contextValue

Context value of the tree item. This can be used to contribute item specific actions in the tree. For example, a tree item is given a context value as folder. When contributing actions to view/item/context using menus extension point, you can specify context value for key viewItem in when expression like viewItem == folder.

"contributes": {
  "menus": {
    "view/item/context": [
      {
        "command": "extension.deleteFolder",
        "when": "viewItem == folder"
      }
    ]
  }
}

This will show action extension.deleteFolder only for items with contextValue is folder.

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