Refreshing a template when controller property is changed ember

I want to refresh my template when one of its controller properties is changed via the click method of another controller (the property change is working). Right now, the selectedConvId value is null on page load, but it changes when a click is triggered on a certain conversation (I won't post the code for that). How can I refresh the template?

Rendering of the template inside the application template:

<div class="column-center-conversation">
    {{#if selectedConvId }}
        {{render 'convcenter'}}
    {{/if}}
</div>

Controller :

App.ConvcenterController = Ember.Controller.extend({

    selectedConvId: null,

    actions: {

        showSelectedConv: function(convid)
        {
            this.set('selectedConvId', convid);
            var conv = this.get('selectedConvId');

            ** This is where I want to refresh the template **
        }

    }

});