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Ionic and Angularjs - Update/Refresh View from Controller

The usual start to these, I am new to both Ionic and Angularjs. I am developing an Ionic app which at it's heart is very simple. We show a list of classes(sessions), the person clicks on an icon to book the class then the icon changes to allow them to cancel the class. We also update the card to show the number of places remaining in each session on the day.
I have the code working to add and remove a person to and from a class but I am not sure how to update the template view from within the controller.
The controller code is pretty simple
// Check Person in to session.
$scope.addCheckIn = function(schedule){
var promise = sessionDataService.checkinSession(schedule.sessionID);
promise.then(function(data){
// Update (refresh) Schedule Details
// NOT SURE WHAT TO PUT HERE??
});
};
I have tried a number of different approaches including
Refreshing the $state and calling doRefresh and even calling the original controller methods to populate the cards again but the view won't update unless I physically click between states on the screen
//$state.go('app.schedules', {}, {reload: true});
//$scope.doRefresh();
//getScheduleData(formatDate(selectedDate), formatDate(selectedDate), 'true');
I have also looked at $scope.apply and $scope.timeout but I am not sure if this is taking me further from the real solution
What is the correct way to update the view after an update? Should it be after the promise.then in the controller or should I call a service and update everything.
Any tips on what is the best way to do this and a point in the right would be really appreciated.
Thanks everyone.

In your promise, you should add the data to the scope.
$scope.scheduledetails = data;
Then in your template, you will be able to access the object scheduledetails from the controller with AngularJS brackets to bind the data to the HTML.
<h1>{{scheduledetails.title}}</h1>
<p>Details : {{scheduledetails.details}}</p>
AngularJS should take care of refreshing what is needed without having to call any method or anything.
Full example
Controller
$scope.addCheckIn = function(schedule){
var promise = sessionDataService.checkinSession(schedule.sessionID);
promise.then(function(data){
$scope.scheduledetails = data;
});
};
Template
<h1>{{scheduledetails.title}}</h1>
<p>Details : {{scheduledetails.details}}</p>

Meteor: Data from External API call not rendering

I am relatively new to Meteor, and I'm trying to create a web store for my sister-in-law that takes data from her existing Etsy store and puts a custom skin on it. I've defined all of my Meteor.methods to retrieve the data, and I've proofed the data with a series of console.log statements... So, the data is there, but it won't render on the screen. Here is an example of some of the code on the server side:
Meteor.methods({
...
'getShopSections': function() {
this.unblock();
var URL = baseURL + "/sections?api_key="+apiKey;
var response = Meteor.http.get(URL).data.results;
return response;
}
...
});
This method returns an array of Object. A sample bit of JSON string from one of the returned Objects from the array:
{
active_listing_count: 20,
rank: 2,
shop_section_id: 1******0,
title: "Example Title",
user_id: 2******7
}
After fetching this data without a hitch, I was ready to make the call from the client side, and I tried and failed in several different ways before a Google search landed me at this tutorial here: https://dzone.com/articles/integrating-external-apis-your
On the client side, I have a nav.js file with the following bit of code, adapted from the above tutorial:
Template.nav.rendered = function() {
Meteor.call('getShopSections', function(err, res) {
Session.set('sections', res);
return res;
});
};
Template.nav.helpers({
category: function() {
var sections = Session.get('sections');
return sections;
}
});
And a sample call from inside my nav.html template...
<ul>
{{#each category}}
<li>{{category.title}}</li>
{{/each}}
</ul>
So, there's a few things going on here that I'm unsure of. First and foremost, the DOM is not rendering any of the category.title String despite showing the appropriate number of li placeholders. Secondly, before I followed the above tutorial, I didn't define a Session variable. Considering that the list of shop categories should remain static once the template is loaded, I didn't think it was necessary from what I understand about Session variables... but for some reason this was the difference between the template displaying a single empty <li> tag versus a number of empty <li>'s equal to category.length --- so, even though I can't comprehend why the Session variable is needed in this instance, it did bring me one perceived step closer to my goal... I have tried a number of console.log statements on the client side, and I am 100% sure the data is defined and available, but when I check the source code in my Developer Tools window, the DOM just shows a number of empty li brackets.
Can any Meteor gurus explain why 1) the DOM is not rendering any of the titles, and 2) if the Session variable indeed necessary? Please let me know if more information is needed, and I'll be very happy to provide it. Thanks!

