Gtk3 Scrolled Window's horizontal scrollbar not working properly

[Daniel Kasak <d j kasak dk gmail com>]

I've just noticed something strange. In Gtk3, my scrolled windows aren't detecting the width of a treeview properly.

If I set their Horizontal Scrollbar Policy to 'automatic' ( I'm using Glade, by the way ), I never get a scrollbar, and I can't access things which don't fit horizontally inside the treeview. If I set the policy to 'always', I get a scrollbar, but it acts like everything fits ... ie scrollbar covers the entire horizontal area, and doesn't allow scrolling.

In the attached screenshots, the 1st one is with the default column widths my app has chosen. The 2nd screenshot shows after resizing the columns down, so more will fit. In both cases, the horizontal scrollbar refuses to allow scrolling.

Vertical scrollbars appear to work fine

Does anyone know why this would be? I can try to build a simple example app if that's needed. At the moment, this is app is using the Gtk3 port of my DBI Datasheet class - it's showing values I've pulled from a solar inverter.

Dan

Attachment: scrolled_window_1.jpg
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Attachment: scrolled_window_2.jpg
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