Populate a Text Box froma text box

[StefaniaO]

Hi to all, I have two Text boxes and a secondary data source (xml file), and
I wish to populate the second based on a value from the first text box,
wwhen this changes.
The value in the first text box is a key to catch a value from the secondary
data source.
I try to do this by using rules (default values, rules on open form) and I
use the value on the first text box as a filter. But this doesn't work.
Can anyone help me ?

 

[S.Y.M. Wong-A-Ton]

I think you're almost there. Are you using the rule when the form is opened
to set the value of the second text box? If so, use that rule to set the
value of the first text box to its default value and create a rule on the
first text box to set the value of the second text box using the secondary
data source and filter as you've already done.