Ember js: How to retrieve the underlying model from a controller - javascript

I am trying to retrieve the underlying model object from a controller so that it can be persisted (I am not using ember-data). The obvious way would simply be:
controller.get('content');
But this doesn't work. The problem can be summed up as follows:
controller.set("content", model);
sets the content as expected and at this point
controller.get('content');
works as expected. But if I then decorate the controller with other properties eg.
controller.set('IamNotPartOfTheModel', false);
then suddenly the 'content' includes this new property. I would've expected the content to remain unchanged and the new property to only be applied to the controller itself. I understand the controller is a proxy for the model so for the most part they are treated as one and the same but surely they should still be separable when needed? The whole point of this pattern is to separate data that should be stored from data that is just temporary. Am I missing something?

To have your display specific properties out of the model, just specify them explicitly in the controller... Otherwise the controller acts as a proxy for its model... just have the property "iamNotPartOfTheModel" in your controller
App.IndexController = Ember.ObjectController.extend({
iamNotPartOfTheModel: null
})
Sample fiddle here

Your controller needs to interface to some kind of model. You can't separate the persisted model from the controller except by some kind of object reference. Even if you don't use ember-data, you'll still need to create objects which then plug into the content of the controller. Have a look at Evil Trout's blog for an implementation of ember without ember-data. Its a great starting point.

Related

Passing object available in the template into the {{render}} helper doesn't seem to work

I have an object defined globally as App.configObj which contains a property data. Inside a view's template I can use {{App.configObj.data}} to display the value and it works fine.
Inside that same template, I use {{render "viewC" model config=App.configObj}} to render a similar view, but the config property on that view remains null on didInsertElement. Other arguments set to primitive values are correctly set at that point.
Since App.configObj is definitely available in that context, shouldn't I be able to pass it into that view?
Here is the jsbin that illustrates the situation: http://emberjs.jsbin.com/misiyaki/12/edit
If you comment out the render call for ViewC, you can see that {{App.configObj.data}} renders just fine in the template.
My goal is to use an object encapsulating several properties to configure the view, so I need to be able to pass that object in. I spent a lot of time searching for similar content online but didn't find anyone trying this.
What am I missing?
Thanks!
I understand your struggle here with not being able to pass in a property in your render code... but in this case it doesn't seem that that is truly necessary.
Here is a fiddle with some changes to show you another way, that is essentially the same thing if i understood your intentions correctly. http://emberjs.jsbin.com/misiyaki/15/edit
The new code for your view:
App.ViewCView = Em.View.extend({
name: 'testName',
config: function () {
return App.configObj;
}.property(),
data: function () {
return this.get('config.data')
}.property('config'),
templateName: 'view-c'
});
Hope this helps!

Ember.js: Relationship between view input and model

I'm brand new to Ember.js, but well-versed in MVC and Backbone (even cocoa and smalltalk), but for some reason, Ember's insistence on its highly-obscured and inconsistent API is shielding me from understanding 1) binding and 2) how that relates to persisting records.
I have a view that has an input. I know that. I have a model that belongs to a controller. I know that. I don't understand how the view knows (or is supposed to know) about the controller, and I don't understand how the model gets the text I type into the view when I'm ready to push it to the backend (ostensibly with .save()). These are supposed to be boilerplate style things that Ember breathlessly abstracts away, but I find I'm having to go through the Ember.js source just to understand what the heck is happening.
I've read the docs, and their examples are so contrived as to be unusable (featuring only the most basic examples, which is pointless when we're talking about "ambitious web apps", which ember purports to be for).
It should be noted that we are using ember-data in house, and this particular route has multiple views, controllers and models.
So let's say you have an input in the index template:
<script type="text/x-handlebars">
{{input type="text" value=name}}
</script>
Ember automatically binds the App.IndexController to this template and the name property of the controller to the value property of the input field. As the value is changed in the input, it'll automatically update in the controller. When you're ready to save it in the model you can access the property in a action.
App.IndexController = Ember.ObjectController.extend({
actions: {
save:function() {
var name = this.get('name');
var model = this.store.createRecord('item');
item.set('name',name);
item.save();
}
}
});
This will trigger a post request to /items to store the item.
If you have a more specific example in mind, I can try to show you how that works.

