$interval happening too many times - javascript

Hopefully I can explain this so you can understand. I just finished up a question getting help with angular's $interval functionality. Let's start from the basics first:
I have a dropdown where a user selects an option.
That action calls a select method which makes a $http.get( )
request.
The resulting data is then placed into a list using mg-repeat.
The data can be updated from another service, so I need this list to
periodically poll and refresh the list, enter $interval
In this code below, I am close, but not quite there. Say I want to refresh the list once every 10 seconds, if I choose option 1 from the start, it will refresh option 1's list every 10 seconds. Great right?
Now if I choose option 2, in terms that I understand, it seems like it creates another thread. It changes the $http.get( ) where it goes from option 1 to option 2, but it keeps option 1's $interval thread open. So it pings option 2's $http.get( ) twice in 10 seconds. Once following the time interval of the first request ever(for option 1) and once in the interval of me selecting option 2.
Here is the JS code for the select function. This happens when a user selects something from the dropdown:
$scope.select = function() {
$scope.searchText = '';
$scope.selectedItem = null;
var url = 'http:xxxxxxxxxxxx.com';
url += $scope.selectModel.name;
console.debug("GOING TO: " + url);
$http.get(url).success(function(data2) {
$scope.records = [];
data2.forEach(function(r) {
$scope.records.push(r);
});
});
$interval(function() {
$http.get(url).success(function(data2) {
$scope.records = [];
data2.forEach(function(r) {
$scope.records.push(r);
});
});
}, 30000);
};
And here is the section of html in question:
<div style="margin: 1em">
<h4>Search</h4>
<div role="form">
<!-- start dropdown -->
<div class="form-group">
<select class="form-control" ng-options="model as model.name for model in allModels" ng-model="selectModel" ng-change="select()">
<option value="">Choose Model</option>
</select>
</div>
<!-- /end dropdown-->
<div class="form-group">
<input id="start_date" type="text" class="form-control" placeholder="Threat Date">
</div>
</div>
<div>
<table class="table table-hover table-striped" ng-show="records">
<thead>
<th>#</th>
<th>Name</th>
<th>Score</th>
</thead>
<tr data-ng-repeat=" item in records | orderBy : '-score' | limitTo : 10 " ng-click="moreInfo(item)">
<td>{{$index+1}}</td>
<td>{{item.name.slice(5)}}</td>
<td>{{item.score.toFixed(3)}}</td>
</tr>
</table>
</div>
</div>
Let me know if i need to clarify some. Thanks.

You need to cancel your interval.
// Activate
var myInterval = $interval(....);
// Deactivate
$interval.cancel(myInterval);
myInterval = undefined; // Necessary for conditional checking

