Succinct example of Aggregation Binding?

Hello everyone, I'm new to the world of sap UI5 and I'm trying to find examples/code snippets to point me in the right direction for a data element I'm creating. Essentially I'm attempting to create a growing list that will hold basic text data the user inputs. I would like to utilize a JSON object to hold/append the inputs and display them in the growing list. In order to get comfortable with the basics of Aggregation Binding I'm attempting to follow the example here.

Here's what I have.

App.controller.js

onInit: function() {     var oCompanyList = this.getView().byId("companyList");     oCompanyList.bindAggregation("content", "/companies", this.createContent.bind(this));
},
createContent: function (sId, oContext) {     var oUIControl = null;     // Define the description     var sDescription  = oContext.getProperty("name") + " (" + oContext.getProperty("county") + ")";     oUIControl = new sap.m.ObjectListItem(sId, {          title      : sDescription});     return oUIControl;
}

Content.json

{  companies : [  {  name : "Acme Inc.",  city: "Belmont",  state: "NH",  county: "Belknap",  revenue : 123214125.34    },{  name : "Beam Hdg.",  city: "Hancock",  state: "NH",  county: "Belknap"  revenue : 3235235235.23    },{  name : "Carot Ltd.",  city: "Cheshire",  state: "NH",  county: "Sullivan",  revenue : "Not Disclosed"    }]
}

App.view.xml

<core:View xmlns:core="sap.ui.core"     xmlns:mvc="sap.ui.core.mvc"     xmlns="sap.m"    controllerName="aggregation-binding.webapp"     xmlns:html="http://www.w3.org/1999/xhtml">  <Page title="Title">       <content>            <List id="companyList" items="{/companies}" growing="true" >            </List>       </content>  </Page></core:View>

I'll leave out index.html since I'm sure the error does not stem from there. When I attempt to run this I receive the following error "Error: Missing template or factory function for aggregation items of Element sap.m.List#idwebapp1--companyList !"

I've attempted to troubleshoot it for a while now and I'm wondering if perhaps there is a easier way to get comfortable with these bindings or if there is something obvious I'm missing!

Thanks in advance!