Customize Simulink Context Menu Using Extension Points

Since R2026a

Simulink^® context menus are the menus that open when you right-click something in Simulink. You can customize a subset of these menus: the context menu of the Simulink model canvas and the context menus of model elements in the model canvas such as blocks, signal lines, and annotations.

This page provides an overview of the customization workflow. For examples, see RichMenu Extension. To customize Stateflow^® context menus, see Add Menu Items to Model Editor Menus.

Customize Context Menu Using Extension Point

The context menus of the Simulink model canvas and model elements in the canvas are made up of widgets such as menu items, push buttons, text fields and check boxes. Widgets that contain other widgets are called containers. You can add custom widgets to context-menu containers at predefined locations called extension points. To learn about your options, see Simulink Context Menu Architecture.

Convert Customizations Created Before R2026a to Extension Point Format

To add a custom widget, take these steps.

1. Create a folder named resources. In the folder, create a JSON-formatted file named extensions.json. You can create more than one extensions.json file, as long as they are in different resources folders.

2. In the file, add a set of JSON declarations that define your customizations. For information about how to write the declarations, see RichMenu Extension.

   Code formatting mistakes such as missing brackets or incorrect line indentation can prevent your customizations from rendering as expected. To avoid formatting mistakes, consider writing the declarations in an IDE (Integrated Development Environment) equipped to help you format code, for example, Visual Studio Code.

3. Enable your customizations. Add the parent folder of the resources folder to the MATLAB^® path using the addpath function. Alternatively, right-click the folder in the Files panel and select Add to Path > Selected Folder(s) and Subfolders. Then, reload the Simulink studio configuration using the slReloadStudioConfig function.

To convert context menu customizations that you created prior to R2026a to the extension points format, use the slConvertCustomContextMenus function. To troubleshoot the conversion, see Resolve Failure to Convert Context Menu Customization to Extension Point Format.

Remove Customizations

To remove customizations from the context menu, do one of these:

• Remove the parent folder of the resources folder from the MATLAB path and then refresh the customizations.

• Rename the extensions.json file to anything other than extensions.json and then refresh the customizations.

• Delete the extensions.json file and then refresh the customizations.

Disable Context Menu Actions

Disabling the actions of default Simulink context menu widgets requires a different approach than adding custom widgets. For information on how to do so, see Disable Simulink and Stateflow Toolstrip and Context Menu Actions. Hiding default Simulink context menu widgets is not supported, but you can specify when custom widgets are visible by specifying a value for the when property in the JSON declarations that define the customization. See RichMenu Extension for details.