Explain to the user the difference between Refresh and Update, or eliminate Refresh

[Ronan Jouchet]

Hi! Your extension works great for me. One thing though:
 - I get what 'Update' does, from the name it must be something similar to "apt-get update"
 - Similarly, 'Upgrade' must be the equivalent of "apt-get update"
 - But what's 'Refresh'?

Looking at the source, it seems _actionUpdate() just calls _actionRefresh(), followed by a call to RefreshCache. And on the contrary, Refresh doesn't call RefreshCache. If Refresh doesn't refresh anything, what is it good for, then? I guess that could be clearer if you explain here the API nuance, but I think it would be great to add a few words to explain the difference to non-experienced users in a few simple words. Maybe you could add this text in the Settings section, under "Update Interval"?

Or if the "Refresh" action is just internal refresh of your extension data, maybe it could be eliminated by auto-refreshing?

Thanks for the great job you already did! :)

[mbady (aegirxx-googlemail)]

Hi Ronan,

the 'refresh' action queries the underlying packagekit daemon about the package caches state (the list of the updateable packages and their metadata).
If the 'update' or 'upgrade' action is fired it can be assumed that after finishing the action some change in the state of the systems package cache occured.
So the extension fires this action and gets the new state.

If you manage the updates just with the extension there's clearly no need for an extra 'refresh' button. But if some cache change is caused by an external
action (like typing 'sudo apt-get update' or 'sudo apt-get ugrade' on the terminal) there's no way (afaik (with packagekit)) to get the extension informed about that change.

For this reason i'd added the 'Refresh' button. I know that this solution isn't very satisfying but it was the quickest :)