fixtures.js

sc_require('models/project');

MyApp.Project.FIXTURES = [
  {
    guid:1,
    name: "Foo"
  },
  
  {
    guid:2,
    name:"Bar"
  }
];

main.js

MyApp.main = function main(){
  var projects = MyApp.store.find(MyApp.Project);
  MyApp.projectsController.set('content', projects);
}

MyApp.projectsController = SC.ArrayController.create({});

main_page.js

MyApp.mainPage = SC.Page.design({
// snip..
  mainPane: SC.MainPane.design({
    childViews: [SourceListView.design({
      contentValueKey: "name",
      contentBinding: "MyApp.sourcesController.arrangedObjects",
      selectionBinding: "MyApp.sourcesController.selection"
    })]
  })
// snip..
})

project.js

MyApp.Project = SC.Record.extend({
  name: SC.Record.attr(String)
})

sources.js

sc_require('controllers/projects.js')

MyApp.sourcesController = SC.TreeController.create({
  content: null,
  projects:'',
  projectsBinding: 'MyApp.projectsController.content',
  
  buildSources: function(){
    var p = this.get('projects'),
        projectsSource;
    if(!p) return;
    
    projectsSource = this.buildProjectsSource(p);
    console.log(projectsSource);
    var sources = SC.Object.create({
      treeItemIsExpanded: YES,
      treeItemChildren: [SC.Object.create({
        treeItemIsExpanded: YES,
        group: true,
        name: "Projects",
        treeItemChildren: projectsSource
      })]
    });
    this.set('content', sources);  // watch the console explode as this causes an inifnite loop.
  }.observes('projects'),
  
  buildProjectsSource: function(projects){
    var ret = [];
    for(var i = 0, len = projects.length(); i < len; i++)
      ret.push(SC.Object.create({
        name: projects.objectAt(i).get('name')
      }));
    return ret;
  }  
}) ;