function resizeIframe(){
  var myHeight = 0;
  if(typeof(window.innerHeight) == 'number' ){
    myHeight = window.innerHeight;
  } else if(document.documentElement && document.documentElement.clientHeight){
    myHeight = document.documentElement.clientHeight;
  } else if( document.body && document.body.clientHeight){
    myHeight = document.body.clientHeight;
  }
  myHeight = myHeight - 38;
  document.getElementById('iframe').style.height = myHeight + 'px';
}