Reuse Object Reference in a Template - angularjs

Question

I have a directive like this:
app.directive("myData", function() {
return {
restrict: "E",
templateUrl: "myTemplate.html"
};
});
Then in myTemplate.html I have something like:
<input type="number"
ng-if="(getMyObject(item.DataId)).Valid"
ng-model="(getMyObject(item.DataId)).Price"/>
<div ng-bind="(getMyObject(item.DataId)).Price"
ng-if="!(getMyObject(item.DataId).Valid"></div>
This directive is placed inside an ng-repeat (hence the item.).
My question is how can I store the object I get from getMyObject() somewhere so I don't have to call it repeatedly? I tried to use ng-init as:
<p ng-init="dataObject=getMyObject(item.DataId)"/>
and reference it like:
<input type="number"
ng-if="dataObject.Valid"
ng-model="dataObject.Price"/>
<div ng-bind="dataObject.Price"
ng-if="!dataObject.Valid"></div>
But this doesn't work once I submit any changes and change the data in the model since the ng-init only works on the first time when the page loads.

Answer 1

You could set up the one time binding in your linking function:
app.directive("myData", function() {
return {
restrict: "E",
templateUrl: "myTemplate.html",
link: function(scope) {
scope.dataObject = scope.getMyObject(scope.item.DataId);
}
};
});
This way you will have one dataObject per instanciation of your directive, but only computed once. Now if you need to "recompute" this dataObject after some change, you could do that in a function or on a watcher:
link: function(scope) {
scope.dataObject = scope.getMyObject(scope.item.DataId);
// Option 1
scope.$watch('somethingToWatch', function() {
scope.dataObject = scope.getMyObject(scope.item.DataId);
});
// Option 2 (choose one or the other)
scope.onSubmit = function() {
scope.dataObject = scope.getMyObject(scope.item.DataId);
};
}