Alert Example 1: Number Guessing Game

<div role="application">

  <script type="text/javascript">

  var guess1 = new Guess('guess1_text', 'guess1_check', 'guess1_again', 'guess1', 'alert1');
  widgets.add( guess1 );

</script>

<div id="guess1" class="guess">

  <h2>Number Guessing game</h2>
  
  <p><strong>Instructions:</strong> In this game you guess a number between 1 an 10 and then press the "Check My Guess" button to check your responses.  
    A <abbr title="Accessible Rich Internet Application">ARIA</abbr> dialog box will display the results of your guess.  To start over again to press the "Play Again" button.</p>

  <p class="input">
    <label for="guess1_text">Guess a number between 1 and 10</label>
    <input type="text" id="guess1_text" size="3" aria-invalid="false"/>
  </p>

  <p id="alert1" role="alert" class="feedback" >
    Make a guess
  </p>

  <p class="input">    
    <input class="button" id="guess1_check" type="button" value="Check My Guess"/>
    <input class="button" id="guess1_again" type="button" value="Play Again"/>
  </p>
</div>

</div>

  <script type="text/javascript">
/**
*
* The Globale Variables
*/

if (!window.Node) {
  var Node = {            // If there is no Node object, define one
    ELEMENT_NODE: 1,    // with the following properties and values.
    ATTRIBUTE_NODE: 2,  // Note that these are HTML node types only.
    TEXT_NODE: 3,       // For XML-specific nodes, you need to add
    COMMENT_NODE: 8,    // other constants here.
    DOCUMENT_NODE: 9,
    DOCUMENT_FRAGMENT_NODE: 11
  }
}


var KEY_PAGEUP   = 33;
var KEY_PAGEDOWN = 34;
var KEY_END      = 35;
var KEY_HOME     = 36;

var KEY_LEFT     = 37;
var KEY_UP       = 38;
var KEY_RIGHT    = 39;
var KEY_DOWN     = 40;

var KEY_SPACE    = 32;
var KEY_TAB      = 9;

var KEY_BACKSPACE = 8;
var KEY_DELETE    = 46;
var KEY_ENTER     = 13;
var KEY_INSERT    = 45;
var KEY_ESCAPE    = 27;

var KEY_F1        = 112;
var KEY_F2        = 113;
var KEY_F3        = 114;
var KEY_F4        = 115;
var KEY_F5        = 116;
var KEY_F6        = 117;
var KEY_F7        = 118;
var KEY_F8        = 119;
var KEY_F9        = 120;
var KEY_F10       = 121;

var KEY_M         = 77;

var NS_XHTML = "http://www.w3.org/1999/xhtml"
var NS_STATE = "http://www.w3.org/2005/07/aaa";

// **********************************************
// *
// * Commonly used helper functions
// *
// **********************************************

/**
*
* nextSiblingElement
*
* @contructor
*/

function nextSiblingElement( node ) {

  var next_node = node.nextSibling;

  while( next_node
    && (next_node.nodeType != Node.ELEMENT_NODE) ) {
    next_node = next_node.nextSibling;
  }  // endwhile

  return next_node;
  
}

/**
*
* previousSiblingElement
*
* @param ( node ) node object for which you are looking for the next sibling element node
*
* @return ( node) next sibling or "null"
*/

function previousSiblingElement( node ) {

  var next_node = node.previousSibling;

  while( next_node
    && (next_node.nodeType != Node.ELEMENT_NODE) ) {
    next_node = next_node.previousSibling;
  }  // endwhile

  return next_node;
  
}

/**
*
* firstChildElement
*
* @param ( node ) node object for which you are looking for the first child element node
*
* @return ( node) next sibling or "null"
*/

function firstChildElement( node ) {

  var next_node = node.firstChild;

  while( next_node
    && (next_node.nodeType != Node.ELEMENT_NODE) ) {
    next_node = next_node.nextSibling;
  }  // endwhile


  return next_node;
  
