JavaScript DHTML/YUI Library/Event

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Implementing Container Keyboard Shortcuts with KeyListener

   <source lang="html4strict">


<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <html> <head> 

   <meta http-equiv="content-type" content="text/html; charset=utf-8">

<title>Implementing Container Keyboard Shortcuts with KeyListener</title> <style type="text/css"> /*margin and padding on body element 

 can introduce errors in determining
 element position and are not recommended;
 we turn them off as a foundation for YUI
 CSS treatments. */

body { 

 margin:0;
 padding:0;

} </style> <link rel="stylesheet" type="text/css" href="yui_2.7.0b-lib/fonts/fonts-min.css" /> <link rel="stylesheet" type="text/css" href="yui_2.7.0b-lib/container/assets/skins/sam/container.css" /> <script type="text/javascript" src="yui_2.7.0b-lib/yahoo-dom-event/yahoo-dom-event.js"></script> <script type="text/javascript" src="yui_2.7.0b-lib/dragdrop/dragdrop-min.js"></script> <script type="text/javascript" src="yui_2.7.0b-lib/container/container-min.js"></script>

</head> <body class=" yui-skin-sam">

Implementing Container Keyboard Shortcuts with KeyListener

The KeyListener class integrates with the Container family allowing you to specify specific keys or key combinations to show and hide your containers.

<style> 

 #example {height:20em;}

</style> <script> YAHOO.namespace("example.container"); function init() { 

 // Build panel1 based on markup
 YAHOO.example.container.panel1 = new YAHOO.widget.Panel("panel1", { xy:[350,330], width:"250px", visible: false } );
 
 var kl = new YAHOO.util.KeyListener(document, { keys:27 },                
                         { fn:YAHOO.example.container.panel1.hide,
                         scope:YAHOO.example.container.panel1,
                         correctScope:true }, "keyup" ); 
                         // keyup is used here because Safari won"t recognize the ESC
                         // keydown event, which would normally be used by default
 YAHOO.example.container.panel1.cfg.queueProperty("keylisteners", kl);
 YAHOO.example.container.panel1.render();
 var kl2 = new YAHOO.util.KeyListener(document, { ctrl:true, keys:89 }, 
                          { fn:YAHOO.example.container.panel1.show, 
                          scope:YAHOO.example.container.panel1,
                          correctScope:true } );
 
 kl2.enable();
 YAHOO.util.Event.addListener("show", "click", YAHOO.example.container.panel1.show, YAHOO.example.container.panel1, true);
 YAHOO.util.Event.addListener("hide", "click", YAHOO.example.container.panel1.hide, YAHOO.example.container.panel1, true);

} YAHOO.util.Event.onDOMReady(init); </script>

panel1: <button id="show">Show (Ctrl+Y)</button> <button id="hide">Hide (Esc)</button>

</body> </html> 


 </source>

<A href="http://www.wbex.ru/Code/JavaScriptDownload/yui_2.7.0b.zip">yui_2.7.0b.zip( 4,431 k)</a>


Simple Event Handling and Processing

   <source lang="html4strict">

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <html> <head> 

   <meta http-equiv="content-type" content="text/html; charset=utf-8">

<title>Simple Event Handling and Processing</title> <style type="text/css"> /*margin and padding on body element 

 can introduce errors in determining
 element position and are not recommended;
 we turn them off as a foundation for YUI
 CSS treatments. */

body { 

 margin:0;
 padding:0;

} </style> <link rel="stylesheet" type="text/css" href="yui_2.7.0b-lib/fonts/fonts-min.css" /> <script type="text/javascript" src="yui_2.7.0b-lib/yahoo-dom-event/yahoo-dom-event.js"></script>

</head> <body class=" yui-skin-sam">

Simple Event Handling and Processing

Clicking in the blue box will pop up a "Hello World!" alert window. Clicking on the first link will take you to the YUI website; clicking on the second link, which has the same href attribute, will pop up an alert instead and not navigate to a new page.

