topic Re: ArcGIS SDK > 4.15 MapView is not a constructor in ArcGIS JavaScript Maps SDK Questions

ArcGIS SDK > 4.15 MapView is not a constructor

GavinBoyd — Thu, 22 Jun 2023 21:58:39 GMT

The below code works when launched when created as an html page in notepad. However, once I try to deploy as part of a Asp.net Core project it will not display unless i change the Arcgis SDK down to 4.15. Anything greater than SDK 4.16 will not work. Can't find any reason for this on the web. Below code returns error: Uncaught TypeError: MapView is not a constructor.

```
<link rel="stylesheet" href="https://js.arcgis.com/4.27/esri/themes/light/main.css" />
<script src="https://js.arcgis.com/4.27/"></script>

const view = new MapView({
container: "viewDiv",
map: webmap
});

view.when(() => {
const editor = new Editor({
view: view
});

// Add the widget to the view
view.ui.add(editor, "top-right");
});
});

</script>

```

Re: ArcGIS SDK > 4.15 MapView is not a constructor

JoelBennett — Thu, 22 Jun 2023 22:35:08 GMT

You may be able to resolve this conflict by moving your two script tags to the bottom of the document (e.g. just before the closing tag for the body).

Re: ArcGIS SDK > 4.15 MapView is not a constructor

GavinBoyd — Fri, 23 Jun 2023 01:14:47 GMT

Thanks for the comment @JoelBennett . By moving <script src="https://js.arcgis.com/4.27/"></script> just above the div it eliminates the constructor error but then I get the following error:

Uncaught ReferenceError: require is not defined

Re: ArcGIS SDK > 4.15 MapView is not a constructor

JoelBennett — Fri, 23 Jun 2023 01:03:11 GMT

It sounds like you may have reversed the order of your script tags, making what used to be first one now the second. However, the "shorter" script tag needs to come before the "longer" one. Basically, you'll have this:

And then you should try moving those two as low in the document as possible (preferably right before the </body> tag).

Re: ArcGIS SDK > 4.15 MapView is not a constructor

GavinBoyd — Fri, 23 Jun 2023 02:10:24 GMT

Yes, that was a silly error from me, thanks for clarifying. However, it hasn't fixed my problem, unfortunately. The key to my issue lies in how visual studio and or my Asp.Net Core Web App seems to deal with the different js.arcgis.com/4XX versions. The code above works fine with sdk 4.15 but the moment I try to upgrade it to 4.16 or higher it returns the 'not a constructor' error. It is as though visual studio or my app just can't read the sdk reference or the require tags. Any thoughts what might be causing this or a suggested workaround?

Re: ArcGIS SDK > 4.15 MapView is not a constructor

JoelBennett — Fri, 23 Jun 2023 21:24:11 GMT

Unfortunately, I don't think I'll be able to offer much else here. I remember a project a co-worker was working on had an issue resembling this one, and our solution at the time was to do what I described above. It seemed like some other components on the page had their own version of a "require" function which was causing the conflict, but that's about all I recall.

Re: ArcGIS SDK > 4.15 MapView is not a constructor

GavinBoyd — Sat, 24 Jun 2023 02:59:40 GMT

No problem. Thank you for trying to help, anyway. Cheers

Re: ArcGIS SDK > 4.15 MapView is not a constructor

GavinBoyd — Sun, 25 Jun 2023 00:06:17 GMT

Had a hunch that this had something to with my page/view references conflicting js. By doing the following sdk 4.27 is no working.

The way I got around was to comment out this section of the shared Asp.net Core App _layout.cshtml view

As it appears to conflict with any arcgis sdk of higher than 4.15

Re: ArcGIS SDK > 4.15 MapView is not a constructor

JDonoghue — Wed, 04 Oct 2023 20:49:32 GMT

I followed Gavin's advice above and got my map to render just fine. However, commenting out the jquery and bootstrap references in the_Layout page disabled the other bootstrap objects my app was using. For example, bootstrap tabs and collapse items no longer functioned. Any thoughts or advice? Thanks in advance.

Re: ArcGIS SDK > 4.15 MapView is not a constructor

Steve_ — Mon, 29 Jan 2024 06:01:43 GMT

I got the same error in an .NET8 ASP.NET Core MVC project and was able to fix it for ArcGIS JS 4.28 by ensuring the ArcGIS script was loaded after bootstrap.