angular js Service/Factory attributes behavior

I have a question about AngularJS behavior (JS behavior in general)
I have an Angular factory injected into a controller.
Here's a snippet of the controller code
$scope.localObjCollection= myObjFactorySvc.getObjCollection();
Let's assume that myObjFactorySvc.getObjCollection() returns the following object
[{"id":1"name":null,"address":null,"email":null},
{"id":2"name":null,"address":null,"email":null},
{"id":3"name":null,"address":null,"email":null},
{"id":4"name":null,"address":null,"email":null},
]
So, I'm pretty much using the factory to get the collection and storing it in $scope.localObjCollection.
My question is does $scope.localObjCollection have the value (copy) of the data returned by getObjCollection() or just a reference.
So if somewhere down in the controller source code, if I do
$scope.localObjCollection.push(newObj), does it also update the original collection in the Factory? It should I guess but I would like to understand the correct behavior
An array in JavaScript is an object and objects in JS are always passed/assigned by reference. Therefore your code would also update the original collection in the Factory, assuming that your myObjFactorySvc.getObjCollection() is something like this:
myObjFactorySvc.getObjCollection = function() { return someArrayVariable; }

Ember: transition to route passing the ID instead of obj

I have some route like /ads/:ad_id and from my controller I can do
this.transitionToRoute('ads.ad', adObj)
How can I do the similar thing but this time passing the ID instead of the loaded object?
O course I understand that I can load an obj by ID first, but Ember's power is in doing lost of boilerplate for us.
Update: So, as by default Ember serializes the model to URL params by doing like
mode_instance -> { model_name_id: model_instance.id }
My trivial attempt was doing
this.transitionToRoute('ads.ad', { id: adObjId })
But when passed a model object Ember does not re-fetch it.
So, the question: I have a route (single ad view) that depends on ad ID. I have this ID as number. I want to transition to this route like if I simply entered the url /ads/ID
This can be accomplish by passing the URL to transitionTo. For example,
this.transitionToRoute('/ads/' + adObjId)
The model() method will be called with the params from the URL.
Here is a use case for this:
Transitioning from a list view to a detail view. In the list view, the records don't have any relations tied to them, but the detailed view should side-load relational data. For this reason, the models are not 1:1 between the list view and detailed view. There should be a way to transition simply using the id.
Cp
What's your use case for this? Most cases when you would want to specify an object by id, you already have the object to pass to transitionTo. Can you provide more context about what you're trying to do? I think you can probably accomplish it without using the object id.
In any case, I don't think there's a good way to do this, because when you transition via transitionTo(someRoute, someModel), the route's model hook is not called, and the model you pass in (someModel) is supplied directly to the other route hooks (setupController(controller, model), redirect(model), renderTemplate(controller, model)).
See Ember.JS Route api -- model method for more details.

Backbone state handling with nested models?

I'd like to manage all hash state attributes (#) in one Backbone model.
StateModel //Pseudo
attributes
layout : string
modelType1 : model
modelType2 : model
This way I could consistently update history entries just by serializing this single model.
HistoryController
StateModel.bind("change", this.updateHistory);
[...]
state = StateModel.toJSON()
[...]
appRouter.navigate('v1' + state, false);
How do I make the HistoryController trigger change when the nested models (in the StateController) change?
And if the hash changes - and I'd like to update my StateModel - how do these changes propagate down to the nested models? (without causing a feedback loop)
Nested models in Backbone can be tricky because the getter and setter methods do not have built-in functionality to operate at depth. However, I have found that the best way to handle this is to store Backbone models inside other Backbone models. In your example, you would instantiate StateModel and then set its modelType1 and 2 to be, say, TypeModel instances. You can then stateModel.get("modelType1").bind("change",this.updateHistory) and stateModel.get("modelType2").bind("change",this.updateHistory). Alternatively, if you are going to be creating a lot of TypeModels, you can put this binding in the initializer function.
Secondly, you can stateModel.get("modelType1").bind("change",stateModelInstance.updateFoo) or whatever method you would like to call when the modelType model changes.
The nice thing about this pattern is that if you need stateModel to change one of the modelType models you can do stateModel.set({modelType1:newModel3}) or something of that ilk. If you have set the binding action in the ininitializer of TypeModel, everything will stay synced up. If you don't want to blow out the nested model on a change, just do stateModel.get("nestedModel1").set({"foo"}:"bar"). This shouldn't cause a feedback loop unless you have bound something to your stateModel change action that changes the nested Model again but I don't know why you would do that.

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