Subsurface mobile: delete and sync operations.

[Dirk Hohndel]

> On Jul 19, 2017, at 4:11 AM, Willem Ferguson <willemferguson at zoology.up.ac.za> wrote:
> 
> I must preface this expressing my pleasure in seeing what is happening with Subsurface-mobile version 2. The enormous effort that is going into this and the incredible difference that it makes to the usability of the program. I am privileged to be associated with this team that is creating a remarkable piece of software.
> 
> I experience that there are fundamental problems with manipulating dive lists on the mobile platform.
> 
> 1) See screencast at
> 
> https://www.dropbox.com/s/47m9ujbzancuxen/2017_06_24_11_28_30.mp4?dl=0
> 
> using 4.6.4.443. This playback speed is at a THIRD of the live speed.
> 
> View dive list.
> 
> Delete a dive
> 
> Go back to dive list
> 
> Select another dive and hit delete button at bottom.
> 
> Display goes to *previous deleted* dive and the second dive is not deleted at all. Looks like delete sequence is not even started.
> 
> Hitting the Android Back button (to get back to the dive list) crashes the program.
> 
> Fortunately, upon restart of the program, no dives are deleted.
> 
> I can supply adb logcat if required.

I have now been able to reproduce one of these "delete - divelist goes weird" bugs. I still don't understand why the model gets confused, but at least now I can work on it.

> 2) When deleting a dive/profile from the button at the screen bottom, the undo option only shows up for about 1 second. This is way too short for an unprepared user to respond appropriately. And then the dive is (theoretically) permanently deleted. Extremely user-unfriendly. The interface would be much more safe if the 1-second button rather said: "Confirm delete". Noticed the steps in Github that are required to delete a repo? You must really be convinced to do this in order to delete a repo, no way of doing that accidentally. I am pretty conversant with the mobile UI and on a few occasions my finger has managed to accidentally stray to the dustbin under a dive profile. And then the "Undo" button comes up, out of the blue, and I am so startled that I do not respond in time. Dive gone.

The pattern of confirming an action is something that is not well liked in mobile apps. I am pretty sure we had this discussion here a while ago. I agree that it's way too easy to delete a dive. Of course, that dive isn't really gone (thanks to our git storage), but that's no consolation for a regular user.

I'm not sure what to do about this. Davide, you are our resident UI guru... what do you think?

> 3) I intentionally deleted four dives from my dive log (using dive list and red button) in order to test the delete option. Then I tried to regain them by doing a "Save to cloud" from my desktop. Nice, divelog saved. Then I do a "Sync with cloud" on the mobile but the four dives do not come back. No way of get them back, except by uninstalling Subsurface-mobile on Android and doing a complete reinstallation, re-initialising the cloud credentials and reloading the divelog from scratch. My four dives are back.

You'd think that would work, but it doesn't because of the way git merges the operations. We need a UI to bring back deleted dives. It's not really hard to do, it's just something someone needs to implement.

> I am just thinking how an unfamiliar user will struggle with this interface. My firm suggestions are:
> 
> a) On Android, the "Sync with cloud" tries to be too clever and as far as I can see does not succeed. As user I would be much more happy if I had complete control with two more options: "Save to cloud" and "Load from cloud". These are unambiguous with clearly predictable results.

The way git works it's not that easy. Yes, it's easy to implement "forget everything I've done and go back to what's on the server". I actually started working on that and then got side tracked. I should have a branch that has the beginnings of that somewhere. But "save to cloud" and ignore changes from the other side is not something that I'm keen to implement. That's basically a force push and that will make any other Subsurface instance that is connected to the cloud storage decidedly unhappy. So this needs a bit more thought.

> b) Make the delete dive action more safe. Dive data are valuable, often with significant time spent in writing notes, specifying cylinder pressures (that are lost upon delete) and the like. One does not want to lose a dive accidentally.

Agreed. I'm just not sure what the best user interaction for that would be.

/D