主干.bind('change'，_.bind(this.render，this))未注册

Question

我有一个measure模型，它由两个集合组成，一个是beats集合，另一个是measureRep资源集合。每个集合分别由beat模型和representation模型组成。

每当measureRep资源集更改时(通过添加或减去representation模型)，我希望使用render函数()重新呈现measureView (它拥有measure模型，因此还有measureRep资源集合)。

我通过以下函数在另一个视图中添加了一个新模型：

var representationModel = new RepresentationModel({representationType: newRepType});
StageCollection.get(cid).get('measures').models[0].get('measureRepresentations').add(representationModel);

我可以看到，在measure及其measureRep集合被正确添加之前和之后，measureView上的绑定调用没有注册更改并调用render函数。我甚至将绑定放在模型上，以表明后端正在更新，但是它没有响应。这使我相信，视图和模型是解耦的，但这是没有意义的，因为它最初是从模型中呈现的。以下是相关档案：

measureView.js视图

define([...], function(...){
  return Backbone.View.extend({

    initialize: function(options){
      if (options) {
        for (var key in options) {
          this[key] = options[key];
        }
        this.el = '#measure-container-'+options.parent.cid;
      }

      window.css = this.collectionOfRepresentations; //I use these to attach it to the window to verify that the are getting updated correctly
      window.csd = this.model;  // Same
      _.bindAll(this, 'render'); // I have optionally included this and it hasn't helped
      this.collectionOfRepresentations.bind('change', _.bind(this.render, this));

      this.render();
    },

    render: function(){
      // Make a template for the measure and append the MeasureTemplate
      var measureTemplateParameters = { ... };
      var compiledMeasureTemplate = _.template( MeasureTemplate, measureTemplateParameters );
      // If we are adding a rep, clear the current reps, then add the template
      $(this.el).html('');

      $(this.el).append( compiledMeasureTemplate )

      // for each rep in the measuresCollection
      _.each(this.collectionOfRepresentations.models, function(rep, repIndex) {
        var measureRepViewParamaters = { ... };
        new MeasureRepView(measureRepViewParamaters);
      }, this);

      return this;
    },
    ...
  });
});

measure.js模型

define([ ... ], function(_, Backbone, BeatsCollection, RepresentationsCollection) {
  var MeasureModel = Backbone.Model.extend({
    defaults: {
      beats: BeatsCollection,
      measureRepresentations: RepresentationsCollection
    },
    initialize: function(){
      var logg = function() { console.log('changed'); };
      this.measureRepresentations.bind('change', logg);
      this.bind('change', logg);
    }
  });
  return MeasureModel;
});

representations.js收藏

define([ ... ], function($, _, Backbone, RepresentationModel){
  var RepresentationsCollection = Backbone.Collection.extend({
    model: RepresentationModel,
    initialize: function(){
    }
  });

  return RepresentationsCollection;
});

我也尝试过在measure模型上注册绑定，而不是它的子集合，但两者都不起作用。

_.bindAll(this, 'render');
this.model.bind('change', _.bind(this.render, this));

Answer 1

请参阅：https://stackoverflow.com/a/8175141/1449799

为了检测模型添加到集合中的情况，您需要侦听添加事件(而不是变更事件，当集合中的模型更改http://documentcloud.github.io/backbone/#Events-catalog时，更改事件将触发)。

所以试着：

this.measureRepresentations.bind('add', logg);