}

/**
*
* getTextContentOfNode
*
* @contructor
*/

function getTextContentOfNode( node ) {

  var next_node = node.firstChild;
  var str = "";

  while( next_node ) {
    
    if( (next_node.nodeType == Node.TEXT_NODE ) &&
      (next_node.length > 0 )
     )
      str += next_node.data;
    
    
    next_node = next_node.nextSibling;
    
  }  // endwhile

  return str;
  
}

/**
*
* setTextContentOfNode
*
* @contructor
*/

function setTextContentOfNode( node, text ) {

   // Generate a new text node with the text value
    var text_node = document.createTextNode(text);
  
    // Remove child nodes to remove text
    while (node.firstChild) {
      node.removeChild(node.firstChild);
    } // while

    // Append new text to the container element
    node.appendChild( text_node );

}
  </script>

  <script type="text/javascript">
// JavaScript Document
// Widgets is a way to initialize widgets in the ARIA examples


function Widgets() {
  this.widgets = new Array();
}

/**
* add is member of the Widgets Object
* and used add a widget ot the list of widgets to be intitialized
* as part of the onload event
* The controls array is the list of controls to initialize
* @member Enable
* @return none
*/

Widgets.prototype.add = function(obj) {
  this.widgets[this.widgets.length] = obj;
}

/**
* init is member of the Widgets Object
* and is called by the onload event to initialize widgets in the web resource
* The controls array is the list of controls to initialize
* @member Enable
* @return none
*/

Widgets.prototype.init = function() {
     
   for(var i = 0; i < this.widgets.length; i++ )
     this.widgets[i].init();
}

var widgets = new Widgets();

function initApp() {
  widgets.init();
}

  </script>

  <script type="text/javascript">
// JavaScript Document
// This module is to abstract browser dependencies
// This makes the widget code cleaner and earier to read by making most browser specfic coding
// in one place rather han scatered throghot documents
var ARIA_STATE = "aria-";

//
// WebBrowser object to abstract accessibility API differences between web standards supporting browsers and Internet Explorer 7.0
//
// The state variable keeps track of current state of checkbox
function WebBrowser() {

}


//
// keyCode is a function to get the keycode from a keypress event
//
// @param ( event object) event is an event object
//
// @return ( keycode )

WebBrowser.prototype.keyCode = function( event ) {
  var e = event || window.event;
  
  return e.keyCode;
}  

/**
* OnClick Event Simulator
*
* @param ( node ) DOM node object
* @return nothing
*/

if( document.createEvent ) {

  // If a web standards based browser implement this function

  WebBrowser.prototype.simulateOnClickEvent = function( node ) {
    // W3C DOM Events way to trigger a "click" event
    var e = document.createEvent('MouseEvents');
    e.initEvent( 'click', true, true );

    node.dispatchEvent( e );

  }

} else {

  // If a Microsoft IE based browser implement this function
  
  WebBrowser.prototype.simulateOnClickEvent = function( node ) {

    var e = document.createEventObject();
    node.fireEvent( "onclick", e );

  } // endif

}

if ( document.addEventListener ) {

  // If a web standards based browser implement this function

  WebBrowser.prototype.setMouseCapture = function( node, clickHandler, downHandler, moveHandler, upHandler ) {

    if( clickHandler )
      document.addEventListener( "click",     clickHandler, true );
    
    if( downHandler )
      document.addEventListener( "mousedown", downHandler,  true );

    if( moveHandler )
      document.addEventListener( "mousemove", moveHandler,  true );
    
    if( upHandler)
      document.addEventListener( "mouseup",   upHandler,    true );

  }

  WebBrowser.prototype.releaseMouseCapture = function( node, clickHandler, downHandler, moveHandler, upHandler ) {

  if( upHandler)
      document.removeEventListener( "mouseup",   upHandler,    true );
      
    if( moveHandler )
      document.removeEventListener( "mousemove", moveHandler,  true );
    
    if( downHandler )
      document.removeEventListener( "mousedown", downHandler,  true );
      
    if( clickHandler )
      document.removeEventListener( "click",     clickHandler, true );

