PyGTK: Need help scrolling multiple TextViews together

Question

I am trying to write a text viewer widget with PyGTK that displays line numbers alongside the main viewing window. Of course I want the line numbers and main window to scroll in sync with each other. I can't figure out how to get this to work, though. Right now I am doing this. TextViewer is a subclass of HBox that creates the two TextViews and packs them into itself under the attribute names linenums and mainview.

self.textviewer = TextViewer.TextViewer(self.toplevel)

sw = gtk.ScrolledWindow()
sw.set_vadjustment(self.textviewer.mainview.get_vadjustment())
sw.set_hadjustment(self.textviewer.mainview.get_hadjustment())

sw.add_with_viewport(self.textviewer)

sw.set_policy(gtk.POLICY_AUTOMATIC, gtk.POLICY_AUTOMATIC)

If I take out the two set_Xadjustment lines, then the embedded TextViews' scroll_to_mark function doesn't work, which isn't acceptable for my application. With them in, the main text window scrolls twice as quickly as the line number window, and vice versa if I set the ScrolledWindow's adjustments to those of self.textviewer.linenums. I strongly suspect that this is a bug. I also tried setting up the viewport myself and setting its adjustments to those of one of the TextViews, but again the scroll_to_mark functions stop working. How can I synchronize both TextViews to scroll as one, so that any scrolling changes to one of them equally affect the other?

EDIT: Here is the code in my main application where I set up the widget.

self.textviewer = TextViewer.TextViewer(self.toplevel)

sw = gtk.ScrolledWindow()
#These are the lines that toggle between the two problems when (un)commented
sw.set_vadjustment(self.textviewer.mainview.get_vadjustment())
sw.set_hadjustment(self.textviewer.mainview.get_hadjustment())

sw.add_with_viewport(self.textviewer)

sw.set_policy(gtk.POLICY_AUTOMATIC, gtk.POLICY_AUTOMATIC)

Answer 1

I'm having difficulty understanding exactly how you've got the two gtk.TextViews packed in the HBox. Are they both packed in separate gtk.ScrolledWindow that are then packed inside of the HBox which is then packed into another gtk.ScrolledWindow(The one mentioned in your post)? From what it sounds like to me, both of these gtk.TextViews are packed in their own gtk.ScrolledWindow within your TextViewer wrapper widget.

If this is the case, a simple solution to your issue, granted that the two gtk.TextViews are the same height(so the line numbers line up with the main view), I suggest simply packing them inside your Hbox without ScrolledWindows. Then you can use your code above, adding them that ScrolledWindow and the viewport will move the two collectively as if they are one widget.

If this isn't your issue, could you please supply some more information about your TextViewer wrapper, and maybe some more sample code?

Also: You may be interested in gtksourceview. With the gtksourceview2 package, you get an instance of the View widget:

import gtksourceview2
view = gtksourceview2.View()

Answer 2

You might want to check how it is implemented in Meld. In particular, the filediff code (search search for sync there).