Undefined touch using ngDraggable (AngularJS)

I am developing an app with AngularJS and a component called ngDraggable but I am having problems with touch events. When the touch event for drag is fired, the console displays an error:

Uncaught TypeError: Cannot read property '0' of undefined    ngDraggable.js:118
onlongpress   ngDraggable.js:118
(anonymous function) ngDraggable.js:95

      

        
        
        
      

    

I have already tried to debug the code and the variable evt

does not have an array touches

like in the example codes.

Does anyone have any ideas how I can solve this problem?

Below is the snippet where the code is the problem:

var onlongpress = function(evt) {
   if(! _dragEnabled)return;
   evt.preventDefault();
   element.addClass('dragging');
   offset = _privoffset(element); 
   element.centerX = element[0].offsetWidth / 2;
   element.centerY = element[0].offsetHeight / 2;    
   _mx = (evt.pageX || evt.touches[0].pageX);        // <---- This is the line the problem occurs
   _my = (evt.pageY || evt.touches[0].pageY);
   _mrx = _mx - offset.left;
   _mry = _my - offset.top;
   if (_centerAnchor) {
       _tx = _mx - element.centerX - $window.pageXOffset;
       _ty = _my - element.centerY - $window.pageYOffset;
   } else {
       _tx = _mx - _mrx - $window.pageXOffset;
       _ty = _my - _mry - $window.pageYOffset;
   }
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