  }

} else {

  // If a Microsoft IE based browser implement this function

  WebBrowser.prototype.setMouseCapture = function( node, clickHandler, downHandler, moveHandler, upHandler ) {

   node.setCapture();
   if( clickHandler)
     node.attachEvent( "onclick", clickHandler );
    
   if( downHandler)
     node.attachEvent( "onmousedown", downHandler );
    
   if( moveHandler )
     node.attachEvent( "onmousemove", moveHandler );
    
   if( upHandler )
     node.attachEvent( "onmouseup", upHandler );

  } // endif

  WebBrowser.prototype.releaseMouseCapture = function( node, clickHandler, downHandler, moveHandler, upHandler ) {

   if( upHandler )
     node.detachEvent( "onmouseup", upHandler );
    
   if( moveHandler )
     node.detachEvent( "onmousemove", moveHandler );
    
   if( downHandler)
     node.detachEvent( "onmousedown", downHandler );
    
   if( clickHandler)
     node.detachEvent( "onclick", clickHandler );
    
     node.releaseCapture();

  } // endif


}




if (typeof document.documentElement.setAttributeNS != 'undefined') {

  WebBrowser.prototype.stopPropagation = function( event ) {
    if( event.stopPropagation )
      event.stopPropagation();
    if( event.preventDefault )
      event.preventDefault();
    return false;
  }

  WebBrowser.prototype.target = function( event ) {
  return event.target;
  }
  
  WebBrowser.prototype.attrName = function( event ) {
  return event.attrName;
  }

  WebBrowser.prototype.testAttrName = function( event , attrName) {
  return event.attrName == attrName;
  }

  WebBrowser.prototype.charCode = function(event) {
     return event.charCode;
  }

  WebBrowser.prototype.calculateOffsetLeft = function( node ) {
  return node.offsetLeft;    
  }
  
  WebBrowser.prototype.calculateOffsetTop = function( node ) {
  return node.offsetTop;    
  }
  
  WebBrowser.prototype.pageX = function( e ) {
    return e.pageX;    
  }
  
  WebBrowser.prototype.pageY = function( e ) {
    return e.pageY;    
  }
  
  WebBrowser.prototype.setNodePosition = function(node,left,top) {
    node.style.left = left+"px";
    node.style.top = top+"px";
  }


} else {

  WebBrowser.prototype.stopPropagation = function( event ) {
    event.cancelBubble = true;
    event.returnValue = false;
    return false;
  }

  WebBrowser.prototype.charCode = function(event) {
    return window.browser.keyCode( event );
  }

  WebBrowser.prototype.target = function( event ) {
    return event.srcElement;
  }

  WebBrowser.prototype.attrName = function( event ) {
  return event.propertyName;
  }
    
  WebBrowser.prototype.testAttrName = function( event , attrName) {
        
        var str = attrName;
        
        if( attrName.indexOf("aria-") >=0 ) {
            str = attrName.replace(/aria-/,"");
            var node = document.getElementById('test1');
            if( node )
               node.innerHTML = str.substr(0,1).toUpperCase();
            var len  = str.length;
            str = "aria" + str.substr(0,1).toUpperCase() + str.substr(1, len);
            var node = document.getElementById('test2');
//            if( node )
//               node.innerHTML = node.innerHTML + "<li>" + str + "</li>";
        }
        
        return event.propertyName == str;
  }
    
  WebBrowser.prototype.calculateOffsetLeft = function(node) {
  var offset = 0;
  
  while( node ) {
    offset += node.offsetLeft;
    node = node.offsetParent;
  }
  
  return offset;    
  }
  
  WebBrowser.prototype.calculateOffsetTop = function(node) {
  var offset = 0;
  
  while( node ) {
    offset = offset + node.offsetTop;
    node = node.offsetParent;
  }
  
  return offset;    
  }
  
  WebBrowser.prototype.pageX = function( e ) {
    return e.clientX + (document.documentElement.scrollLeft || document.body.scrollLeft);    
  }
  
  WebBrowser.prototype.pageY = function( e ) {
    return e.clientY + (document.documentElement.scrollTop || document.body.scrollTop);    
  }
  
