trying to learn trying to learn - 2 months ago 10
AngularJS Question

AngularJs update data after adding new record

Which is the best way to update comments data when new record is added to database? i recently have this code which is working fine , but I am thinking that this way of coding may take long time if i have large amount of comments.Any help is appreciated

function addComment(comment){
dataservice.addComment(comment).then(function(response){
if(response.status == 200){
vm.getArticleComments(); // this will make new request to backend to fetch all comments
comment.body = '';
}else{
return false;
}
});
}


I was thinking to push new comment to view if response code is 200

Answer

IMO, Better use arrays instead.

Use unshift() method to prepend the ng-repeat list.

var data = [bar,bar2,bar3];
data.unshift(newItem);
//data = [newItem,bar,bar2,bar3];

Before doing this, make sure that you've successfully populated the database using $http.

As you said that you're think to push, that is also a good option but that will push the new data to the end of the list in the view.

Hope this helps you :)

var app = angular.module('app', []);

app.controller('MainCtrl', ['$scope', function ($scope) {
  $scope.items = [{
    name: '1',
    type: 'A'
  }, {
    name: '2',
    type: 'B'
  }];
  
  $scope.prependItem = function () {
    $scope.items.unshift({
      name: '3',
      type: 'C'
    });
  };
}]);
<!DOCTYPE html>
<html ng-app="app">

  <head>
    <meta charset="utf-8" />
    <title>AngularJS Plunker</title>
    <link rel="stylesheet" href="//netdna.bootstrapcdn.com/bootstrap/3.0.3/css/bootstrap.min.css" />
    <script>document.write('<base href="' + document.location + '" />');</script>
    <script src="//code.angularjs.org/1.2.6/angular.min.js"></script>
    <script src="//code.angularjs.org/1.2.6/angular-route.min.js"></script>
    <script src="app.js"></script>
  </head>

  <body ng-controller="MainCtrl">
    <div ng-repeat="item in items" watch-scope="item">
        <div class="someClass">Item name: {{item.name}}</div>
        <div class="anotherClass">Item type: {{item.type}}</div>
    </div>
    
    <button ng-click="prependItem()">Add New</button>
  </body>

</html>