// Auto-select listbox

// This script and the listbox on this page illustrates one
// way to create an "auto-complete" listbox, where the

var toFind = "";              // Variable that acts as keyboard buffer
var timeoutID = "";           // Process id for timer (used when stopping
                              // the timeout)
timeoutInterval = 500;        // Milliseconds. Shorten to cause keyboard
                              // buffer to be cleared faster
var timeoutCtr = 0;           // Initialization of timer count down
var timeoutCtrLimit = 4 ;     // Number of times to allow timer to count
                              // down
var oControl = "";            // Maintains a global reference to the
                              // control that the user is working with.

function listbox_onkeypress(){
   // This function is called when the user presses a key while focus is in
   // the listbox. It maintains the keyboard buffer.
   // Each time the user presses a key, the timer is restarted.
   // First, stop the previous timer; this function will restart it.
   window.clearInterval(timeoutID)

   // Which control raised the event? We'll need to know which control to
   // set the selection in.
   oControl = window.event.srcElement;

   var keycode = window.event.keyCode;
   if(keycode >= 32 ){
       // What character did the user type?
       var c = String.fromCharCode(keycode);
       c = c.toUpperCase();
       // Convert it to uppercase so that comparisons don't fail
       toFind += c ; // Add to the keyboard buffer
       find();    // Search the listbox
       timeoutID = window.setInterval("idle()", timeoutInterval);
       // Restart the timer
    }
}

function listbox_onblur(){
   // This function is called when the user leaves the listbox.

   window.clearInterval(timeoutID);
   resetToFind();
}

function idle(){
   // This function is called if the timeout expires. If this is the
   // third (by default) time that the idle function has been called,
   // it stops the timer and clears the keyboard buffer

   timeoutCtr += 1
   if(timeoutCtr > timeoutCtrLimit){
      resetToFind();
      timeoutCtr = 0;
      window.clearInterval(timeoutID);
   }
}

function resetToFind(){
   toFind = ""
}


function find(){
    // Walk through the select list looking for a match

    var allOptions = document.all.item(oControl.id);

    for (i=0; i < allOptions.length; i++){
       // Gets the next item from the listbox
       nextOptionText = allOptions(i).text.toUpperCase();

       // By default, the values in the listbox and as entered by the
       // user are strings. This causes a string comparison to be made,
       // which is not correct for numbers (1 < 11 < 2).
       // The following lines coerce numbers into an (internal) number
       // format so that the subsequent comparison is done as a
       // number (1 < 2 < 11).

       if(!isNaN(nextOptionText) && !isNaN(toFind) ){
              nextOptionText *= 1;        // coerce into number
              toFind *= 1;
       }

        // Does the next item match exactly what the user typed?
        if(toFind == nextOptionText){
            // OK, we can stop at this option. Set focus here
            oControl.selectedIndex = i;
            window.event.returnValue = false;
            break;
        }

        // If the string does not match exactly, find which two entries
        // it should be between.
        if(i < allOptions.length-1){

           // If we are not yet at the last listbox item, see if the
           // search string comes between the current entry and the next
           // one. If so, place the selection there.

           lookAheadOptionText = allOptions(i+1).text.toUpperCase() ;
           if( (toFind > nextOptionText) &&
              (toFind < lookAheadOptionText) ){
              oControl.selectedIndex = i+1;
              window.event.cancelBubble = true;
               window.event.returnValue = false;
              break;
           } // if
           } // if

        else{

           // If we are at the end of the entries and the search string
           // is still higher than the entries, select the last entry

           if(toFind > nextOptionText){
               oControl.selectedIndex = allOptions.length-1 // stick it
                                                            // at the end
               window.event.cancelBubble = true;
               window.event.returnValue = false;
               break;
           } // if
       } // else
    }  // for
} // function



// add any other things you wish to load to this function
// please put try-catch blocks around them to ensure that if they are
// not present they do not break the page.
function loadPage()
{
  try
  {
    // start menu (LHS)
    startIt();
  }
  catch (Exception)
  {
    // do nothing on error (menu is not present)
  }

  try
  {
    // start scroller (RHS)
    tickinit();
  }
  catch (Exception)
  {
    // do nothing on error (scroller is not present)
  }

  try
  {
    // start scroller (RHS)
    runmikescroll();
  }
  catch (Exception)
  {
    // do nothing on error (scroller is not present)
  }
}

// load the menu and the scroller (and any other JS stuff that is required)
window.onload=loadPage;