JavaScript draggable iframe effect code_javascript skills-JS Tutorial-php.cn

// HISTORY
// ------------------------------------------------------------------
// Jan 23, 2004: Fixed problems which caused the script not to work in
//               some framed situations. Improved browser support.
//               Added easier "addHandle" implentation.
// May 25, 2003: Added better event position detection, added caching
//               of IFRAME object references to avoid lookups. Added
//               'move' cursor to handles.
// May 24, 2003: Updated to fix bug with Netscape 7.x
// May 23, 2003: Created
/*
DESCRIPTION: The purpose of this library is to allow IFRAME objects to be
dragged around the screen in the same way that popup windows or draggable
DIV tags are often used. Since IFRAME objects always cover form objects,
this makes an ideal solution for a simulated "popup window" on a page with
form objects.

COMPATABILITY: Tested successfully with IE 6.x, Netscape 6.2, 7.x, and
Mozilla 1.3. Since this script uses IFRAME objects and DHTML heavily,
cross-browser compatability is a goal but there may be some quirks in
various browser versions.

USAGE:
1) Include the source file in your main document which contains the IFRAME
   tags. Make sure each iframe has a unique "ID" attribute. For best browser
   compatability, also include a "NAME" attribute in the IFRAME tag that
   has the same value as the "ID" attribute.

2) In the document content of each IFRAME which will be draggable, , do two
    things:
    a) Include the dragiframe.js file in the source
    b) add this code to the

tag:
   onLoad="addHandle(document.getElementById('toolbar'), window);"
   Where 'toolbar' is the ID of an element on the page which should be the 'handle'
   by which the IFRAME should be dragged (like a toolbar at the top).
   If you want the IFRAME to be draggable by clicking anywhere in the IFRAME
   document, use:
   onLoad="addHandle(document.getElementsByTagName('body').item(0), window);"

   NOTE: The code will automatically look up the window.parent tree to find a
   parent document with draggable iframes enabled. It will attach itself to the
   first document it finds, allowing it to work within a framed environment.

In your parent document (containing the IFRAMEs), you may set a couple of options:

// Set to true to always bring the selected IFRAME to the "top" of the zIndex.
// Defaults to false
bringSelectedIframeToTop(true|false);

// Set to true to allow IFRAME objects to be dragged off the screen. This may
// make the handle be no longer reachable by the mouse, causing the IFRAME to
// be stranded.
// Defaults to false
allowDragOffScreen(true|false);

// You may manually set this variable to define the highest zIndex used in
// your main document. This is used to determine what zIndex to give an IFRAME
// if it is selected and "bringSelectedIframeToTop" is set to true.
// Defaults to 99.
DIF_highestZIndex=4;

NOTES:
1) If you have defined onmousedown or onmouseup event handlers for your "handle"
   object in the IFRAME, they will be over-written.
2) If you have defined an onmousemove handler in either the main document or
   the IFRAME document, they will be over-written.
3) All