Material select is not enabled on button click

I have a material select which binds the data using angular, on page load I disabled the Material select, on button click am enabling the material select.

Issue : Material Select is not enabled

````HTML

var app = angular.module('materializeApp', ['ui.materialize'
.controller('BodyController', ["$scope", function ($scope) {
$scope.projects = {
value: "Select Value",
choices: ["p1", "p2", "p3", "p4"]
};

debugger;
$scope.checked = true;
$scope.edit = function () {
$scope.checked = false;
}

}]);

````

Start with the provided AngularJS example, focusing on the material-select directive and the edit() click handler that changes checked from true to false. Verify the directive's behavior when ng-disabled changes after page load; done means the Material select becomes usable after clicking Edit.

Written by the indexing model from the issue text.