Notes on Continuing Extension Development for Next Design V3.1

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Summary

If you plan to continue developing extensions for V3.1 without updating to V4.0, you need to change the settings of your extension development project. (No changes are required if you use pre-built extensions as they are.)

Target

You need to change the settings in either of the following cases.

• Creating projects using the following project templates:
  • Next Design Extension project template
  • Next Design Extension (Extension Points) project template
• Creating projects using NDExt commands

Symptom

Projects created using the method above are configured to use the latest version of the extension development package. With the V4.0 update, the latest version of the extension development package is also updated to the V4.0 package. Therefore, when building extensions for V3.1, you need to change your settings to use the V3.1-compatible version of the extension development package.

If you rebuild without changing the settings, it will automatically update to use the latest V4.0 package. If you install that extension and launch Next Design V3.1, the following error message will appear, and the extension will not work.

Failed to activate extension "xxxx". (Unable to load one or more of the requested types. Could not load file or assembly 'NextDesign.Desktop, Version=4.0.x.xxxxx, Culture=neutral, PublicKeyToken=null'. The system cannot find the file specified.)

Solution

To avoid the above error, please update the extension development project settings as follows.

Explicitly specify the version to use the V3.1-compatible version for the following packages used in the extension development project.

Target Package	V3.1-compatible version
NextDesign.Desktop	3.1.3.30714
NextDesign.Core	3.1.3.30714
NextDesign.Desktop.ExtensionPoints (*)	1.2.2.41030 (Planned for release)

(*) Not required if you are not using the ExtensionPoints library.

Please note that the target framework for the extension development project should remain .NET 6.0.

Procedure

Follow the steps below to change settings in Visual Studio.

1. Open the solution in Visual Studio.

2. Right-click the project in the Solution Explorer and select [Manage NuGet Packages] to open the NuGet Package Manager.

3. [Installed] Select the tab and uninstall the corresponding package above.

4. [Reference] Select the tab and search for the corresponding package.

5. Specify the V3.1-compatible version of the relevant package and install it.

   

6. Run the build and verify that it succeeds.

Supplementary Notes

EXTENSIONS WITH THE ABOVE CHANGES WILL WORK WITH BOTH V3.1 AND V4.0.

That is all.