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CC2 Device Documentation

DataView JSON Format

A DataView is a single JSON object stored as a .json file in /dvs/ on the device (or embedded inline in allocdata). This page documents the complete JSON structure.

Top-level structure

Section titled “Top-level structure”
{
  "displayName": "My Application",
  "displayIcon": "my_app_icon",
  "target_size": {
    "w": 176,
    "h": 264,
  },
  "infopages": [
    {
      "id": "1",
      "infowidgets": [],
    },
  ],
  "dicts": [
    {
      "lang": "en",
      "description": "English",
      "dict": {
        "key": "value",
      },
    },
  ],
}

Top-level attributes

Section titled “Top-level attributes”
Attribute Type Required Description
displayName string yes User-visible name shown on the home screen and in the system bar
displayIcon string no Preloaded icon name or base64 PBM data used as the app icon on the home screen
target_size object no The screen size this DataView was designed for. Contains "w" and "h" in pixels. Default: { "w": 176, "h": 264 }
infopages array yes Array of 0–N InfoPage objects (see InfoPage)
dicts array no Array of language dictionaries for multi-language support (see Multi-language)

Naming rules

Section titled “Naming rules”

allocdata integration

Section titled “allocdata integration”

DataViews are referenced from allocdata.json (or unallocdata.json) under the data.user.apps section:

{
 "data": {
 "global": {
 "dev": {
 "<device-name>": { "<config-attributes>" }
 }
 },
 "network": {
 "networks": {
 "<name>": { "<network-config>" }
 },
 "networkOrder": [ "<name>" ]
 },
 "user": {
 "visitor": "<optional-user-name>",
 "apps": {
 "<dv-source-ref>": {
 "id": "<dv-name-when-loaded>",
 "src": "local | inline | remote",
 "data": {
 "<widget-name>": "<initial-value>"
 }
 }
 }
 },
 "apps": {
 "<dv-name>": { /* DataView JSON goes here if src:inline */ }
 },
 "dicts": [
 "config/names.json",
 "config/locations.json"
 ]
 }
}

Source types

Section titled “Source types”
src value Meaning
"local" Load DataView from /dvs/<dv-source-ref>.json on the device flash
"inline" DataView JSON is embedded in the data.apps section of allocdata
"remote" DataView is fetched from a remote URL (advanced use)

Pre-initializing widget values

Section titled “Pre-initializing widget values”

The data object inside each app entry allows you to set the initial values for named widgets at allocation time, before any MQTT downlink messages are sent:

{
  "apps": {
    "duresshome": {
      "src": "local",
      "data": {
        "user_name": "Jane Smith",
        "user_id": "EMP-4421",
        "department": "A&E",
      },
    },
  },
}

These values are loaded once when the device enters the allocated state.

Complete annotated example

Section titled “Complete annotated example”
{
  "displayName": "Patient Tracker",
  "displayIcon": "hospital_icon",
  "target_size": {
    "w": 176,
    "h": 264,
  },
  "infopages": [
    {
      "id": "1",
      "infowidgets": [
        {
          "name": "patient_name",
          "interaction": "dynamic",
          "region": {
            "x": 0,
            "y": 0,
            "w": 176,
            "h": 40,
          },
          "format": "text",
          "formatter": {
            "name": "string",
            "font": {
              "weight": "Bold",
              "sz": 14,
            },
            "halign": "center",
            "autobreak": true,
          },
          "value": "Loading...",
        },
        {
          "name": "ward_label",
          "interaction": "static",
          "region": {
            "x": 0,
            "y": 45,
            "w": 80,
            "h": 20,
          },
          "format": "text",
          "formatter": {
            "name": "string",
            "sz": 10,
          },
          "value": "Ward:",
        },
        {
          "name": "ward_value",
          "interaction": "dynamic",
          "region": {
            "x": 80,
            "y": 45,
            "w": 96,
            "h": 20,
          },
          "format": "text",
          "formatter": {
            "name": "string",
            "sz": 10,
          },
          "value": "",
        },
        {
          "name": "alert_btn",
          "interaction": "button",
          "region": {
            "x": 20,
            "y": 200,
            "w": 136,
            "h": 40,
          },
          "format": "text",
          "formatter": {
            "name": "string",
            "halign": "center",
            "outline": "solid_rounded",
            "outline_sz": 2,
          },
          "value": "Send Alert",
          "actions": [
            {
              "a": "updateRemote",
              "p": "app.tracker.alert_btn:pressed",
            },
            {
              "a": "beep",
              "p": "AT1",
            },
          ],
        },
      ],
    },
  ],
  "dicts": [
    {
      "lang": "en",
      "description": "English",
      "dict": {
        "tracker-ward": "Ward:",
      },
    },
    {
      "lang": "fr",
      "description": "Fran\u00e7ais",
      "dict": {
        "tracker-ward": "Service:",
      },
    },
  ],
}
Section titled “Related”