You set the data context when you use #each, so simply use:
<li>{{title}}</li>
If a Session is the right type of reactive variable to use here or not is hard to determine without knowing what you are doing but my rough guess is that a Mini Mongo collection may be better suited for what it appears you are doing.
To get you started on deciding the correct type of reactive variable to use for this head over to the full Meteor documentation and investigate: collections, sessions, and reactive vars.
Edit: To step back and clarify a bit, a Template helper is called a reactive computation. Reactive computations inside of helpers will only execute if they are used in their respective templates AND if you use a reactive variable inside of the computation. There are multiple types of reactive variable, each with their own attributes. Your code likely didn't work at all before you used Session because you were not using a reactive variable.

Creating a controller/service to persist data, with information from the DOM

In angular I have in a view a list of items which will be display in another view depending on whether they are checked or not.
this is the view where you check which sports you want to display in the another view
<ion-item ng-repeat="sport in sports"
ng-init="sport.checked = true"
ng-click="sport.checked = !sport.checked">
{{:: sport.name}}
</ion-item>
this is the another view
<div ng-show="sport.checked"
ng-repeat="sport in sports">
{{sport.name}}
</div>
as you see all those sports has an ng-init = sport.checked = true, so all the sports are shown at the beginning but you can unchecked those sports in order to don't see them until you checked it again.
that's all I have so far and works, but once you refresh the page, all the checks and unchecks die, everything restarts after refreshing, so as you know I need to persist that data in a DB or something, I am using node.js/sails.js along with Redis for this. I have an idea of how to create almost everything in the node.js part, but I need some help in the Angular part with the controller and the service, so I need your help here.
I want that the users are able to checked their sports only once, and not every time they log in on the app.
So what functions can I add to the controller to advise to the service when a sport has been unchecked, and how the service will be receiving that data ?
also, if you have any suggestions for the NodeJS part, that would be awesome too.

Here is an example of what you could use. This is very bareboned. All the $http fucntions work with promises. The controller will get the settings from the service when, if that is empty it requests new settings from the service
angular.module('app').controller('appctrl',['appsrv','$scope',function(appsrv, $scope){
$scope.settings = service.settings;
if(!$scop.settings){
//retrieve data from server when it's not in the service
appsrv.getSettingsRemote().then($scope.settings = service.settings);
}
}]).service('appsrv',[$http, function($http){
return {
getSettings : function (){
// get settings from localstorage
},
setSettings : function (){
// store settings to localstorage
},
getSettingsRemote : function () {
$http.get('url').then(//set things locally);
}
}
}]);
Then from your view you could just assign the controller to the view and then reference to your settings like {{settings.propname}}
I don't want to write all your code but maybe this has given you insight in what you could do

How to redirect to different controller?

I have an application in ASP.MVC. The requirement is that I select a person from a list of people and click 'Info' and it should load the details of the person in that page. I have the Info controller and everything works fine if I go to the Info page from a different controller. In the page I am trying to make it work with JavaScript and it doesn't seem to take me to the desired page but to a different controller.
I have a ToDoList controller and in the .cshtml I have this code on click of the Info link.
function DoInfo#(i.ToString())() {
$("#sessionid").val("#Model.cSessionId[i]");
alert("hey");
$("#PageController").val(66);
$("#formID").submit();
}
I go to the ToDoList controller to do the redirection like this
if (viewModel.PageController == 66)
{
pass = new PassingData();
pass.personid = TSSessionService.ReadPersonId(viewModel.SessionId);
TempData["pass"] = pass;
return RedirectToAction("Index", "Info");
}
It never goes there and instead goes to a different controller. I cannot seem to find how they are linked and why is it not going back to controller where the Info link button is i.e. back to the ToDoList controller.
Let me know if it is not clear and I will try to explain again and I will give any other details.