Related

Retrieving the id from Model to Controller in Angular JS

i have a table which is having the data retrieved from an api call from my memberController which is displayed inside ng-repeat and its working fine.
I need each Business Name of the member list to link to a separate page(edit_form.html) and display the id value, so that i can pass this along with the api call to get only this particular member detail. So i have added ng-init in my edit form page which calls the function test_funct when the page loads and retrieve each persons id there. unfortunately i am unable to retrieve the id value inside the function.
HTML Template
<div class="page" data-ng-controller="memberController">
<table>
<thead >
<tr>
<th>Business Name</th>
<th>Contact Name</th>
<th>Trade Balance</th>
<th>Cash Balance</th>
<th>Telephone</th>
<th>Account Number </th>
</tr>
</thead>
<tbody>
<tr data-ng-repeat="member in details | filter:search">
<td>{{member.businessname}}</td>
<td>{{member.person}}</td>
<td>{{member.balance_trade}}</td>
<td>{{member.balance_cash}}</td>
<td>{{member.telephone}}</td>
<td>{{member.accountnumber}}</td>
</tr>
</tbody>
</table>
</div>
I have the following controller
function memberController($scope, $http, $cookieStore) {
var token = $cookieStore.get('token');
var conId = $cookieStore.get('Cont_Id');
var exId = $cookieStore.get('ex_Id');
var member_list = "http://www.vb.com/functions/member_list.html?exchangeid=" + exId +
"&contactid=" + conId + "&token=" + token;
$http.get(member_list)
.success(function(response) {
$scope.details = response;
});
$scope.test_funct = function(id) {
$scope.myid = id;
alert($scope.myid); // getting undefined in alert, i expect the id(eg:1123)
}
}
edit_form.html
<div class="page" data-ng-controller="memberController">
<div class="panel-body" ng-init="test_funct()"></div>
</div>
Please assist me on this. Thanks in advance.
There are 2 things going on here.
First, you should separate controllers for the different views, so you end up with something like this:
<div class="page" data-ng-controller="memberController">
<table>
<!-- your whole big table here -->
</table>
</div>
And your editing form as follows:
<div class="page" data-ng-controller="editController">
<div class="panel-body"></div>
</div>
Notice that you now have two distinct controllers - your "editController" and your "memberController".
The second question then becomes, how do you transfer the selected ID from the list view ("memberController") to the edit view ("editController").
There are 2 ways of doing that.
First, you could use a service shared between the controller:
.factory('SelectedId',function() {
return {};
});
And then in your "member" view, you would set it upon clicking:
{{member.businessname}}
Notice the ng-click, which then needs a function in the memberController and the injected service:
.controller('memberController',function($scope,SelectedId) {
$scope.setId = function(id) {
SelectedId.id = id;
};
});
While the editController retrieves it:
.controller('editController',function($scope,SelectedId) {
$scope.id = SelectedId.id;
});
The above option works well, especially for complex things like shopping carts. If all you are doing is passing an ID, I would just stick it in the URL:
{{member.businessname}}
So that the ID is part of the URL. You then can retrieve it in the "editController":
.controller('editController',function($scope,$routeParams) {
$scope.id = $routeParams.member;
});
assuming you are using ng-route, and your route would look like:
$routeProvider.when('/pages/edit_form/:member',{templateUrl:'/route/to/template.html',controller:'editController'});
In html do that
<td>{{member.businessname}}</td>
...
In app.js or where you define route do that
.when('/edit/:memberid',
{
templateUrl:'partials/edit.html',
controller:'editController'
})
In controller you have to take this id by doing that
app.controller("editController",function($routeParams,$scope){
$scope.memberid= $routeParams.memberid;
//Now use this member id to fetch all data
});

Angular controller not display data from JSON

I am using Angular and TingoDB (Mongo) inside Node Webkit for a single page application. However I have a strange problem that I have been unable to resolve.
When I use an object literal (option 2) the data displays correctly in the html page. However changing the code to return data from the database (option 1) the results do not appear on the html page. I have converted both styles of data into the a JSON string to prove consistency and then using the angular.fromJSON to return an object. Both methods return the same JSON string in console.log and before anyone asks I have either Option 1 or Option 2 commented out so both are not running concurrently.
I have copied the JSON string based on the data passed from TingoDB into the console.log and re-entered it into the code below to ensure that no differences between the 2 versions of the data existed without changing any other code, but the problem still persists.
Can anyone shed light on why this occurs and how to fix it?
var app = angular.module('myApp', []);
var Engine = require('tingodb')(),
assert = require('assert');
var db = new Engine.Db('./db', {});
var collection = db.collection("clean.db");
app.controller('tingoDataCtrl', ['$scope', function($scope) {
function getData(callback) {
//Option 1
collection.find().toArray(function(err, docs){
callback (JSON.stringify(docs));
});
//Option 2
var docs = [
{name:"tingo1", description:"56",_id:2},
{name:"tingo2", description:"33",_id:3},
{name:"tingo3", description:"22",_id:4},
{name:"tingo4", description:"76",_id:5},
{name:"tingo5", description:"99",_id:6}
];
callback (JSON.stringify(docs));
}
function info(b) {
// I'm the callback
console.log(b);
$scope.items = angular.fromJson(b)
}
getData(info);
}]);
And the Html
<body ng-app="myApp" id="main">
<div class="page page-data ng-scope">
<section class="panel panel-default" ng-controller="tingoDataCtrl">
<div class="panel-heading"><span class="glyphicon glyphicon-th"></span> Tingo Data</div>
<table class="table">
<thead>
<th class="col-md-4">
Name
</th>
<th class="col-md-8">
Description
</th>
<th class="col-md-8">
ID
</th>
<th></th>
<tr>
</tr>
</thead>
<tbody>
<!-- <tr class="reveal-animation" ng-repeat="item in items | filter:query"> -->
<tr ng-repeat="item in items | filter:query">
<td>{{item.name}}</td>
<td>{{item.description}}</td>
<td>{{item._id}}</td>
</tr>
</tbody>
</table>
</section>
</div>
<script src="js/tingo_problem.js"></script>
</body>
TingoDB is an asynchronous API which will work in the background without stop your app. This means that a syncronous code have no time to wait for an answer and in return it gives undefined.
In your case, you have done a asynchronous call, and it returns correctly the answer to the memory, but too late, the DOM have been updated with undefined already even if your javascript has the data (try console.log to see that it was there).
Angular has a way to be forced to update again the DOM with the new elements of the controller. it is called $apply. And the best way to use it to avoid unexpected behaviours is:
function info(b) {
// I'm the callback
console.log(b);
$scope.items = angular.fromJson(b);
if (!$scope.$$phase) {
$scope.$apply(); //forces update the view
}
}//$scope is NECESARY to be defined in the controler, avoid using it with "ControlerAs"

