//Define current window
var currentWin = Ti.UI.currentWindow;
 
//Define a button to strat the progress
var stratBtn = Ti.UI.createButton({
      width   :   200,
      height   : 50,
      title      : 'Strat Progress', 
      top      : 300
});
 
//Button added to window
currentWin.add(stratBtn);
 
//Define a slider
var sliderAsProgressbar = Titanium.UI.createSlider({
      width      : 300,
      min      : 0,               // Minimum value dispayed on  the bar
      max      : 100            // Maximum value dispayed on  the bar
});
 
//Set the thumb image with any transparent image
sliderAsProgressbar.thumbImage = 'transparentImage.png';
 
//Asign initial value to the bar
sliderAsProgressbar.value = 0;
 
//Disable slider for touch effect
sliderAsProgressbar.touchEnabled = false;
 
//Bar added to window
currentWin.add(sliderAsProgressbar);
 
//Event to start progress
stratBtn.addEventListener('click', function(){
   
      //Asign initial value to the bar
      sliderAsProgressbar.value = 0;
 
      var cahangedVal = 0, progressInterval;
 
      //Check the progress interval
      if (progressInterval) {
         clearInterval(progressInterval);
     }
 
      //Do the progress stuff
     progressInterval= setInterval(function() {
      
         //Condition to check max value
         if (val >= 101) {
            //Stop the progressing
             clearInterval(progressInterval);
 
             //Asign initial value to the bar
            sliderAsProgressbar.value = 0;
             return;
      }
 
         //Change the bar value to show progress
         sliderAsProgressbar.value = cahangedVal ;
         cahangedVal++;
 
     }, 1000);
});
 
NOTE : Tested in Android, IOS, Mobileweb.