Databases
StackOverflow2013
Postsdbo
POHow to make a computed property that depends on a global class attribute?
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POHow to make a computed property that depends on a global class attribute?
    primarykey
    data
    text
    <p>I wanna create a property that depends on a global attribute:</p> <pre><code>App.Test= Em.Object.extend(); App.Test.reopenClass({ all: Em.A() }); App.Other = Em.object.extend({ stuff: function() { return "calculated stuff from this.get('foo') and App.Test.all"; }.property('foo', 'App.Test.all.@each.bar') }); </code></pre> <p>As a workarround I could create a observer and always set a dummy property with a new random value to trigger the property change, but is there a better way to do this?</p> <p>I need this for some caching. I've a really crazy, and single threaded backend. So I write my own Model classes. So I try to reimplement a bit of the logic in the client for a better caching.</p> <p>Ive an Item class (App.Item) and another class where each instance has a calculated reduced list of Items.</p> <pre><code>App.Model = Em.Object.extend({ }); App.Model.reopenClass({ all: Em.A(), load: function(hash) { return this.get('all').pushObject(this.create(hash)); } }); App.Item = App.Model.extend({ }); App.List = App.Model.extend({ loadedInitItems: false, items: function() { if(!this.get('loadedInitItems')) { this.set('loadedInitItems', true); Backend.call('thelist', function(item) { App.Item.load(this); }); } return App.Item.all.filter(function(item) { // heavy filter stuff, depends on a lot of propertys on the current list instance }); }.property('someprops', 'App.Item.all.@each.foo') }); </code></pre> <p>Backend.call represents some AJAX stuff</p> <p>the point is, that now any item could change so that the filter will return something diffrent. And there are other places om the application, where the user can add Items. I dont want to call the backend again, because its very slow! And I know that the backend will not modify the list! So I wanna cache it.</p> <p>This is just a reduced example of my use case, but I think've described the point. In reallity I have this dozend of times, with over 25000 objects.</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USLux
    1. USLux
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. COcould you explain more in detail what your use case is, it looks like you are fighting the framework...
      singulars
      1. POHow to make a computed property that depends on a global class attribute?
      1. USintuitivepixel
    2. CO@intuitivepixel I've tried to explain it a bit. All about caching.
      singulars
      1. POHow to make a computed property that depends on a global class attribute?
      1. USLux
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload