I tried the below code that does not work. Also i searched via google but find nothing. Backbone's official documentation does not have an entry about loadUrl.
app_router.on('route:page', function(id, name) {
...
});
app_router.on('route:file', function(id, name) {
// first open the page
Backbone.history.loadUrl("page", function() {
// and open the file manager after page is loaded
});
});