AngularJS: dynamic ng-bind property

I am doing a directive using select2. In my screen I will have many select2 objects, so this is why I want to use a directive that I can reuse it many times.

This is the directive:

<div class='form-group'>
<p>{{title}}</p>
<ui-select ng-model="selectedItem" on-select="onChange($item);" theme="bootstrap">
    <ui-select-match placeholder="{{placeholder}}">
        {{selectedItem.state}}
    </ui-select-match>

    <ui-select-choices repeat="item in items | filter: $select.search">
        <span ng-bind="item.state"></span>
    </ui-select-choices>
</ui-select>

Then I can do this to pass the parameters in my index.html file:

<strainer-select
                    items="strainer.states"
                    selectedItem="strainer.selectedState"
                    handler="onStateChange"
                    title="Estados"
                    placeholder="Escolha um Estado"
                ></strainer-select>

My problem is: in select2 I need inform a property of my object to "bind" and be displayed in the view, like so:

{{selectedItem.state}}

But, of course, the property 'state' will not be available in all objects. If I have a "city" object it can be "cityName" or if I want display users it could be just "name" or "userName".

I want avoid to make a interceptor and modify all my data to replicate properties just to fit a generic "name" in the data. If my object is:

{
    state: "Sao Paulo",
    uf: "SP"
}

I do not want change it to:

 {
    state: "São Paulo",
    uf: "SP",
    name: "São Paulo" // replicated from "state" property
}

jus to use inside my directive.

So, I've tried pass the bind property name dynamically to the directive like this:

 <strainer-select
                    items="strainer.states"
                    selectedItem="strainer.selectedState"
                    handler="onStateChange"
                    title="Estados"
                    placeholder="Escolha um Estado"
                    bindName="state"
                ></strainer-select>

And use it in the directive like this:

<span ng-bind="item.{{bindName}}"></span> // didnt work
<span ng-bind="item[{{bindName}}]"></span> // didnt work
<span ng-bind="item['{{bindName}}']"></span> // didnt work

And the ui-select-match looks worst....

<ui-select-match placeholder="{{placeholder}}">
    {{selectedItem["{{bindName}}"]}} // didnt work
</ui-select-match>

but with no success.

Does anyone has a clue how I can dynamically change the property name used by ng-bind?

Thank you.

Try

<span ng-bind="item[bindName]"></span>

<ui-select-match placeholder="{{placeholder}}">
    {{selectedItem[bindName]}}
</ui-select-match>

Whilst in ng-bind you do not need to escape the use of variables you are writing raw code - hence why you need to quote and direct usages of strings.