knolleary / BangleApps

Bangle.js App Loader (and Apps)

Bangle.js App Loader (and Apps)

Try it live at banglejs.com/apps

How does it work?

• A list of apps is in apps.json
• Each element references an app in apps/ which is uploaded
• When it starts, BangleAppLoader checks the JSON and compares it with the files it sees in the watch's storage.
• To upload an app, BangleAppLoader checks the files that are listed in apps.json, loads them, and sends them over Web Bluetooth.

What filenames are used

Filenames in storage are limited to 8 characters. To easily distinguish between file types, we use the following:

• +stuff is JSON for an app
• *stuff is an image
• -stuff is JS code
• =stuff is JS code for stuff that is run at boot time - eg. handling settings or creating widgets on the clock screen

Developing your own app

• Start writing your code in the IDE, with Save on Send in settings set to the default of To RAM
• When you have your app as you want it, add it as a file in apps/, lets assume apps/my-great-app.js
• Come up with a unique 7 character name, we'll assume 7chname
• Create apps/my-great-app.png as a 48px icon
• Use http://www.espruino.com/Image+Converter to create as 1 bit, 4 bit or 8 bit Web Palette "Image String" and save it as apps/my-great-app-icon.js
• Create an entry in apps/my-great-app.json as follows:

{
  "name":"Short Name",
  "icon":"*7chname",
  "src":"-7chname"
}

• Create an entry in apps.json as follows:

{ "id": "7chname",
  "name": "My app's human readable name",
  "icon": "my-great-app.png",
  "description": "A detailed description of my great app",
  "tags": "",
  "storage": [
    {"name":"+7chname","url":"my-great-app.json"},
    {"name":"-7chname","url":"my-great-app.js"},
    {"name":"*7chname","url":"my-great-app-icon.js","evaluate":true}
  ],
},

apps.json format

{ "id": "appid",              // 7 character app id
  "name": "Readable name",    // readable name
  "icon": "icon.png",         // icon in apps/
  "description": "...",       // long description
  "type":"...",               // optional(if app) - 'app' or 'widget'
  "tags": "",                 // comma separated tag list for searching

  "custom": "custom.html",    // if supplied, apps/custom.html is loaded in an
                              // iframe, and it must post back an 'app' structure
                              // like this one with 'storage','name' and 'id' set up

  "storage": [                // list of files to add to storage
    {"name":"-appid",         // filename to use in storage
     "url":"",                // URL of file to load (currently relative to apps/)
     "content":"..."          // if supplied, this content is loaded directly
     "evaluate":true          // if supplied, data isn't quoted into a String before upload
                              // (eg it's evaluated as JS)
    },
  "sortorder" : 0,            // optional - choose where in the list this goes.
                              // this should only really be used to put system
                              // stuff at the top
  ]
}

Credits

The majority of icons used for these apps are from Icons8 - we have a commercial license but icons are also free for Open Source projects.