Event Utility is used here to do two things:

  1. Attach the click event handler to the blue box;
  2. Attach an event handler to the second <a> element that uses YAHOO.util.Event.preventDefault() to prevent the link, when clicked, from navigating to a new page.

<script> (function() {

//A function that pops up a "Hello World" alert: var helloWorld = function(e) { 

 YAHOO.log("helloWorld function firing.", "info", "example");
 alert("Hello World!");

} //subscribe the helloWorld function as an event //handler for the click event on the container //div: YAHOO.util.Event.addListener("container", "click", helloWorld); //A function that pops up an alert and //prevents the default behavior of the event //for which it is a handler: var interceptLink = function(e) { 

 YAHOO.util.Event.preventDefault(e);
 YAHOO.log("You clicked on the second YUI link.", "info", "example");
 alert("You clicked on the second YUI link.");

} //subscribe our interceptLink function //as a click handler for the second anchor //element: YAHOO.util.Event.addListener("secondA", "click", interceptLink); //log message to indicate that the example is ready: YAHOO.log("When you begin interacting with the example at left, you"ll see log messages appear here.", "info", "example"); })(); </script> <style>

  1. container {background-color:#00CCFF; border:1px dotted black; padding:1em; cursor:pointer;}

</style>

Click for Hello World alert.

<a href="http://developer.yahoo.ru/yui" id="firstA">The YUI Library. (Link navigates away from page.)</a>

<a href="http://developer.yahoo.ru/yui" id="secondA">The YUI Library. (Link"s default behavior is suppressed.)</a>

</body> </html> 


 </source>

<A href="http://www.wbex.ru/Code/JavaScriptDownload/yui_2.7.0b.zip">yui_2.7.0b.zip( 4,431 k)</a>


Using Custom Events

   <source lang="html4strict">


<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <html> <head> 

   <meta http-equiv="content-type" content="text/html; charset=utf-8">

<title>Using Custom Events</title> <style type="text/css"> /*margin and padding on body element 

 can introduce errors in determining
 element position and are not recommended;
 we turn them off as a foundation for YUI
 CSS treatments. */

body { 

 margin:0;
 padding:0;

} </style> <link rel="stylesheet" type="text/css" href="yui_2.7.0b-lib/fonts/fonts-min.css" /> <script type="text/javascript" src="yui_2.7.0b-lib/yahoo-dom-event/yahoo-dom-event.js"></script>


<style type="text/css">

  1. container {width:400px; height:100px; padding:10px; border:1px dotted black;background-color:#CCCCCC; cursor:pointer;}
  2. resizer {width:200px; height:75px; background-color:#00CCFF;}
  3. subscriberWidth {width:200px; height:75px; margin-top:10px;background-color:#CC9966;}
  4. subscriberHeight {width:200px; height:75px; margin-top:10px;background-color:#FF3333;}

</style>


</head> <body class=" yui-skin-sam">

Using Custom Events

Clicking in the grey box resizes the blue <div> within it. We consider this an "interesting moment" in our script, so we create a <a href="/yui/event/#customevent">Custom Event</a> called onSizeChange that fires whenever the blue box is resized. This Custom Event, when fired, publishes the blue box"s new size. Note: onSizeChange isn"t a DOM event — it"s an arbitrary "custom" event that has meaning in the context of our script, and an event that we think other scripts on the page might be interested in knowing about.

One subscriber to our onSizeChange Custom Event looks at the new width and resizes the brown box to match. A second subscriber looks at the blue <div>"s new height and resizes the red box to match. 

   Click anywhere within the grey box 
 to resize me.

 Width will resize to match blue 
 box.

 Height will resize to match blue
 box.

