I have to write a desktop application to edit data stored in a XML file. The format is defined by a XML schema file (.xsd). The format is quite complex.
Are there tools
It's worth taking a look at Jaxfront which is able to consume an XSD and generate a form (including HTML). You can also supply an instance XML document for it to load into the GUI, and save out instance XML documents too.
I tried it with one of our fairly complicated XSD's and it worked pretty well.
Sadly it's written in Java - I'm still looking for something which can generate .NET web forms or XAML/WPF! In fact even XFORMS would be good.