  a!richTextDisplayField(
                    showWhen: not(local!documentExists),
                    value: {
                      a!richTextItem(
                        text: "You must click Preview on the left for the document to be viewed",
                        style: "EMPHASIS"
                      )
                    }
                  )
                }
              )
            }
          )
        }
      )
    },
    buttons: a!buttonLayout(
      primaryButtons: {
        a!buttonWidget(
          label: "Submit",
          validate: true,
          submit: true,
          value: "SUBMIT",
          saveInto: {
            ri!navigation,
            a!save(ri!document,local!document)
          }
        )
      },
      secondaryButtons:  {
        a!buttonWidget(
          label: "Cancel",
          validate: false,
          submit: true,
          value: "CANCEL",
          saveInto: ri!navigation
        )
      }
    )
  )
)

Just to note, this is a continuation of the other thread on the topic.