Network config page is jumpy

[Mark Shuttleworth]

The network configuration page should not re-flow when links come up or config changes (such as IP addresses being assigned).

We do want the network config page to be dynamic, in the sense that link changes are reflected in the display, address assignments as well. But we don't want that to cause the shape of the page - the number of lines taken up - to jump around. Focus should be stable on the screen.

To achieve this, the layout of each interface stanza needs to be designed so that a fixed number of lines is used, with a one-line gap between each interface. Changes in the state of an interface can then be reflected in the screen without causing the total number of lines to change.

It may happen that state changes result in focus being forced to change, for example if a link drops because someone unplugs the cable. Nevertheless the focus should stay on that interface in some way.

[Michael Hudson-Doyle (mwhudson)]

This all makes sense, although I worry about the amount of space IPv6 addresses can take up. There will necessarily be some jumping if NICs appear or disappear (e.g. a USB NIC gets plugged or unplugged) but that's an edge case I think. It's probably worth getting some input from the design team.

[Michael Hudson-Doyle (mwhudson)]

The new network screen, while not perfect, does not have this particular problem.