子级骨干视图如何在不将整个“ this”作为父类传递的情况下访问其父视图的特定属性

Question

I have a backbone parent view

var ParentView = Backbone.View.extend({
  a : 'apple',
  b : 'boy',
  c : 'cat',
  changingA : function() {
     this.a = 'Ami'
   },
  createChild = function() {
      new ChildView({a : this.a});
   }
});

and a child view

var ChildView = Backbone.View.extend({
   intialize : function(args) {
     this.aa = args.a;
   },

   someOperation : function() {
      console.log(this.aa);  // this is not the current 'a' value of parent.
         //here i always get 'apple' even if i change the value of 'a' in parent
    }
});

How can i make sure this.aa in child always get the current available value in parent view.

what is the main reason behind that? I am passing 'reference' of 'a' to child view. So child view should always have the updated value from parent. But why this do not happens??

I also do not want to pass the whole 'this' parameter as parent to child

Answer 1

You have to create an object and share the reference between parent and child

var ParentView = Backbone.View.extend({
  obj: {
    a : 'apple',
    b : 'boy',
    c : 'cat'
  },
  changingA : function() {
     this.obj.a = 'Ami'
   },
  createChild = function() {
      new ChildView({obj : this.obj});
   }
});

var ChildView = Backbone.View.extend({
   intialize : function(args) {
     this.obj = args.obj;
   },

   someOperation : function() {
      console.log(this.obj.a);  // this is not the current 'a' value of parent.
         //here i always get 'Apple' even if i change the value of 'a' in parent
    }
});

But be careful, this object reference is also shared between instances of "ParentView", to bypass this problem, create the obj reference inside constructor.