Q:

Meteor JS cannot sort data

I have a button in the body that when clicked, should sort descending.  When I do, nothing happens.  I believe my code is correct, but perhaps I'm missing something?
Here's the js:
Tasks = new Mongo.Collection("tasks");

Template.body.events({
"click .sort_title": function () {
return Tasks.find({}, {sort: {movie_title: -1}});
console.log('Sorting has been clicked');
}
});

And here's the HTML:
<table class="item_db">
<tr>
<th>Title <i class="fa fa-sort sort_title"></i></th>
</tr>
</table>

clicking the button doesn't even pass to the console log command, so it breaks at the task.

A:

The issue is the helper which is responsible for returning the tasks to display isn't receiving the sort toggle. By setting a Session value in the click event it will force the task helper, which is using the same Session key, to run again. See below for an example, as well as Meteor's documentation on reactivity.
Tasks = new Mongo.Collection("tasks");

Template.body.events({
  "click .sort_title": function () {
    var sortValue = Session.get('sort') || 1;
    Session.set('sort', sortValue * -1);
  }
});

Template.body.helpers({ 
  tasks: function () {
    var sortValue = Session.get('sort') || 1;
    return Tasks.find({}, {sort: {movie_title: sortValue}}); 
  }
});

