{
  "surface_id": "surface-dropdown-selection",
  "surface_version": 1,
  "payload": {
    "objects": [
      {
        "dataModelUpdate": {
          "surfaceId": "surface-dropdown-selection",
          "contents": [
            {
              "key": "location",
              "valueArray": [
                {
                  "valueString": "Unknown"
                },
                {
                  "valueString": "Shanghai"
                }
              ]
            },
            {
              "key": "hasLocation",
              "valueBool": false
            }
          ]
        }
      },
      {
        "surfaceUpdate": {
          "surfaceId": "surface-dropdown-selection",
          "components": [
            {
              "id": "root",
              "component": {
                "DropdownSelection": {
                  "selection": {
                    "path": "/location"
                  },
                  "items": [
                    "Beijing",
                    "Shanghai"
                  ],
                  "hasSelection": {
                    "path": "/hasLocation",
                    "literalBoolean": false
                  },
                  "placeholder": {
                    "literalString": "Select location"
                  }
                }
              }
            }
          ]
        }
      },
      {
        "beginRendering": {
          "root": "root",
          "surfaceId": "surface-dropdown-selection"
        }
      }
    ]
  }
}