ember.js - ember 数据计算属性不适用于嵌套关联

Question

我有一个简单的数据模型：

一条腿，有很多玩家，有很多回合：

App.Store = DS.Store.extend({
  revision: 11,
  adapter: 'DS.FixtureAdapter'
});

App.Leg = DS.Model.extend({
  players: DS.hasMany('App.Player'),
  turnCount: function() {
    var i = 0;
    this.get('players').forEach(function(p) {
      i+= p.get('turns.length');
    });
    return i;
  }.property('players.@each.turns.length')

});

App.Player = DS.Model.extend({
  leg: DS.belongsTo('App.Leg'),
  turns: DS.hasMany('App.Turn')
});


App.Turn = DS.Model.extend({
  player: DS.belongsTo('App.Player')
});

当我创建一个新的转弯时，计算的属性turnCount不会自动更新，但它应该，对吧？

/*
* do this on the console to verify
*/

var leg = App.Leg.createRecord();
var player = leg.get('players').createRecord();

leg.get('turnCount');
// => 0
player.get('turns').createRecord();
leg.get('turnCount')
// => 0

更新

似乎如果你坚持一层嵌套的东西就可以了。所以：

.property('players.@each.someProperty') 

只要 someProperty 不是可枚举的，就可以工作。

Answer 1

Try this:

.property('players.@each.turns.@each')

You could also use the reduce method to calculate totals:

turnCount: function() {
  return this.get('players').reduce(function(value, player) {
    return value + player.get('turns.length');
  }, 0);
}.property('players.@each.turns.@each')