I guess I'm confused as to why you are doing this as a combination of form and JavaScript. Are there other properties that you need to pass along that you are not posting above? Why do you need to use JavaScript to do this if you are just returning a new view?
You indicate in your post that when a person is selected from a list you need to go to a controller and display a view. This seems fairly straightforward, and I would like to suggest simplifying the problem.
Start with this: change your link to not use a form or JavaScript. Just make it a link. If it is text, you can use #Html.ActionLink() and even pass in the parameters you need.
If you're not displaying text, just use #Url.ActionLink() in your href property of the anchor you're wrapping your element with. Both of these allow you to leverage routing to ensure the correct path is being constructed.
If the controller that you are trying to get to has access to whatever TSSessionService is, then you don't need to pass through the TempData["pass"] you are trying to push through, so it makes it cleaner in that way as well.
If you do need to submit a more complicated value set, I would recommend coming up with a generic .click() event handler in jQuery that can respond to any of the clicks, bound by a common class name. You can use a data-val attribute in your link and read from $(this).attr('data-val') in your handler to store/fetch other important info. This allows you to more easily build up an object to POST to a controller.
Hope this helps some, but if I'm missing a critical point then please update the question above.

backbone.js cache collections and refresh

I have a collection that can potentially contain thousands of models. I have a view that displays a table with 50 rows for each page.
Now I want to be able to cache my data so that when a user loads page 1 of the table and then clicks page 2, the data for page 1 (rows #01-50) will be cached so that when the user clicks page 1 again, backbone won't have to fetch it again.
Also, I want my collection to be able to refresh updated data from the server without performing a RESET, since RESET will delete all the models in a collection, including references of existing model that may exist in my app. Is it possible to fetch data from the server and only update or add new models if necessary by comparing the existing data and the new arriving data?

In my app, I addressed the reset question by adding a new method called fetchNew:
app.Collection = Backbone.Collection.extend({
// fetch list without overwriting existing objects (copied from fetch())
fetchNew: function(options) {
options = options || {};
var collection = this,
success = options.success;
options.success = function(resp, status, xhr) {
_(collection.parse(resp, xhr)).each(function(item) {
// added this conditional block
if (!collection.get(item.id)) {
collection.add(item, {silent:true});
}
});
if (!options.silent) {
collection.trigger('reset', collection, options);
}
if (success) success(collection, resp);
};
return (this.sync || Backbone.sync).call(this, 'read', this, options);
}
});
This is pretty much identical to the standard fetch() method, except for the conditional statement checking for item existence, and using add() by default, rather than reset. Unlike simply passing {add: true} in the options argument, it allows you to retrieve sets of models that may overlap with what you already have loaded - using {add: true} will throw an error if you try to add the same model twice.
This should solve your caching problem, assuming your collection is set up so that you can pass some kind of page parameter in options to tell the server what page of options to send back. You'll probably want to add some sort of data structure within your collection to track which pages you've loaded, to avoid doing unnecessary requests, e.g.:
app.BigCollection = app.Collection.extend({
initialize: function() {
this.loadedPages = {};
},
loadPage: function(pageNumber) {
if (!this.loadedPages[pageNumber]) {
this.fetchNew({
page: pageNumber,
success: function(collection) {
collection.loadedPages[pageNumber] = true;
}
})
}
}
});

Backbone.Collection.fetch has an option {add:true} which will add models into a collection instead of replacing the contents.
myCollection.fetch({add:true})
So, in your first scenario, the items from page2 will get added to the collection.
As far as your 2nd scenario, there's currently no built in way to do that.
According to Jeremy that's something you're supposed to do in your App, and not part of Backbone.
Backbone seems to have a number of issues when being used for collaborative apps where another user might be updating models which you have client side. I get the feeling that Jeremy seems to focus on single-user applications, and the above ticket discussion exemplifies that.
In your case, the simplest way to handle your second scenario is to iterate over your collection and call fetch() on each model. But, that's not very good for performance.
For a better way to do it, I think you're going to have to override collection._add, and go down the line dalyons did on this pull request.

I managed to get update in Backbone 0.9.9 core. Check it out as it's exactly what you need http://backbonejs.org/#Collection-update.