  WebBrowser.prototype.setNodePosition = function(node,left,top) {
    offsetx = 0;
    offsety = 0;
    nnode = node.offsetParent
    while( nnode ) {
      offsetx = offsetx + nnode.offsetLeft;
      offsety = offsety + nnode.offsetTop;
      nnode = nnode.offsetParent;
    }
    node.style.left = left-offsetx+"px";
    node.style.top = top-offsety+"px";
  }
  
};


if (document.addEventListener) {

     // Functions for W3C Standards compliant implementation of adding event handlers

     WebBrowser.prototype.addEvent = function(elmTarget, sEventName, fCallback) {
       elmTarget.addEventListener(sEventName, fCallback, false);
       returnValue = true;
     };

     WebBrowser.prototype.removeEvent = function(elmTarget, sEventName, fCallback) {
       elmTarget.removeEventListener(sEventName, fCallback, false);
       returnValue = true;
     };

     WebBrowser.prototype.addChangeEvent =  function(elmTarget, fCallback) {
      elmTarget.addEventListener("DOMAttrModified", fCallback, false);
      returnValue = true;
    };

} else {

  if(document.attachEvent) {

     // IE Specific Event handler functions
     WebBrowser.prototype.addEvent = function(elmTarget, sEventName, fCallback) {
       returnValue = elmTarget.attachEvent('on' + sEventName, fCallback);
     };

     WebBrowser.prototype.removeEvent = function(elmTarget, sEventName, fCallback) {
       returnValue = elmTarget.detachEvent('on' + sEventName, fCallback);
     };

    WebBrowser.prototype.addChangeEvent =  function(elmTarget, fCallback) {
      returnValue = elmTarget.attachEvent("onpropertychange", fCallback);
    };

  } else {

     // For browsers that do not support W3C or IE event functions
     WebBrowser.prototype.addEvent = function(elmTarget, sEventName, fCallback) {
       return false;
     };

     WebBrowser.prototype.removeEvent = function(elmTarget, sEventName, fCallback) {
       return false;
     };

     WebBrowser.prototype.addChangeEvent =  function(elmTarget, fCallback) {
       return false;
     };

  }

}

var browser = new WebBrowser();

  </script>

  <script type="text/javascript">
/**
*
* The checkGuess function checks the value of text box for a value between 1 and 10
*
* @contructor
*/

var MAX_NUM = 10;
var MIN_NUM = 1;

function Guess( text_id, check_id, again_id, box_id, alert_id ) {

   this.text_id = text_id;
   this.check_id = check_id;
   this.again_id = again_id;
   this.box_id = box_id;
   this.alert_id = alert_id;
   this.max_num = MAX_NUM;
   this.min_num = MIN_NUM;
   this.value = 1;
}

/**
* init is a subclass of Guess
*  
* @member Guess
*
* @return nothing
*/

Guess.prototype.init = function() {

  this.node_text  = document.getElementById(this.text_id);
  this.node_check = document.getElementById(this.check_id);
  this.node_again = document.getElementById(this.again_id);  
  this.node_box   = document.getElementById(this.box_id);  
  this.node_alert = document.getElementById(this.alert_id);  

  var obj = this;

  newGuessValue( this );  

  browser.addEvent(this.node_text, "keydown", function(event) {handleGuessKeyDownEvent(event, obj ); },   false);
  browser.addEvent(this.node_check, "click", function(event) {handleCheckGuessClickEvent(event, obj ); },   false);
  browser.addEvent(this.node_again, "click", function(event) {handlePlayAgainClickEvent(event,  obj ); },   false);

}

/**
* newGuessValue is a subclass of Guess
*  
* @member Guess
*
* @return nothing
*/

function newGuessValue( guess ) {

  guess.value = Math.floor(Math.random() * (guess.max_num.valueOf() - guess.min_num.valueOf() + 1) ) + guess.min_num.valueOf();
  guess.count = 0;
  guess.node_text.value = "";
  guess.node_text.setAttribute("aria-invalid", "false");
  guess.node_alert.innerHTML = "Make a guess";

}


/**
* handleGuessKeyDownEvent checks the guess and generates alert based on the guess
*
* @param ( event ) event is the event handler for the event
* @param ( Guess object ) guess is the guesss object that is the target of the keyboard event
*
* @return false to stop event propagation if mouse event was used by handler, else true
*/

function handleGuessKeyDownEvent( event, guess ) {
  var e = event || window.event;

