[regression] Dash - When a drag and drop action from the Dash is abandoned by dropping the item back into the Dash, all the Launcher icons 'flicker' as they suddenly loose their tinting for a brief moment

[John Lea]

When a drag and drop action from the Dash is abandoned by dropping the item back into the Dash, all the Launcher icons suddenly become illuminated

To reproduce:

1. To reproduce this bug you must be using duel monitors, set up to extend the desktop (e.g. NOT mirror)
2. Open the Dash on one of the monitors, and start to drag an item
3. Drop the item back into the Dash to abandon the action.

Current incorrect behaviour in 12.10: either:
a) All the Launcher icons suddenly loose their tinting for a brief moment (e.g. all the Launcher icons flicker)
b) After the drop action has been perfomred, all the Launcher icons loose their tinting

A screencast of this bug is attached, see Launcher_flicker.ogv

Note this screencase was made on the 10th Oct 2012, with a fully up to date vanilla install of Quantal

Correct desired behaviour as currently implemented in 12.04: When the drag and drop action is abandoned, the valid drop receptacles return to the tinted state. The Launcher icons which were not valid drop receptacles do not change of flicker in any way, they remain in the tinted state.

[Andrea Azzarone (azzar1)]

Can you make a video of the bug. I cannot reproduce here.

[John Lea (johnlea)]

@andyrock; I've attached a screencast. When making the screencast I discovered that this bug only occurs on multi-monitor systems, I have updated the bug description accordingly.

[Nick Dedekind (nick-dedekind)]

So, this happens because the different launchers all share the same launcher model (ie the icon backend), which is where the saturation state exists; but the "overlay enabled" & hover states exists on a per launcher basis.

1) When the use cancels a drag, we reset the saturation status to the intended value.
2) However, we do this in both launchers, one of which "overlay enabled" is false, causing the icons to saturate.
3) Which monitor you have the dash open on will give different results. First will leave the icons saturated, second will flicker them as they briefly turn saturated, then desaturated.

Question: Do we not wan the overlay on all monitors if the dash/hud is open?

Either we need to have the hover/overlay state shared between the model, or we need to have icon states (quirks) per launcher, or there needs to be some hacky-jiggery-pokery for checking which monitor we're operating on.

[Stephen M. Webb (bregma)]

Fix Released in Unity Unity 7.2.0.