iggrid on AngularJS view: How to call a controller function from a column template with button / onclick

I am developing an AngularJS app using iggrid with declarative options. The grid is bound to a datasource and is showing the data. So far it's working fine.

Now I added a column using a column template inluding a button group for executing several actions on each row. Here is the column definition:

<column key="actions" header-text="Aktionen" data-type="string" template="{{getHtml('#colTemplate')}}"></column>

An this is the column template (for simplicity I show just one button):

<script id="colTemplate" type="text/template" ng-non-bindable>
    <div class="btn-group btn-group-xs">
        <button type="button" class="btn btn-default"><i class="fa fa-edit fa-fw" onclick="viewDetails(${id})"></i></button>
    </div>
</script>

As you can see, I try to call the function viewDetails() of the views controller. This function looks like this:

function viewDetails(id) {
    common.$location.path('/portale/detail/' + id);
}

Other functions resp. action handlers like this need to work and manipulate the grids datasource.

Clicking on the button is throwing the following error on the javascript console:

Uncaught ReferenceError: viewDetails is not defined

How can I call the controller function?

Any help would be appreciated.