Android: Restore download snackbar/logic for 2 zoomlevel-"download full size" offer

[AndyScherzinger]

The image preview allows for downloading the full-size image if the user pinch-to-zommed enough.
A snackbar shows up offering the full-size download.

For consistency I suggest that this also happens if the users double tap to zoom-in.

[ardevd]

@AndyScherzinger could you provide me with a step by step instruction on how to reproduce the issue and a description on what's supposed to happen? I've done some side-by-side tests with the PR and with the stable version from Google Play and I cant really see any difference.

[AndyScherzinger]

@ardevd: Sure thing :)

1. open an image which hasn't been downloaded --> shows a preview image (lower resolution) from server
2. zoom-in two times --> a snackbar should show up asking if you want to download the full-resolution images

In the past I think the zoom-to-download part has been implemented via #1710

[ardevd]

@AndyScherzinger hmm, I can't really replicate this behaviour with the app before my PR. Firstly there was only one zoom level. Secondly, I don't get a snackbar message at all when zooming in.

The exception seems to be png files with transparent backgrounds where I immediately get a snackbar message saying "No resized image available. Download full image?"

So I can't really see any difference here before and after my PR, but I might be missing something.

[AndyScherzinger]

Maybe @tobiasKaminsky can clarify how to reproduce the behavior tomorrow.

[AndyScherzinger]

@ardevd My mistake... the snackbar for full-size image download still shows up... I could reproduce it even with your introduced photoview via: pinch-to-zoom-in "like crazy"... then the snackbar comes up :)

[ardevd]

So should we close this issue or rephrase it? :)

[AndyScherzinger]

I rephared it :)

[AndyScherzinger]

@tobiasKaminsky @ardevd for whatever reason, this lint issue comes up since today:

<string name="resized_images_download_full_image">Download full image?</string>

is now an unused resource, I then checked the pinch-to-zoom-to-download-snackbar again and it doesn't show up anymore! :warning:

[ardevd]

@AndyScherzinger That's odd. I'm pretty sure I didnt touch it and it worked fine after #2593 so there must have been a merge after that. Time to check the logs ;)

[ardevd]

@AndyScherzinger R.string.resized_images_download_full_image was used in TouchImageViewCustom.java, so that explains why its not used anymore. However, a similar message did show up after #2593 was merged. I'll look into it.

[AndyScherzinger]

Thanks for the clarification @ardevd, like I said for some reason even though it worked after your initial PR ist somehow stopped working (for me at least). Strange... :/

[ardevd]

I can confirm the same. I'm developing a new implementation for it now. Double tapping the image will bring up the snackbar message prompting the user to download the image.

[ardevd]

However, perhaps we can do this in a more elegant user? As a NextCloud user for years, I never noticed the prompt until working on #2593. Perhaps we can expose the feature in a smarter way? Or do we need this feature at all? Downloading the image can easily be done using the three-dot menu

[AndyScherzinger]

The feature isn't easy to discover while I personally don't have a good idea on how we could improve its discoverability or if like you said we don't need it at all since people can use the menu to download while the snackbar logs the Yeses and then auto-downloads so it has some more logic to it than just prompt+download.

What do you think @tobiasKaminsky (original author), @mario and @nextcloud/designers ?

[ardevd]

I'm generally in favor of scrapping the feature as it doesnt really make sense from a UX perspective in my opinion and acts more like a random gesture control that most user will at best accidentally stumble upon. Also, since it's not a UX pattern used anywhere else, it's not exactly a defining feature.

But interested to hear what you guys think

[tobiasKaminsky]

As far as I remember it was an idea coming up while limiting resized images to zoom factor 2x, otherwise images might get too blurry and this was something @jancborchardt wanted to avoid.
In fact it is only a shortcut for downloading, but case sensitive.

I have no hard feelings above this at all…
Let us have at least two additional opinions, best would be one from @nextcloud/designers, and then just do what the majority decides :-)

[jancborchardt]

Yes, as @tobiasKaminsky said it’s a kind of a shortcut for downloading. I think it’s quite useful, only coming in when you need it.

@ardevd if you never noticed that or never needed it, that’s good too, because it’s a progressive enhancement shortcut.