Images don't display instantly

[Kirk_Masden]

Hi!  I've set "Store content for offline use" to on (see image below).  My motivation for doing so is to make certain images that are part of the user interface (that is, what I added to the app to show to users, not what a user has added) load instantly:

Sadly, the images don't load instantly and if I turn off the WiFi and mobile data on my phone they don't load at all.  I think the problem may be the way in which I'm trying to call up the images:

=concatenate("https//mywebsite.com/appsheet/",[periodically changing number],".png")

So, the resulting URL would be something like this:

https//mywebsite.com/appsheet/5.png

There are only 10 possible images (1 to 10) and I have put all ten in another part of my app to make it read them in instantly when the time comes.  But, alas, it's not working.  The images display but there is a delay for them to be read in -- defeating the purpose of my setting the app to "Store content for offline use."

Questions: Is it my use of Concatenate() that is causing the problem?  If so, is there I way to get images display in a certain column to change periodically (variety is the spice of life!) and still display instantly each time?

Finally, I'd like to point out that this thread is closely related and, unfortunately, the problem discussed in it seems not to have been resolved:

https://www.googlecloudcommunity.com/gc/Feature-Ideas/Finer-grain-control-over-local-image-caching/i...

[Kirk_Masden]

I think I may have found the answer to my own question, which was: Is it my use of Concatenate() that is causing the problem (failure to load for offline use)?

The answer is "no."

Note that offline content viewing of images and documents only works when the links to the images or documents use relative paths as described in Work with PDF files.

https://support.google.com/appsheet/answer/10107724?hl=en

I'll report back when I confirm that placing the files in the same folder as the Google spreadsheet has fixed the issue.

[Kirk_Masden]

I have figured out today that the documentation I quoted above is wrong.  Once again, that documentation is as follows:

Note that offline content viewing of images and documents only works when the links to the images or documents use relative paths as described in Work with PDF files.

https://support.google.com/appsheet/answer/10107724?hl=en

However, I confirmed today that images with direct URLs (that is, beginning with http) are cached for offline views too.  Sigh 😞   I'll let AppSheet know that their documentation is wrong.

Too bad, too.  It was hoping to reduce the number of images that had to be loaded by using more direct URLs. 😞

[Steve]

AppSheet can't know what the generated URL will be until it's generated, so there's no way to preemptively fetch the images. And, because the URLs aren't fixed, I would not be surprised if the images loaded with dynamic URLs are not cached.

[Kirk_Masden]

Thanks!  I think you're right.  I'm working on other ways around this -- to get the images cashed and also have them cached.  I'll report back later when I can finish testing everything.  One issue I'm facing is the that automated gifs I put in my app seem to interfere with the caching process.  I'm currently going through support to try to get this resolved.

For those who are interested, I've writing about the use of animated gifs here:

https://www.googlecloudcommunity.com/gc/Tips-Tricks/Animated-gifs/m-p/255103

https://www.googlecloudcommunity.com/gc/Tips-Tricks/Demonstrate-how-to-use-your-app-with-gifs/m-p/39...