Javascript touch movement, track when user swipes from edges

Question

I need to track user touch events. I want to track when user swipes from edges.
For example when user swipes from left vertical edge I will show a menu, from right edge

Answer 1

I think this will work:

first check if the touchstart event happens at the edge of the screen:

var startDragAtBorder = false;
$(document).on('touchstart', function(e) {
   var xPos = e.originalEvent.touches[0].pageX;

   if(xPos < 5) { // this can also be xPos == 0; whatever works for you
    startDragAtBorder = true;   
   }
   else{
    startDragAtBorder = false;
   }
});

than setup the drag event with Hammer:

$(document).hammer().on('drag', function(e){
  if(startDragAtBorder && e.gesture.direction == 'right'){
    // check that the drag event started at the edge and that the direction is to the right

    var currentText = $('#logArea').text();   
    $('#logArea').text(""+currentText+" . "+e.type);
  }
});

working fiddle: http://jsfiddle.net/ym4JV/55/