You have to put some code in javascript.
You can look at the code of SunData Widget. I think create a renderview function that make a minimum of things will be suffisant.
[{
Name: "RoomBa Widget",
Author: "Dani",
Version: "2015-04-30",
GroupName: '',
IconImage: 'pages/control/widgets/weather/earthtools/images/AtYourChoice.png',
StatusText: '',
Description: '',
Initialized: false,
RenderView: function (cuid, module) {
var container = $(cuid);
var widget = container.find('[data-ui-field=widget]');
//
if (!this.Initialized) {
this.Initialized = true;
}
}
}]
I know that if the Widget.js file doesn't exist the widget disappear from the control group.
But I don't test
Cheers
Dani