Ajax: The Definitive Guide Book Forum http://forums.oreilly.com/index.php Fri, 20 Nov 2009 19:02:56 -0500 120 Ajax: The Definitive Guide Book Forum http://www.oreilly.com/catalog/covers/9780596528386_thumb.gif http://forums.oreilly.com/index.php Essay Service http://forums.oreilly.com/index.php?showtopic=5563 essay service you can fully rely on.]]> Fri, 13 Nov 2009 10:23:31 -0500 http://forums.oreilly.com/index.php?showtopic=5563 Question About Xml -- What Is This Element Or Node? http://forums.oreilly.com/index.php?showtopic=5364
I can parse and display all other data except for the Attachment ones

...
<DropdownList1><![CDATA[value1]]></DropdownList1>
<DropdownList11><![CDATA[value1]]></DropdownList11>
<Attachment1 id_type="object_id"><![CDATA[0984598e800302d6]></Attachment1>
<Attachment1 id_type="object_id"><![CDATA[0984598e800302d9]]></Attachment1>
<Attachment1 id_type="object_id"><![CDATA[0984598e800302dc]]></Attachment1>
</CombinedForm2>

Thanks & this may not appear to be related to AJAX but I'm hoping someone will know.]]> Fri, 25 Sep 2009 11:48:53 -0400 http://forums.oreilly.com/index.php?showtopic=5364 Where To Start? http://forums.oreilly.com/index.php?showtopic=1139
]]> Mon, 09 Feb 2009 23:37:02 -0500 http://forums.oreilly.com/index.php?showtopic=1139 Chat Server - Chapter 20 / Page 686 http://forums.oreilly.com/index.php?showtopic=1122
I would apprecite if someone could provide the script that is used to create teh tables behind the Chat Server example.

Thanks,]]> Sat, 07 Feb 2009 11:44:11 -0500 http://forums.oreilly.com/index.php?showtopic=1122 Erase Drawing http://forums.oreilly.com/index.php?showtopic=1075 Mon, 26 Jan 2009 10:54:08 -0500 http://forums.oreilly.com/index.php?showtopic=1075 Tooltip Example 10.6 http://forums.oreilly.com/index.php?showtopic=967 Tooltip example 10-6

I have been struggling with this example. I have not yet implemented the Ajax functionality, though the tooltip does not seem to position in FF and Safari. Making an adjustment in the function positionToolTip by adding the pixel unit does the trick.

return({
top: tipTop+"px",
left: tipLeft+"px",
});

I know it is minor, but imperative for this code to work cross-browser. wink.gif
And while I am at it to complete the code, the tooltip functionality should be evoked while loading the document. It is mentioned in the comments of the code, but hey .. why not paste the code here. Place this at the beginning.

if(window.addEventListener) window.addEventListener('load', loadToolTips, false);
else attachEvent('onload', loadToolTips);
]]> Thu, 08 Jan 2009 15:01:09 -0500 http://forums.oreilly.com/index.php?showtopic=967 Whiteboard Example http://forums.oreilly.com/index.php?showtopic=873 (marked in Red), but fail to see the fault. Even after emptying the first function and leaving the shell it still errors. I have found similar functions on the internet and see no obvious error. I am working off of a Linux Server and accessing the internet with Internet Explorer 7.

I am hoping this section could start a discussion on the complete section Whiteboard and Chat. I will even donate an example page with the work in progress as long as it is not abused.

Below is the code for the first section as taken from the book based on how I understood the instructions. I retained the remark statements for ease of reading. Since you did not say where to add Walter Zorn's code I added the link inside the Wrapper.

You can see the WEB page in action (or not in action) at

Example in Operation

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns-"http://www.w3.org/1999/xhtml" xml:lang-"en">
<html>
<head>

<title>Whiteboard Example</title>
</head>
<body>
<div id=bodyWrapper>
<!--All content goes here -->
/* Path has been modified to protect WEB site */
<script type="text/javascript" src="http://XXX/XXX/ws_jsgraphics.js"> </script>
<script language=JavaScript>
<!--
/**
* This variable, POINT_SIZE , is the size of the pen drawing on the canvas
*/
var POINT_SIZE = 1;
/**
* This variable, POINT_COLOR, is the color of the pen drawing on the canvas.
*/
var POINT_COLOR = '#f00';
/**
* this variable, whiteboard, will be the instatntiation of the jsGraphics class.
*/
var whiteBoard = null;
/* Do all this when the page is done loading... */
Event.observe(window, 'load', function() {
/* Create a new canvas to use for the whiteboard */
whiteBoard = new jsGraphics('whiteBoard');
/* Set the initial color of the pen */
whiteBoard.setColor(POINT_COLOR);
/* Set the initial size of the pen */
whiteBoard.setStroke(POINT_SIZE);
/* Set up events to trap mouse events that occur on the /whiteBoard/ */
Event.observe('whiteBoard', 'mousedown', StartDrawing);
Event.observe('whiteBoard', 'mouseup', StopDrawing);
});

