Get / Set entity when dealing with relation attribute - angularjs

Question

I'm working in a Wakanda environnement with the angular-wakanda connector.
Assume this model : Employee(firstName,lastName,company) and Company(name)
In the employee form, I have a select input that is filled with companies names (which is a entity collection).
I have set a ng-model="selectedCompany" in the select
When I select one company and perform a save, the value I get represent the value I have pass in the value of my option (ID or name).
When I assign the value to a new entity using the $create() method, I don't know which way to set the entity to the relation attribute. I assume that I have to give an entity. The thing is that I already have the entitycollection with all the entities. So I don't see the reason why should I query again the server just to assign somthing that I have already.
So the thing is that we should have a method like $find or $getById that will not do a request on the server but get the entity that is already loaded in the entityCollection. For now I use my own method that do a simple loop over my array. (I can share the code if anybody need it)
Am I missing a way to do that?

Answer 1

Assuming your selectedCompany variable contains an entity (of type Company), you only have to pass this variable on the $create() call with the property name like this:
var newEmployee = ds.Employee.$create({
firstName: 'foo',
lastName: 'bar',
company: $scope.selectedCompany
});
If selectedCompany contains only company name or ID, it's on you to have an array to map the companies with their name or ID. Something like that:
//When retrieving collection
var companyMap = [];
companies.forEach(function (company) {
companyMap[company.ID] = company;
}
//When you want your company with its ID
var company = companyMap[$scope.selectedCompany];
But the simplest way is the first, with your <select> directly iterating through entity collection, so that you can deal with entities.
Edit: Retrieving object with ng-option
To get the object on which you iterate on your select, you can use ng-option like this:
<select
ng-model="selectedCompany"
ng-change="companyChanged()"
ng-options="c.name for c in companies"
>
</select>
On the controller
$scope.selectedCompany = null;
$scope.companyChanged = function () {
if ($scope.selectedCompany) {
//selectedCompany is your company entity
//you can manipulate it like any other entity
$scope.selectedCompany.$save(); //for example
}
};

Answer 2

I think that your real problem is that you iterate on name/ID of each entity of company Collection.
This is the bad way to iterate on collections :
<select ng-model="selectedCompany" ng-options="company.nom as company.nom for i in collenctionOfCompanies">
<option value=""></option>
</select>
In this case selected company will contain only the name of the company.
But if you change your code as this :
<select ng-model="selectedCompany" ng-options="company as company.nom for i in collenctionOfCompanies">
<option value=""></option>
</select>
Then selectedCompany will contain the entity