803447 - During app-to-app switching, if the switching canceled by the user, or one of the app crashes, the transition will never complete

Status: VERIFIED FIXED

(Firefox OS Graveyard :: Gaia, defect, P1)

Description

[Dave Townsend [:mossop]]

Apparently there is a way to bring up preview cards of running apps (like in WebOS). I don't know how you do it, but somehow I managed it and then somehow they got stuck there and now I am panning around in the homescreen despite these cards hovering over the top. They are just visual, tapping acts as if they weren't there.

Comment 1

[Dave Townsend [:mossop]]

Only the notification bar appears over the top of them and it seems I can't get rid of them without restarting the phone.

Comment 2

[Chris Lee [:clee]]

This sounds like a usability issue.

+Josh/Patryk for comment

Dave is having a hard time figuring out he invoked the task manager, which means he also had a hard time figuring out how to close it.

Comment 4

[Dave Townsend [:mossop]]

I don't think this is a duplicate, but 796238 talks about being able to interact with the task manager, but in my case I couldn't.

Comment 5

[Dave Townsend [:mossop]]

Now that I've learnt how to open the task switcher I'm even more sure this isn't a dupe

Comment 6

[Josh Carpenter [:jcarpenter]]

It sounds like Dave encountered a bug. Normally users can easily exit the mode by 1.) selecting a card, or 2.) pressing the Home button. I don't think there's a usability issue here.

Comment 7

[Ben Francis [:benfrancis]]

I'm not entirely convinced this isn't a dupe, but it is bad enough to block because it prevents you using the task switcher properly.

Comment 8

[Dave Townsend [:mossop]]

Attachment: screenshot

Saw this again today and here is a screenshot. I think when its in this state as far as the phone is concerned the task manager is closed, it just left behind the painted apps somehow.

You'll note that unlike when using the task manager normally the background isn't dimmed. I can also press where the big white box is that represents a running app and that tap goes through and presses whatever is underneath it, so aside from visually this state doesn't affect operation of the phone. Heck I can even open the task manager in this state and it appears underneath the stuck apps, I can make use of it and close it and the stuck apps remain there.

Comment 9

[Dave Townsend [:mossop]]

When in this state opening apps shows them appear in the white box and then expand to fill the screen. Pressing home makes them shrink down to the size of the white box and then just go totally white.

I've noticed in some cases switching from one app to another will briefly show a task display like this so I wonder if it is something to do with that breaking?

Comment 10

[Dave Townsend [:mossop]]

(In reply to Dave Townsend (:Mossop) from comment #9)
> When in this state opening apps shows them appear in the white box and then
> expand to fill the screen. Pressing home makes them shrink down to the size
> of the white box and then just go totally white.

I should note that once expanded the white box (and side of calculator) appears over the top of the app, but again doesn't interfere with the operation of the app.

Comment 11

[Chris Jones [:cjones] inactive; ni?/f?/r? if you need me]

Z-ordering issue perhaps?

Comment 12

[(inactive after 6/18) Alive Kuo [:alive]]

(In reply to Dave Townsend (:Mossop) from comment #9)
> I've noticed in some cases switching from one app to another will briefly
> show a task display like this so I wonder if it is something to do with that
> breaking?

I think you are talking about web activity which disposition is 'window'.
But I couldn't reach your state by any operation, could you please provide more clear Steps to Reproduce? Much thanks.

Comment 13

[(inactive after 6/18) Alive Kuo [:alive]]

(In reply to Chris Jones [:cjones] [:warhammer] from comment #11)
> Z-ordering issue perhaps?

From the images Dave attached, the semitransparent overlay and app name is hidden, only the images are shown.
And he said he could play the homescreen as if the images are not there.
I guess this is a rendering issue. But I never saw this.

Comment 14

[Tim Guan-tin Chien [:timdream] (please needinfo)]

Update the title to explain what's going on, and take the bug.

Comment 15

[Tim Guan-tin Chien [:timdream] (please needinfo)]

Ah, I've already took the issue :-/

Comment 16

[Tim Guan-tin Chien [:timdream] (please needinfo)]

Sorry, my bad, unrelated

Comment 17

[Mike Connor [:mconnor]]

Blocking retriage: Not blocking on single-user-reproducible issues.  This seems bad, but no other reports of this have come in.  We'll reconsider blocking if/when that happens.

Comment 18

[[e-mail] [:onecyrenus]]

https://bugzilla.mozilla.org/show_bug.cgi?id=805944

Comment 20

[Dave Townsend [:mossop]]

Per the duplicate, re-requesting.

Comment 21

[Tim Guan-tin Chien [:timdream] (please needinfo)]

I am worry that starting fixing this bug before https://github.com/mozilla-b2g/gaia/pull/5888 is merged will break it. So I will wait for it while working on a fix on top of those commits.

Comment 23

[Tim Guan-tin Chien [:timdream] (please needinfo)]

Attachment: Github: https://github.com/mozilla-b2g/gaia/pull/6180

https://github.com/mozilla-b2g/gaia/pull/6180

This patch attempts to fix the app-to-app transition by changing the underlining method we do transitions, instead of delivering a fix that pile things on the top of the current code. (code removed > code added!!)

Currently, depend on the unpaint state, Window manager might transition the frame or the sprite; maintain the code to control the state of both of them, especially and handling interruptions is tough. This patch fix that by removing the use of sprites (both #windowSprite and .windowSprite) and always transition on the actual frame.

For unpainted frame, we will set the background of the frame to the screenshot blob stored in the database; since an unpainted frame is transparent, we ended up transition the screenshot (the desired effect). As soon as the firstpaint happens, we reset the background and continue the transition with actual frame content.

The only intend impact to the transition animation is the crossfade between frame content and the screenshot -- that won't happen anymore; it would just suddenly switch when firstpaint happens. Some app flashes white briefly during the switching between two because firstpaint doesn't guarantee the app is loaded -- that can be improved on individual apps on bug follows.

Comment 24

[Tim Guan-tin Chien [:timdream] (please needinfo)]

https://github.com/mozilla-b2g/gaia/pull/6180

Merged.

Comment 29

[Deepa Subramanian]

verified on Unagi Build id:20130102070202