How to retrieve text from several input fields with same ng-model in Angular

I have a page that displays an input field after the user clicks a button. If the user clicks the same button several times, the application will spawn the same input field several times. Likewise, there is a button to remove the last input field that was added.
After the user has spawned and filled out as many input fields as they want, I want the user to be able to click a button whose action will then be to gather all the information from the input fields, and do a console.log() of all that information. How would I go about doing this in Angular.js?
Here is the way I am currently doing the part where I add/remove input fields, and my attempt at gathering the data from the view.
<div ng-app="" ng-controller="myController">
<button ng-click="add()">Click Me to Add!</button>
<button ng-click="rem()">Click Me to Remove!</button>
<div ng-repeat="x in obj">
<label>Input 1</label><input type="text" ng-model="thing">
</div>
<button ng-click="display()">display</button>
</div>
<script>
function myController($scope){
$scope.obj = [];
$scope.count = 0;
$scope.add = function(){
$scope.count = $scope.count + 1;
$scope.obj.push({lett: $scope.count});
};
$scope.rem = function(){
$scope.count = $scope.count - 1;
$scope.obj.pop();
};
$scope.display = function(){
console.log($scope.thing);
};
}
</script>
The part where I do ng-model="thing" is my attempt to bind the data from the view, to the application. $scope.display is the function that is supposed to do the displaying.
Thanks in advance for your responses!
I rewrote some of your code to make it work:
<div ng-app="" ng-controller="myController">
<button ng-click="add()">Click Me to Add!</button>
<button ng-click="rem()">Click Me to Remove!</button>
<div ng-repeat="input in inputs track by $index">
<label>Input {{ $index }}</label>
<input type="text" ng-model="input.value" />
</div>
<button ng-click="display()">display</button>
</div>
<script>
function myController($scope){
$scope.inputs = [];
$scope.add = function(){
$scope.inputs.push({'value':''});
};
$scope.rem = function(){
$scope.inputs.pop();
};
$scope.display = function(){
console.log($scope.inputs);
};
}
</script>
You can see the fiddle here:
http://jsfiddle.net/K38GC/
To get the display the way you want it you can edit the $scope.display function to fit whatever you'd like. Let me know if you have any questions.

Simple $scope.$watch not called?

