Add SUPER+TAB switching mode that enables the user to switch applications via the Launcher

Bug Description

Add SUPER+TAB switching mode that enables the user to switch applications via the Launcher.

Desired functionality:
- Pressing SUPER+TAB opens the Launcher (if it is closed), and highlights the top icon in the Launcher.
- Each time TAB is pressed while super is held down the highlight moves one icon downwards.
- Holding down SHIFT at the same time as also holding SUPER and pressing TAB moves the highlight one icon upwards (SHIFT means the direction is reversed)
- The visual style of the highlight is exactly the same as the Alt+F1 highlight.
- Releasing the SUPER key performs the equivalent action to left clicking on the highlighted Launcher icon (e.g. if the app is not running, releasing the SUPER launches that app.
- In a multi-monitor environment, this interaction happens on the monitor with the currently focused window.
- It should be possible to escape this interaction at any time by:
-- pressing the 'Esc' key
-- clicking *anywhere* on the desktop
- pressing Tab (or Shift+Tab) at the bottom (or top) of the Launcher should loop the focus around to the opposite end

How does one escape from this? It looks like once you initiate super+tab switcher, there is no way to come out of it without launching something. There should be an easy way to come out of this mode without launching an item.

Another major issue I noticed with this is that the it's not circular. Once you go down to the bottom, you need to shift+tab to go all the way up. I think making this circular would really really improve the experience.

Also, if this is termed as a "switcher", then I think it should start from the current active app not from the top.

Should create separate bugs for these issues?

Owais: the escaping strategy has not been considered, however releasing over the BFB or the currently focused application simply does a "quite safe escape". Maybe making the Esc key to work as on Alt+Tab could be a nice feature.

About the circular thing, I'm waiting for design input, while about starting from the current app or not is a design decision (you should be always able to know what will happen after a fixed number of key press).

+1 to the circular mode. As for the starting point, I think we will have
to do some user testing.

Both have awkwardnesses (which is why we never mapped Alt-TAB into the
launcher). If you always start from the top, then it would be better to
use Super-<n>, which goes straight to your <n>'th launcher. If you start
from the current focus, then you need a mind which remembers the
launcher sequence perfectly :-)

Mark

Also, maybe starting from the BFB is useless considering that doing Super+Tab once just does the same of only tapping Super.

Circular (bug #919018) mode and Escape key support (bug #919019) added in branch lp:~3v1n0/unity/super-tab-improvements. I also suggested to John Lea about using the focused icon as starting point, but I understand the fact that both solutions aren't perfect.

Maybe we should add an option to allow to switch the behavior to the users.

An option for starting point would be nice

No, an option for starting point would be a marginal benefit, extra
code, extra tests. Let's user test, pick the better option, and use only
that please.

This bug was fixed in the package unity - 5.2.0-0ubuntu1

---------------
unity (5.2.0-0ubuntu1) precise; urgency=low

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