  // Check to see if the value is valid

  if( isNaN( guess.node_text.value ) ||  
      (guess.node_text.value.valueOf() < guess.min_num.valueOf() ) ||
      (guess.node_text.value.valueOf() > guess.max_num.valueOf() )  ) {
      guess.node_text.setAttribute("aria-invalid", "true");
  } else {
      guess.node_text.setAttribute("aria-invalid", "false");
  }  // endif

  
  if( e.keyCode == KEY_ENTER )
    handleCheckGuessClickEvent( event, guess );

}

/**
* handleCheckGuessOnClick checks the guess and generates alert based on the guess
*
* @param ( event ) event is the event handler for the event
* @param ( Guess object ) guess is the guesss object that is the target of the keyboard event
*
* @return false to stop event propagation if mouse event was used by handler, else true
*/

function handleCheckGuessClickEvent( event, guess ) {
  
  guess.count++;

  var guess_value = new Number( guess.node_text.value );
  var target_value = new Number( guess.value );
  var guess_count = new Number( guess.count );

  
  if( guess.node_text.value == "" ) {
    guess.node_alert.innerHTML = "You need to enter a value!";
    guess.node_text.select();
    return browser.stopPropagation( event );
  }

  if( isNaN( guess.node_text.value )  ) {
    guess.node_alert.innerHTML =  "'" + guess.node_text.value + "' is not a number.";
    guess.node_text.select();
    return browser.stopPropagation( event );
  }

  if( (guess_value.valueOf() < guess.min_num.valueOf() ) || (guess_value.valueOf() > guess.max_num.valueOf() )  ) {
    guess.node_alert.innerHTML = guess_value + " is not between " + guess.min_num + " and " + guess.max_num;
    guess.node_text.select();
    return browser.stopPropagation( event );
  }

  if( guess_value.valueOf() == target_value.valueOf() ) {

    if( guess_count == 1 )
      guess.node_alert.innerHTML = guess_value + " is right, you got it on your first try!";
    else    
      guess.node_alert.innerHTML = guess_value + " is right, it only took you " + guess_count + " tries!";

  } else {
    
   if( guess_value.valueOf() < target_value.valueOf() ) {
      
           guess.node_alert.innerHTML = guess_value + " is to low, try a higher number.";
           guess.node_text.select();
      
   } else {
      
           guess.node_alert.innerHTML = guess_value + " is to high, try a lower number.";
           guess.node_text.select();
      
   } // endif
         
  } // endif
  

  return browser.stopPropagation( event );

}

/**
* handlePlayAgainOnClick checks the guess and generates alert based on the guess
*
* @param ( event ) event is the event handler for the event
* @param ( Guess object ) guess is the guesss object that is the target of the keyboard event
*
* @return false to stop event propagation if mouse event was used by handler, else true
*/

handlePlayAgainClickEvent = function( event, guess ) {
  
  newGuessValue( guess );
  guess.node_text.focus();
  
}





  </script>

  <style type="text/css">

div.guess {
  border: thick double black;
  padding: 1em;
  width: 65%;
  font-family: Arial, Helvetica, sans-serif;
}

div.guess h2 {
  margin: 0;
  padding: 0;
  text-align: center;
  margin-left: 1em;
  margin-right: 1em;
}

div.guess input {
  font-size: 100%;
}

div.guess p.input {
  margin: 0;
  padding: 0;
  font-size: 150%;
  margin-top: .5em;
  margin-bottom: .5em;
  text-align: center;
  margin-left: 1em;
  margin-right: 1em;
}

div.guess input.button {
  margin: 0;
  padding: 0;
  display: inline;
  padding-left: .5em;
  padding-right: .5em;
  padding-top: .25em;
  padding-bottom: .25em;
}


div.guess p.feedback {
  margin: 0;
  padding: .25em;
  border: 2px solid black;
  text-align: center;
  margin-top: .5em;
  margin-bottom: .5em;
  font-weight: bold;
}
  </style>