javascript - Use angular-translate to set placeholder value onblur -

i new angular. implementing localization in project. i've got many inputs , must translate placeholders. in html have this

<input  type="email" placeholder="{{ 'translation_key' | translate }}" onfocus="this.placeholder=''" onblur="this.placeholder='{{ 'translation_key' | translate }}'" required> 

but part of code doesn't work:(

onblur="this.placeholder='{{ 'translation_key' | translate }}'" 

how set translated value placeholder onblur? i'll appreciate help!

this approach problem jsfiddle:

html:

<div ng-app="myapp" ng-controller="myctrl">     <input  type="email" placeholder="{{placeholder}}" ng-focus="setplaceholder()" ng-blur="setplaceholder('translation_key')" required> </div> 

js:

angular.module('myapp', []) .controller('myctrl', function ($scope, $filter) {     $scope.placeholder = $filter('translate')('translation_key');      $scope.setplaceholder = function (data) {         $scope.placeholder = $filter('translate')(data);     }; }) .filter('translate', function () {     return function (data) {         return data;     }; });