Angular Data Table export to Excel using .withButtons:. Not able to see the buttons - angularjs

Question

I am trying to use angular datatables optionbuilder to create button for excel sheet download. But I am getting error withButton is not a function. I have downloaded all this files and have included in my main html page.
In HTML
<script src="/lib/angular-datatables.min.js"></script>
<script src="/lib/js_button/dataTables.buttons.min.js"></script>
<script src="/lib/js_button/buttons.flash.min.js"></script>
<script src="/lib/js_button/jszip.min.js"></script>
<script src="/lib/js_button/pdfmake.min.js"></script>
<script src="/lib/js_button/vfs_fonts.js"></script>
<script src="/lib/js_button/buttons.html5.min.js"></script>
<script src="/lib/js_button/buttons.print.min.js"></script>
<script src="/lib/angular-datatables.min.js"></script>
<link rel="stylesheet" type="text/css" href="/lib/js_button/buttons.dataTables.min.css">
In controller
var app = angular.module('myApp', ['Alertify','ngRoute', 'datatables']);
app.controller('MainCtrl', function($scope, $http, $location,
DTOptionsBuilder, DTColumnBuilder,Alertify) {..
$scope.vm.dtOptions = DTOptionsBuilder.newOptions()
.withOption('order', [])
.withOption('bFilter', false)
.withOption('bSort', false)
.withOption('bAutoWidth',true)
.withOption('sScrollY' , "200")
.withOption('sScrollX' , "100%")
.withOption('bScrollCollapse' , true)
.withPaginationType('full_numbers')
.withOption('lengthMenu', [5, 10, 25, 50, 100, 150, 200])
.withDOM('lrtip')
.withButtons([
{
extend: "excelHtml5",
filename: "MailItemList",
text: "<i class='fa fa-file-excel-o'></i> Excel",
title: "Mail Item List",
exportOptions: {
columns:[2,3,4,5,6,7,8.9,10,11,12,13,14,15,16,17,18,19,20,21,22]
},
exportData: { decodeEntities: true }
}
]);
..}
In Html
<table id="table1" class="table table-bordered table-hover fixed" datatable="ng" dt-columns="vm.dtColumns" dt-options="vm.dtOptions" >
<thead id="theadstyle">
<tr>
<th class="alignstyle"> </th>
<th class="alignstyle">1</th>
<th class="alignstyle">2</th>
<th class="alignstyle">3 </th>
<th class="alignstyle">4 </th>
<th class="alignstyle">5 </th>
<th class="alignstyle">6</th>
<th class="alignstyle">7 </th>
<th class="alignstyle">8</th>
</tr>
</thead>
<tbody >
<tr ng-repeat="build in buildmodel1">
<td> {{build.1}} </td>
<td> {{build.2}} </td>
<td> {{build.3}} </td>
<td> {{build.4}} </td>
<td> {{build.5}} </td>
<td> {{build.6}} </td>
<td> {{build.7}} </td>
<td> {{build.8}} </td>
</tr>
</tbody>
</table>
Can someone explain me what else needs to be added to this piece of code.

Answer 1

Adding B to dom, i.e .withDOM('Blrtip') will show buttons.
Error "withButtons is not a function" is because the js file dataTables.buttons.min.js is missing or , if you are in angular the module datatable.buttons is not defined
angular.module('app.components', [
...,'datatables.buttons']
Any remarks?