c# - How to prevent PanoramaItem from swiping to the right in windows phone 8 xaml? -

i making tutorial page in xaml windows phone 8 app. tutorial build panoramaitems. problem users can swipe right , finish tutorial whitout following tutorial. want prevent this. got far:

private void firstitem_manipulationstarted(object sender, manipulationstartedeventargs e)     {         initialpoint = e.manipulationorigin;     }   private void firstitem_manipulationdelta(object sender, manipulationdeltaeventargs e)     {         point currentposition = e.manipulationorigin;         if(currentposition.x > initialpoint.x)         {             // block swipe or set item         }     } 

i know they've swipet right, how can block this?

private void panorama_selectionchanged(object sender, selectionchangedeventargs e) {     //set bool tutorial_not_finished = true once tutorial finished, false otherwise     if (tutorial_not_finished && ((panorama)sender).selectedindex == 3) //or whatever page count have         panoramacontrol.defaultitem = panoramacontrol.items[2]; //some else index last         //or can use "panoramacontrol.defaultitem = item2" item2 name in appropriate panoramaitem in xaml } 

don't have visual studio available right can't test this, should close enough.