Hi Viktor

It is not possible to set prevalues for the radiobuttonlist prevalue editor. It is only used for Grid Layouts atm. I have logged a feature request on the issue tracker to make it usable from package.manifest.

In the mean time I think the best option would be to make a custom prevalue editor. Something like this:

1: Create a folder in /App_Plugins/ call it radiobuttonprevalue

2: Create three files in /App_Plugins/radiobuttonprevalue/, package.manifest, radiobuttonprevalue.controller.js and radiobuttonprevalue.html.

3: In package.manifest all we have to do is make sure the controller is added to Umbraco so:

{
    javascript: ["~/app_plugins/radiobuttonprevalue/radiobuttonprevalue.controller.js"]
}

4: In radiobuttonprevalue.controller.js you set the prevalues you want:

app.controller("my.radiobuttonprevaluecontroller", function ($scope) {

    $scope.model.prevalues = [
        "option 1",
        "option 2",
        "option 3"
    ];

});

5: You can use the view from the radiobuttonlist.html, all you need to add is the controller, so radiobuttonprevalue.html would look like:

<ul class="unstyled" ng-controller="my.radiobuttonprevaluecontroller">
    <li ng-repeat="preval in model.prevalues">
        <label class="checkbox">
            <input type="radio" ng-model="model.value" value="{{preval}}" /> {{preval}}
        </label>
    </li>
</ul>

And that's it. Prevalue editor done!

To use it simply add it to your custom editors package.manifestfile:

prevalues: {
    fields: [
        {
            label: "Options",
            description: "Some options to choose from",
            key: "options",
            view: "~/app_plugins/radiobuttonprevalue/radiobuttonprevalue.html",
        }
    ]
}

and now you get a radiobuttonlist with 3 options :)

The value selected will be available on the property editor in $scope.model.config.options.

Hope this helps

/rune