/* picsi.js
from pics Feb2005
This version creates a more sophisticated window with optional caption
and makes every effort to size the window correctly.
BJM Dec2004
function to generate a new window of optimal size and display a picture
If the window has already been opened it is just re-positioned since there is no point
in opening more than one. If its open but minimised it will be un-minimised.
N.B. File name is used to create window name so must not have spaces or - chars
or any other strange symbols that might upset javascript or browser. ( Underscore is fine )
Pictures which are larger than the display size are supported by allowing scrollbars
Unfortunately latest security stuff doesn't allow them to be switched on and off
after the image size is known so they have to be allowd for in window sizing
( IE always shows vert scroll even if not needed )
When image download is slow sizing may be unreliable. It is not easy to wait
for completion of download because some browsers do not multi-thread so neither looping nor
interupt based methods work consistently( e.g. onLoad). Status flags such as image.complete
are also inconsistent between browsers.
*/
var win ;
var bestHeight = 0 ;
var bestWidth = 0 ;
var theUrl ;
var picImage = new Image() ;
var caption = " " ;
var hascap = false ;
var wname = " ";
var cappos ="92%";
function imgWindow( url , capst) // main function to call from html
{
theurl = url ;
picImage.src = url ; // start downloading we hope !
picImage.onload = null; // if set here it runs immediately
var cntr = 0;
wname = String ( urlName(theurl) ) ; // name used to ensure uniqueness of window
//alert( "wname is "+wname);
if ( arguments.length > 1 )
{ caption = String(capst) ; hascap = true ;}
else { caption = " " ; hascap = false ;} // blank caption strings overwrites loading message
// although picture should also hide it
// open/create the window
win = window.open("",wname,
"dependent=yes,resizable=yes,hotkeys=no,personalbar=no,scrollbars=yes,status=no" ) ;
// N.B. scrollbars yes - change to no if you prefer then make size allowances smaller below
// alert("window created");
picImage.onload = wsizer ; // nb Mozilla/Firefox tries to run this at once
if ( win.document.images.length > 0 ) //does it exist already ?
{
// alert( win.name + "already exists location = "+ win.location );
win.focus() ; // effectively bring to front
if ( win.closed ) win.open();
}
else // need content for new window
{
var topmarg = 4 ;
if ( hascap ) topmarg = 44 ; // allowance for caption
win.document.open() ;
if ( hascap) win.document.write(""+caption+"
") ;
win.document.write(""
+"loading image ...
") ;
win.document.write("") ;
win.document.close();
wsizer() ;
}
win.moveTo(5,5) ;
return ;
}
function urlName(urln)
{
parts = urln.split("/") ;
if ( parts.length > 0 )
{
fnames = parts[ parts.length-1 ].split(".") ;
if ( fnames.length > 0 ) return fnames[0] ;
}
else return "noname" ;
}
// the following function is used both directly and by the image.onload event trigger
// Since the trigger often runs when it shouldn't ( according to documentation )
// lots of do nothing traps are required to prevent errors when the window is undefined
// Mozilla also applies resize to all windows so the name check is vital.
function wsizer(ev) // resize image window
{
// alert("called wsizer") ;
if ( win == undefined ) return ; // Mozilla fail trap
if ( win.closed ) return; // IE fail trap
if ( win.document == undefined ) return ; // ditto
if (win.name != wname ) return ; //ditto
var capheight = 0;
if ( hascap ) capheight = 40 ;
var plusx = 80 ; // width allowance for scroll bar etc.
var plusy = 110 ; // height allowance for window title status bar etc.
bestHeight = picImage.height ; // get image size
bestWidth = picImage.width ;
if ( bestHeight > 10 && bestWidth > 10 ) // 11 X 11 is minimum picture size allowed
{
var scalex = 1.0 ;
var scaley = 1.0 ;
// decide if window needs scaling to fit screen
if( ( bestWidth + plusx ) > screen.width ) // needs horizontal scrolling
{
scalex = screen.width / (bestWidth + plusx) ;
plusy = plusy + 30 ; // extra pixels for scroll bar
}
if ( ( bestHeight + plusy + capheight ) > screen.height )
{
scaley = screen.height / ( bestHeight + plusy + capheight ) ;
}
bestHeight = bestHeight * scaley - 20 ; // scales window to fit screen
bestWidth = bestWidth * scalex - 20 ; // not image!!
}
else // use 1/4 screen if you dont know the picture size
{
bestHeight = screen.Height/ 2 ;
bestWidth = screen.Width / 2 ;
}
win.focus() ; // if you don't do this ie wont resize after deminimizing
win.resizeTo(bestWidth + plusx, bestHeight + plusy + capheight ); // set size
// win.status="status caption" ; could put title in status area
return ;
}
function nref(){} // this empty function is to allow a dummy href of
// the form href="javascript:nref()" cos
// css :hover won't work unless an anchor contains an href attribute
// alternative is to use href="javascript:imgWindow(url,caption)"