Survey123 limits zoom level on tpk when device is offline

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12-18-2018 10:23 AM
KeithOlsen
Occasional Contributor

I'm using Survey123 Connect 3.1.126 to publish a survey I would like to work when the field device is not connected to cell or wifi. I created a tile package with arcMap 10.6.1 (create map tile package) to level 16 and put said tpk file in the media directory of the survey. It downloads and works fine when my field device is on wifi, but when it's offline the zoom level is limited. I can only zoom in about half way. This behavior is the same on a Samsung galaxy tabPro 12.2 and also my Pixel 2 phone. The tpk file is on the device, so why would it matter if I'm online or not? It's clearly loading tiles off the device up to a certain point. What might be limiting it? Thanks.

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3 Replies
JamesTedrick
Esri Esteemed Contributor

Hi Keith,

By 'about half way', what zoom level do you see (if you can compare tiles with a web map or start from the world in)?  Survey123's behavior is to stop zooming once you reach the maximum tile present (in contrast to the JSAPI, which allows you to "overzoom" and see an enlarged version of the last tile level). This combined, with the high pixel density of phones, can leave the impression that you aren't as zoomed in as it appears.

KeithOlsen
Occasional Contributor

Hi James. When zoomed all the way out to the home position, I can zoom in 8x on my phone when it's offline and another 6x when it has a cellular or wifi connection. It's possible that the last 6x zooms are not loading more data but overzooming as you describe. Either way, there is a lot of information there that I'm missing when it doesn't zoom in past the first 8x. Is there any way to turn on the overzoom when my device is offline?

Another thing that is going on is I have a vector layer that is zoom-limited in the map that the tile package was created from and it happens to appear at exactly the zoom level (8x) where the device will no longer zoom in when offline. Maybe this is a coincidence?

I'll check this thread periodically. For some reason, GeoNet does not send me email when there is a response to this thread even though I have that setup in my profile. Thanks!

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JamesTedrick
Esri Esteemed Contributor

Hi Keith,

Thanks for the detail.  It does sound like this might possibly be related to 'overzoom'.  It also sounds like you are accessing a service with greater than L16 tiles - this would also cause the behavior that is described (some Esri baseman's have L19 and further support).