<script> (function() { 

 //create a new custom event, to be fired
 //when the resizer div"s size is changed
 var onSizeChange = new YAHOO.util.CustomEvent("onSizeChange");
 
 //get local references to dom elements,
 //for convenience
 var container = YAHOO.util.Dom.get("container");
 var resizer = YAHOO.util.Dom.get("resizer");
 
 //when the container is clicked on, change the 
 //dimensions of the resizer -- as long as it appears
 //to be a valid new size (>0 width, >12 height).
 function fnClick(e){
   
   //0,0 point is the top left corner of the container,
   //minus its padding:
   var containerX = YAHOO.util.Dom.getX("container");
   var containerY = YAHOO.util.Dom.getY("container");
   var clickX = YAHOO.util.Event.getPageX(e);
   var clickY = YAHOO.util.Event.getPageY(e);
   //get container padding using Dom"s getStyle():
   var containerPaddingX = parseInt(YAHOO.util.Dom.getStyle("container","padding-left"), 10);
   var containerPaddingY = parseInt(YAHOO.util.Dom.getStyle("container","padding-top"), 10);
   var newWidth = clickX - containerX - containerPaddingX;
   var newHeight = clickY - containerY - containerPaddingY;
   
   //if there is a valid new dimension, we"ll change
   //resizer and fire our custom event
   if ((newWidth > 0)||(newHeight > 12)) {
     //correct new height/width to guarantee
     //minimum of 0x12  
     if (newWidth < 0) {newWidth = 1;}
     if (newHeight < 12) {newHeight = 12;}
     //show new dimensions in resizer:
     YAHOO.util.Dom.get("resizer").innerHTML = "New size: " + newWidth + "x" + newHeight;
     //change the dimensions of resizer, using
     //Dom"s setStyle:
     YAHOO.util.Dom.setStyle("resizer", "width", newWidth + "px");
     YAHOO.util.Dom.setStyle("resizer", "height", newHeight + "px");
      //fire the custom event, passing
      //the new dimensions in as an argument;
      //our subscribers will be able to use this
      //information:
     onSizeChange.fire({width: newWidth, height: newHeight});
   };
   
 }
 
 //listen for clicks on the container
 YAHOO.util.Event.addListener("container", "click", fnClick);
 //a handler to respond to the custom event that
 //we"re firing when the resizer changes size; we"ll
 //resize its width to match the resizer.
 fnSubscriberWidth = function(type, args) {
   var elWidth = YAHOO.util.Dom.get("subscriberWidth");
   var newWidth = args[0].width;
   YAHOO.util.Dom.setStyle(elWidth, "width", (newWidth + "px"));
   elWidth.innerHTML = ("My new width: " + newWidth + "px");
   YAHOO.log("The Custom Event fired; the the new width is " + newWidth + "px.", "info", "example");
 }
 
 //another handler to respond to the custom event that
 //we"re firing when the resizer changes size; this
 //one cares about the height of the resizer.
 fnSubscriberHeight = function(type, args) {
   var elHeight = YAHOO.util.Dom.get("subscriberHeight");
   var newHeight = args[0].height;
   YAHOO.util.Dom.setStyle(elHeight, "height", (newHeight + "px"));
   elHeight.innerHTML = ("My new height: " + newHeight + "px");
   YAHOO.log("The Custom Event fired; the the new height is " + newHeight + "px.", "info", "example");
 }  
 
 //all that remains is to subscribe our
 //handlers to the onSizeChange custom event:
 onSizeChange.subscribe(fnSubscriberWidth);
 onSizeChange.subscribe(fnSubscriberHeight);
 
 
 YAHOO.log("The example has finished loading; as you interact with it, you"ll see log messages appearing here.", "info", "example");

})(); </script>

</body> </html> 


 </source>

<A href="http://www.wbex.ru/Code/JavaScriptDownload/yui_2.7.0b.zip">yui_2.7.0b.zip( 4,431 k)</a>

Источник — «http://wbex.ru/index.php?title=JavaScript_DHTML/YUI_Library/Event&oldid=3993»