AngularJS truncate ng-option values from select menu

Question

I have an Angular Bootstrap select plugin applied to my select menus, which renders the selected menu item into the following:

            <button data-toggle="dropdown" class="btn btn-default dropdown-toggle" type="button">
                <div class="filter-option pull-left">Item with a very long name</div>&nbsp;<div class="caret"></div>
            </button> 

I'm trying to develop a function that will truncate a selected menu item name if it is greater than a specified length.

The function:

            $scope.truncate = function(){
                    var maxLength = 5;
                    $('button .filter-option').text(function(i, text) {
                        if (text.length > maxLength) {
                            return text.substr(0, maxLength) + '...';  
                        }
                    }); 
            }

The function called on the original select markup in the Angular template:

            <select
                class="nya-selectpicker"
                ng-model="items"
                ng-options="g.name for g in myItems"
                ng-change="truncate()">
                <option value="">Select</option>
            </select>

My issue: It's not truncating the item I selected from my menu; it's truncating the default items of the two adjacent select menus in my template.

How can I update this function to truncate the item I select from my menu?

Answer 1

So essentially you need to create a filter. You can then apply this filter in the ng-options .

ng-options="(g.name | myFilter) for g in myItems"

myApp.filter('myFilter', function() {
  return function(val) {
    var maxLength = 5;
    if (val > maxLength) {
      return val.substr(0, maxLength) + '...';  
    } else {
      return val;
    }
  };
});

You could instead apply a filter to the array (I like the previous example better)

ng-options="g.name for g in myItems | myFilter"

myApp.filter('myFilter', function() {
  var maxLength = 5;
  return function(arr) {
    var returnArr = [];
    for(var i = 0; i < arr.length; i++) {
      (function() {
        var item = {};
        angular.copy(arr[i], item);
        if (item.name > maxLength) {
          item.name = item.name.substr(0, maxLength) + '...';
        }
        returnArr.push(item);  
      })();
    }
    return returnArr;
  };
});