I have a simple table app which gets JSON data from a database. It passes the data via parameter to my app controller, which then filters the data. This works great. However, it is a lot of data (hundred thousand objects). I have search boxes that I use to try and filter the data, and when the search watch should be getting called (when someone types something in the search box), it doesn't. Am I missing something?
js:
var app = angular.module('SortingTables', ['ui.bootstrap']);
//Dependencies which are services, providers or factories must map to string types, which are then passed into the instance function
app.filter('startFrom', function () {
return function (input, start) {
start = +start; //parse to int
return input.slice(start);
};
});
app.controller('Ctrl', function ($scope, filterFilter, dataTable) {
$scope.currentPage = 1;
$scope.itemsPerPage = 25;
$scope.totalItems = 0;
$scope.predicate = '';
$scope.searchBuffer = {
$: ''
};
$scope.filtered;
//This function has sort of been abstracted...
//The purpose of this function is to delay the update so the user gets a chance to finish typing before the filter is applied.
//Newer versions of angularjs have the ng-model-options: debounce=100 but we can't use that since we have IE 8 on dev boxes
$scope.$watch('searchBuffer', function (term) {
console.log('The watch on searchBuffer was called');
$scope.filtered = filterFilter(dataTable, term);
$scope.totalItems = $scope.filtered.length;
});
$scope.pageChanged = function () {
$scope.currentRow = $scope.currentPage * $scope.itemsPerPage - $scope.itemsPerPage;
};
});
html
<div ng-app="Components" ng-controller="Ctrl">
<hr/>
<table class="table table-striped">
<tr>
<th>Technical Owner
<br />
<input type="search" ng-model="searchBuffer['Technical Owner']">
</a>
</th>
<th>Branch
<br />
<input type="search" style="width: 40px" ng-model="searchBuffer.Branch">
</a>
</th>
<th>Sub Pillar
<br />
<input type="search" ng-model="searchBuffer['Sub Pillar']">
</a>
</th>
<th>Path
<br />
<input type="search" ng-model="searchBuffer.Path">
</a>
</th>
<th>Name
<br />
<input type="search" ng-model="searchBuffer.Name">
</a>
</th>
<th>Description
<br />
<input type="search" ng-model="searchBuffer.Description">
</a>
</th>
</tr>
<tr ng-repeat="ComponetOwner in filtered | startFrom:currentPage | orderBy:predicate:reverse | limitTo:itemsPerPage">
<td>{{ComponetOwner["Technical Owner"]}}</td>
<td>{{ComponetOwner.Branch}}</td>
<td>{{ComponetOwner["Sub Pillar"]}}</td>
<td>{{ComponetOwner.Path}}</td>
<td>{{ComponetOwner.Name}}</td>
<td>{{ComponetOwner.Description}}</td>
</tr>
</table>
<pagination items-per-page="itemsPerPage" total-items="totalItems" ng-model="currentPage" ng-change="pageChanged()"></pagination>
</div>
When I type something in the search box, $watch doesn't get called. What's going on?
searchBuffer is an object. The third optional argument of $watch needs to be set to 'true' for watching objects/arrays (that is for deep watching).
Read this:
$watch an object
You can do $watchCollection which will watch all the objects within an object.
Not as deep as setting the third optional argument which is true for yout $watch function.
Here is a good blog about it: http://www.bennadel.com/blog/2566-scope-watch-vs-watchcollection-in-angularjs.htm

Using knockoutJS, how to bind list items to same view?

