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Your LimeSurvey version: [6.1.8]
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I am creating a survey in LimeSurvey and I need my participants to click on a link:  www.koordinaten-umrechner.de  which will direct them to another webpage. There they should input their address and the webpage outputs the coordinates (longitude and latitude). Then they should click on the 'back' button in the browser to input this information about coordinates in the LimeSurvey. However, once they click the 'back' button there is an error message that the page doesn't exist: Confirm Form ResubmissionThis webpage requires data that you entered earlier in order to be properly displayed. You can send this data again, but by doing so you will repeat any action this page previously performed.

• Press the reload button to resubmit the data needed to load the page.

ERR_CACHE_MISS

So I wanted to ask if it is possible to go back to the survey after going to an external page?
I saw that users were raising an issue about switching to another survey and combining the data with the same ID, but I would just need participants to click on this link and immediately to come back to the survey. This is the main question in the survey, so any input is highly appreciated!

In the old days you would have embedded that website via an IFRAME into your survey. But that becomes harder cause that can be a security issue as well.

Since you have no control over the other website you can create a link which opens in a new tab/page.

<a target="_blank" href="https://deineseite">Text vom Link

And inform the people to close that page after they copied the coordinates. After closing the tab/page they will be on the same survey page and can continue.

Wouldn't the built in question type "map' give you the coordinates? I don't use this question type, but I thought it would.

manual.limesurvey.org/Question_type_-_Sh...cation_mapservice.29

I also got the coordinates by collecting GPS-Data via Javascript and it worked quite well. People must allow GPS though, when asked by the browser or smartphone.

Hi,
I really don't know why you try this approach.
As I understand you only need longitude and latitude, but none of the other provided coordinate types.
And let the respondent write down their coords and afterwards enter them into LimeSurvey is really cumbersome.
You see, the page does not return any values.

So, you should consider other approaches.
If you insists in using "koordinaten-umrechner", well, they offer an API

Other options:
Google Maps API
Here some explanation:
[url] www.thomatechnik.de/webmaster-tools/maps...ressen-bestimmen.htm [/url]

@holch already mentioned the GPS approach. Examples in the forum
E.g. this
[url] forums.limesurvey.org/index.php/forum/ca...ils-to-zoom-onto-map [/url]
[url] forums.limesurvey.org/index.php/forum/ca...oom-to-that-location [/url]
 

If you want to avoid the GPS allowance you may use the IP address to show a map 
Example you find in my "Tutorial 3: Gimmicks", Chapter 17. About page 10 in the German part.
Less exact than the GPS solution, but without the question to allow.
And the respondent may refine the locatioon.

Si there are many ways

JOffm

Thank you so much, this worked!

Thank you for your answer! I tried the map option, but it gives me coordinates only for cities, not for specific addresses.

Thank you for the answer! We can really use Google Maps because of data protection issues, and allowing GPS wouldn't solve this concrete problem, because participants need to enter coordinates of several addresses- where they live, where they work etc. so it is not related to where they are at the moment.

*We can't really use Google Maps...

Na, und? Dann eben OSM.

What you did not explain yet - what do you need the coordinates for?
Do you want to calculate distances, or what?

If you do not need to store the coordinates for some later calculations in LimeSurvey, just let the respondent enter the addresses (what you want them to do).
Later in your analyzis you can use "koordinaten-umrechner" to convert the whole list of addresses. ("listconvert").

In case you want to store the coordinates:
Show several OSM maps.
You may use the IP address to show a map section with a resolution that very probably covers the home address, the working address, etc.
Here the respondent can mark the correct location.
That's the easy solution.

Or use the API! Contact them

Ja, wir bieten auch eine API für den Koordinaten-Umrechner an. Schreiben Sie uns bei Interesse gerne eine E-Mail an hello@coordinates-converter.com.

To be honest: I'd NEVER enter my correct home address in a survey (always something else in a radius of about 1km). 

Joffm

We need coordinates to extract environmental features, such as greenery etc. Thank you!

Well, and why don't you use a simple IFrame?
 

Joffm