[Bug 35509] Enabling network interface fails if changes to network settings have not been applied

[Krzysztof Lichota]

Public bug reported:
https://launchpad.net/malone/bugs/35509

Affects: kde-systemsettings (Ubuntu)
       Severity: Normal
       Priority: (none set)
         Status: Unconfirmed

Description:
Prerequisites: local network without DHCP

Scenario:
1. Go to System settings->Network
2. Click on eth0->Configure interface...
3. Add static IP address to network interface
4. Click OK
5. Click on eth0 and choose "Enable interface"

Enabling interface fails (the interface goes back to "disabled" state
after a second or so.

In order to make enabling work, user must first click on "Apply", then choose interface and choose "Enable". It is counter-intuitive. 
If applying changes is necessary, module should do it automatically or ask user: "Enabling interface requires saving changes - do you want to save changes now?" or something like that.