I am new to Knockout and I am building a Simple POC for using knockout to build SPA(Single Page Application).
What I want to do is to show "Business Units" when the app loads and on selection of a business unit show all "Front End Units" under that business unit and on selection of a front end unit, show all "Sales Segments" under that front end unit.
All this will happen in a single page using the same view and the viewmodel will bind the model based on selected business unit or front end unit.
The issue I am facing is that, I have 5 business units that get bound properly first on document ready, but on selection of business unit, the front end units get repeated 5 times each. In this case, I have 2 front end units and each is shown 5 times. Same issue on selection of front end unit.
You can see this issue mimicked in the following jsFiddle sample - jsFiddle Link
Let me know if you can't access the jsfiddle link. In this sample, I have used arrays, but in actual I will be getting the data through async call to the oData service.
This is the view HTML:
<div id="divbu">
<h4 data-bind="text: Heading"></h4>
<ul data-role="listview" data-inset="true" data-bind="foreach: Collection">
<li data-role="list-divider" data-bind="text: EntityName"></li>
<li>
<a href="#" data-bind="click: $root.fnNextLevel">
<table border="0">
<tr>
<td>
<label style="font-size: 12px;">Bus. Plan: </label>
</td>
<td>
<label style="font-size: 12px;" data-bind="text: BusinessPlan"></label>
</td>
<td>
<label style="font-size: 12px;">Forecast: </label>
</td>
<td>
<label style="font-size: 12px;" data-bind="text: Forecast"></label>
</td>
</tr>
<tr>
<td>
<label style="font-size: 12px;">Gross Sales: </label>
</td>
<td colspan="3">
<label style="font-size: 12px;" data-bind="text: GrossSales"></label>
</td>
</tr>
</table>
</a>
</li>
</ul>
</div>
This is the model and view model:
function CommonModel(model, viewType) {
var self = this;
if (viewType == 'BU') {
self.EntityName = model[0];
self.BusinessUnit = model[0];
self.BusinessPlan = model[1];
self.Forecast = model[2];
self.GrossSales = model[3];
} else if (viewType == 'FEU') {
self.EntityName = model[1];
self.BusinessUnit = model[0];
self.FrontEndUnit = model[1];
self.BusinessPlan = model[2];
self.Forecast = model[3];
self.GrossSales = model[4];
} else if (viewType == 'SS') {
self.EntityName = model[2];
self.BusinessPlan = model[3];
self.Forecast = model[4];
self.GrossSales = model[5];
}
}
function ShipmentReportsViewModel(results, viewType) {
var self = this;
self.Collection = ko.observableArray([]);
for (var i = 0; i < results.length; i++) {
self.Collection.push(new CommonModel(results[i], viewType));
}
if (viewType == 'BU') {
self.Heading = "Business Units";
self.fnNextLevel = function (businessUnit) {
FetchFrontEndUnits(businessUnit);
};
self.Home = function () {
FetchBusinessUnits();
};
} else if (viewType == 'FEU') {
self.Heading = results[0][0];
self.fnNextLevel = function (frontEndUnit) {
FetchSalesSegments(frontEndUnit);
};
self.Home = function () {
FetchBusinessUnits();
};
} else if (viewType == 'SS') {
self.fnNextLevel = function () {
alert('No activity zone');
};
self.Heading = results[0][0] + ' - ' + results[0][1];
self.Home = function () {
FetchBusinessUnits();
};
}
}
You can see the complete code in the jsFiddle link.
I have also tried this with multiple views and multiple view models, where I apply bindings by giving the element ID. In this case, one flow from business unit -> sales segment is fine, but when I click on home or back button and I do binding again to that element, I face the same issue. (home and back button features are not done in jsFiddle example).
Let me know if more details are required. I did look into lot of other links in stack overflow, but nothing addressing this particular problem.
Any help is deeply appreciated. Thanks in advance.
The problem here is that you call your ko.applybindings TWICE and there is a foreach binding that iterate within 5 items, therefore the data are duplicated five times.
you should not call a ko.applybindings more than once on the same model.
Your model is always the same even if it's parametrized.
I had the same problem here: Data coming from an ObservableArray are displayed twice in my table
the fact that you have you business logic inside your viewModel is something that could be discussed, and it makes it not easy to fix this.
Make 3 classes, put them in a common model without logic inside. Then once you have applyed the ko.applyBindings once, you just have to modify the array like this:
viewModel.myArray(newValues)
Here is the fiddle with the amended code: http://jsfiddle.net/MaurizioPiccini/5B9Fd/17/
it does not do exaclty what you need but if remove the multiple bindings by moving the Collection object scope outside of your model.
As you can see the problem IS that you are calling the ko.applybindings twice on the same model.
Finally, I got this working. Thanks to #MaurizioIndenmark.
Though I have removed multiple call for ko.applybindings, I was still calling the view model multiple times. This was causing the issue.
Now, I have cleaner view model and I have different function calls for different actions and modify all the data required to be modified within these functions(events). Now, everything is working as expected.
This is how the view model looks now -
function ShipmentReportsViewModel(results) {
var self = this;
self.Heading = ko.observable();
self.BusinessUnits = ko.observableArray();
self.FrontEndUnits = ko.observableArray();
self.SalesSegments = ko.observableArray();
self.Home = function () {
var bu = FetchBusinessUnits();
self.Heading("Business Units");
self.BusinessUnits(bu);
self.FrontEndUnits(null);
self.SalesSegments(null);
};
self.fnFeu = function (businessUnit) {
var feu = FetchFrontEndUnits(businessUnit);
self.Heading(feu[0].BusinessUnit);
self.FrontEndUnits(feu);
self.BusinessUnits(null);
self.SalesSegments(null);
};
self.fnSalesSeg = function (frontEndUnit) {
var ss = FetchSalesSegments(frontEndUnit);
self.Heading(ss[0].BusinessUnit + ' - ' + ss[0].FrontEndUnit);
self.SalesSegments(ss);
self.BusinessUnits(null);
self.FrontEndUnits(null);
};
self.Home();
}
To see the entire working solution, please refer this jsFiddle
Thanks for all the valuable suggestions in getting this work.

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