Question

我想绑定到ArrayProxy的属性，以获取作为该Array成员的Object的计算属性。我在这里设置了一个JS小提琴：http://jsfiddle.net/sohara/MZeUu/31/

正如您在下面的代码中看到的，我的计算属性取决于thingsController中的聚合计算属性。但是，如果单击删除按钮，则不会再次调用percentWeight计算机属性，因为我不知道如何将此函数绑定到thingsController中的totalWeight计算属性。我确定有办法做到这一点.....任何想法？

window.App = Ember.Application.create();

App.Thing = Ember.Object.extend({
    weight: null,

    percentWeight: function() {
        return (this.get('weight') / App.thingsController.get('totalWeight')) * 100;
    }.property('weight')
    // This below doesn't work - can't access this property error
    //}.property('weight', 'App.thingsController.totalWeight')
});

App.thingsController = Ember.ArrayProxy.create({
    content: [
        App.Thing.create({weight: 100}),
        App.Thing.create({weight: 200}),
        App.Thing.create({weight: 300}),
        App.Thing.create({weight: 400})
        ],

    totalWeight: function() {
        var totalWeight = 0;
        this.get('content').forEach(function(item) {
            totalWeight += item.get('weight');
        });
        return totalWeight;
    }.property('@each.weight'),

    destroy: function(item) {
        this.removeObject(item);
    }

});

App.ThingView = Ember.View.extend({
    deleteButton: Ember.Button.extend({
        click: function(event) {
            var item = this.get('content');
            App.thingsController.destroy(item);
        }
    })
});

Answer 1

您遗失的一个绑定=＆gt; totalWeightBinding和一些代码重组，以便App.Thing知道App.thingsController。

<script type="text/javascript">
App.thingsController = Ember.ArrayProxy.create({
    totalWeight: function() {
        var totalWeight = 0;
        this.get('content').forEach(function(item) {
            totalWeight += item.get('weight');
        });
        return totalWeight;
    }.property('@each.weight'),

    destroy: function(item) {
        this.removeObject(item);
    }
});

App.Thing = Ember.Object.extend({
    weight: null,
    totalWeightBinding: 'App.thingsController.totalWeight',
    percentWeight: function() {
        return (this.get('weight') / this.get('totalWeight')) * 100;
    }.property('weight')
});
var things = [
  App.Thing.create({weight: 100}),
  App.Thing.create({weight: 200}),
  App.Thing.create({weight: 300}),
  App.Thing.create({weight: 400})
]
App.thingsController.set('content', things);

</script>

如何绑定到计算属性的不同对象中的属性

1 个答案: