Manually loading XML data into XForms

[Nepomuk]

Hello everybody!
I'm pretty new to XForms and doing a project with XForms and eXist, so I have an XML file as a database. The problem I'm having is the following:

My XForms document looks something like this:

...
  <xf:model version="1.0">
   <xf:instance id="data-instance" src="data.xml" xmlns="">
    <Data>
     <FirstName/>
     <LastName/>
    </Data>
   </xf:instance>
   <xf:submission id="read-from-file" method="get" action="http://localhost:8080/exist/rest/db/eXist_test/data.xml" replace="instance" instance="data-instance"/>
   <xf:submission id="save-to-file" method="put" action="http://localhost:8080/exist/rest/db/eXist_test/data.xml" replace="instance" instance="data-instance"/>
  </xf:model>
...
  <xf:input ref="/Data/FirstName"><xf:label>First Name: </xf:label></xf:input><br/>
  <xf:input ref="/Data/LastName"><xf:label>Last Name: </xf:label></xf:input><br/>
  <xf:submit submission="read-from-file"><xf:label>Load</xf:label></xf:submit>
  <xf:submit submission="save-to-file"><xf:label>Save</xf:label></xf:submit>
...
 

and my XML document looks like this:

<Data>
 <FirstName>Peter</FirstName>
 <LastName>Parker</LastName>
</Data>
 

Now, when the document loads, it loads the values from the XML file into the Document, ditto when I click on "Load" and when I click on "Save" it submits the changes to my XML file. So far so good - but now I want to be able to add new tags to the XML file via the webinterface (e.g. <MiddleName>). When I have further paths in my XForms document, they just won't display, unless they belong to a different instance (which isn't a choice I guess, because it will only submit the data of one instance when I save).

My idea was therefore to cut out the src="data.xml" part in the instance description and just load the entries manually. Also, the read-from-file submission would have to be changed. However, I can't seem to be able to find anything like that online. Any ideas or suggestions, how do do this differently?

Greetings,
Nepomuk

[Nepomuk]

Does nobody have an idea? Any bit of help would be great.

Greetings,
Nepomuk

[Dormilich]

sorry, but I only glanced over XForms. you may be able to change the XML by JavaScript, though I didn’t try that either.

[Nepomuk]

I just had another thought, maybe this could work, though I have no idea how to implement it:

Let's assume, when I want to add a new tag, I click on an "Add" button. What happens then, is that a different instance is selected for saving and this instance gets a copy of the data from the original instance plus the new stuff that's supposed to be added. So, the new question would be: How do I copy data from one instance to another?

Greetings,
Nepomuk