I have a pilot thing working which parses an XML file, displays it in a syntax-highlighted editor, and simultaneously displays its DOM tree in an expanding tree widget and a list of its xml:ids (with the first 30 characters of the element's text) in a list view. This is pretty good, but I know in my heart that what I really need is a model/view architecture whereby the QDomDocument is the model, and these three views are all synchronized so that when you click on (say) an xml:id in the id list, the dom tree opens and highlights the corresponding element, and the editor scrolls to, and highlights, the same element. QT's model/view stuff hurteth my brane mightily, but I managed to understand it for long enough to write the little SVG resource applet, so I'm sure I can do it again.