/**
* this function, StartDrawing, is called whenever there is a /mousedown/
* event on the whiteboard, and astarts drawin on the canvas.
*
* @param {object} e The current trapped event.
*/
function StartDrawing(e){
/* did the event actually happen on the whiteboard? */
if(Event.element(e).id == 'whiteBoard')
DrawPoint(Event.pointerX(e), Event.pointerY(e));
Event.observe('whiteBoard', 'mousemove', ContinueDrawing);
}
/**
* This function, StopDrawing, is called whenever there is a /mouseup/
* event on the Whiteboard, and stops all drawing on the canvas.
*
* @param {object} e The current trapped event.
*/

function StopDrawing(e){
/* Stop observin /mousmove/ on the board and reest the last coordinates */
Event.stopObserving('whiteBoard', 'mousemove', ContinueDrawing);
lastPointx = -1;
lastPointY = -1;
}

/**
* This function, Continue Drawing is called as long as there is a
* /mouse/ event on the whiteboard, and draws on the canvas.
*
* @param {object} e The curretn trapped event.
*/
function ContinueDrawing(e){
/* did the event actually happen on the whiteboard? */
if(Event.element(e).id == 'whiteBoard')
DrawPoint(Event.pointerX(e), Event.pointerY(e));
}

/**
** This variable, X_OFFSET, is to act as the constant x-offset value of the
* whiteboard.
*/
var X_OFFSET = 10;
/**
** This variable, Y_OFFSET, is to act as the constant Y-offset value of the
* whiteboard.
*/
var Y_OFFSET = 10;
/**
** This variable, lastPointX, holds the last mouse event X-coordinate on the
* whiteboard.
*/
var lastPointX = -1;
/**
** This variable, lastPointY, holds the last mouse event Y-coordinate on the
* whiteboard.
*/
var lastPointY = -1;

/**
* This function, DrwaPoint, draws the lines on the wiiteboard as the mouse
* interaccts with it. It takes into consideration all offsets for canvas
* postion, and sets the last coordinates for the next line.
*
*@param {Integer} p_x The x-coordinate of the mouse event.
*@param {Integer} p_y The y-coordinate of the mouse event.
*/
function DrawPoint(p_x, p_y){
/* Take offsets into consideration */
p_x = p_x - (X_OFFSET + POINT_SIZE)
p_y = p_y - (Y_OFFSET + POINT_SIZE)
/* Is this the begining of a new drawin sequence? */
If(lastPointX == -1 || lastPointY == -1){
lastPointX = p_x;
lastPointy = p_y;
}

/* Draw the line */
whiteBoard.drawLine(p_x, p_y, lastPointX, lastPointY);
/* Display the line */
whiteBoard.paint();
/* Set the last coordinates to the curretn coordinates */
lastPointX = p_x;
lastPointY = p_y;
}
//-->
</script>
<div id='whiteBoard'></div
</div>
</body>
</html>

Looking forward to an interesting discussion on this intriguing topic.]]> Thu, 18 Dec 2008 11:33:22 -0500 http://forums.oreilly.com/index.php?showtopic=873 Example 7.9 Not Working http://forums.oreilly.com/index.php?showtopic=856
Here's what happens with the code.

* It does nothing in firefox. No hiding of the desired element. Nothing happens.
* In ie sometimes it does nothing and other times it pretends to hide the DIV: parts of the DIV doesn't show on load of the page but when you scroll the page it appears, and the rest of the DIV still is not hidden as should be.
* In ie it always shows an error: "Effect" is undefined. I tried online to see if I could find the problem and its solution to no avail.

- WHAT ORDER SHOULD THE SCRIPTS BE PLACED? I DID EXACTLY AS THE BOOK INSTRUCTS WITH NO RESULT.]]> Sat, 13 Dec 2008 16:44:02 -0500 http://forums.oreilly.com/index.php?showtopic=856 Chapter 4 http://forums.oreilly.com/index.php?showtopic=794
I want to first look at Example 4-1, which shows how to create an XHR object. If I was really thinking about it when I first wrote this chapter, I would have shortened the name of the function to say, CreateXHR, instead of the terribly long createXMLHttpRequest. The following shows the changes I would make to tighten this code, and make the variable names clearer:
CODE
/* Example 4-1, Creating the XMLHttpRequest object. */

/**
* This function, CreateXHR, checks to see what object the browser supports
* in order to create the correct XMLHttpRequest object type (XHR or ActiveX).
*
* @return Returns an XMLHttpRequest object, or null if one cannot be created.
* @type Object
*/
function CreateXHR() {
var retval = null;

if (window.XMLHttpRequest && typeof XMLHttpRequest != 'undefined') {
try {
retval = new XMLHttpRequest();
} catch (ex) {
retval = null;
}
} else if (window.ActiveXObject) {
try {
retval = new ActiveXObject('Msxml2.XMLHTTP');
} catch (ex) {
try {
retval = new ActiveXObject('Microsoft.XMLHTTP');
} catch (ex2) {
retval = null;
}
}
}
return retval;
}


I welcome comments and suggestions. More on this chapter to come.]]> Mon, 01 Dec 2008 16:43:17 -0500 http://forums.oreilly.com/index.php?showtopic=794 Welcome http://forums.oreilly.com/index.php?showtopic=691 Ajax: The Definitive Guide book forum! I hope that this will be a place to explore the examples from the book and expand and improve upon them. I also hope this will be a place where we can help each other with our personal Ajax projects.

If you have questions about Ajax, this is a great place to ask them!

Anthony Holdener (author)
]]> Thu, 30 Oct 2008 01:11:57 -0400 http://forums.oreilly.com/index.php?showtopic=691