无法从视图访问控制器的计算属性 [英] Trouble accessing controller's computed property from view

问题描述

我的控制器具有计算所得的属性:

My controller has a computed property:

App.IndexController = Ember.ArrayController.extend({

    grandTotal: function () {
        return this.getEach('total').reduce(function(accum, item) {
            return accum + item;
        }, 0);
    }.property('@each.total'),

});

但是我无法通过视图访问它.这是我的看法:

but I'm having trouble accessing it with my view. Here's my view:

App.SummaryView = Ember.View.extend({

    templateName: 'summary',

    companiesChanged: function() {
        Ember.run.once(this, 'logCompanies');
    }.observes('controller.@each'),

    logCompanies: function() {
        console.log(this.get('controller').get('model').get('length'));
        console.log(this.get('controller').get('grandTotal'));
    }

});

.get('length')正确返回，所以我知道何时调用该模型.但是 grandTotal 返回为 NaN ，尽管我知道它已正确编码，因为它已在模板中呈现.出于其他原因，我需要在我的视图内访问它.

.get('length') returns correctly, so I know when this is called the models are loaded. But grandTotal is coming back as NaN, even though I know it's coded correctly since it's being rendered in the template. I need to access it within my view for additional reasons.

有什么想法吗?

推荐答案

即使控制器的计算属性随@ each.total更改，该视图也仅关心控制器的属性.因此，该视图错误地观察了@each模型，而该模型本来应该观察 controller.grandTotal :

Even though the controller's computed property changes with @each.total, the view only cares about the controller's property. Thus, the view was wrongly observing @each model, when it should have just been observing controller.grandTotal:

App.SummaryView = Ember.View.extend({

    templateName: 'summary',

    companiesChanged: function() {
        Ember.run.once(this, 'logCompanies');
    }.observes('controller.grandTotal'),

    logCompanies: function() {
        console.log(this.get('controller').get('model').get('length'));
        console.log(this.get('controller').get('grandTotal'));
    }

});

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