Question

Below is a code that describes nested tree model, and a sample data in json.
How do I reset blocks with provided data?

var Block, Blocks, data, blocks;

Block = Backbone.Model.extend({
  initialize: function() {
    this.blocks = new Blocks;
  }
});

Blocks = Backbone.Collection.extend({
  model: Block
});

data = [
  {
    id: 1,
    blocks: [
      {id: 2, blocks: [{id: 3}]}, {id: 4}
    ]
  },
  {
    id: 5
  }
];

blocks = new Blocks;

Answer 1

var Block, Blocks, data, blocks;

Block = Backbone.Model.extend({
  initialize: function() {
    // access 'blocks' via attributes
    // and initialize collection by passing the attributes in
    this.attributes.blocks = new Blocks(this.attributes.blocks);
  }
});

Blocks = Backbone.Collection.extend({
  model: Block
});

data = [
  {
    id: 1,
    blocks: [
      { id: 2, 
        blocks: [
          { id: 3 }
        ]
      }, 
      { id: 4 }
    ]
  },
  {
    id: 5
  }
];

// initialize blocks by passing 'data' in
blocks = new Blocks(data);​

Ok, well, since attributes are stored under attributes prior to initialize, you need to call this.attributes.blocks in your initialize function to ensure there is no mix-up with this.blocks (which there was).

You also need to initialize blocks by passing data into it’s constructor, which is the same for every other instance of Blocks, i.e., those also stored inside each Block.