website/inc/position.js

   1 // position.js: make edge-positioning work on IE/Win
   2 // version 0.5, 15-Jul-2003
   3 // written by Andrew Clover <and@doxdesk.com>, use freely
   4
   5 /*@cc_on
   6 @if (@_win32 && @_jscript_version>4)
   7
   8 var position_h= new Array();
   9 var position_v= new Array();
  10 var position_viewport;
  11 var position_width= 0;
  12 var position_height= 0;
  13 var position_fontsize= 0;
  14 var position_ARBITRARY= 200;
  15
  16 // Binding. Called on each new element; if the it's <body>, initialise script.
  17 // Check all new elements to see if they need our help, make lists of them
  18
  19 function position_bind(el) {
  20   if (!position_viewport) {
  21     if (!document.body) return;
  22     // initialisation
  23     position_viewport= (document.compatMode=='CSS1Compat') ?
  24       document.documentElement : document.body;
  25     window.attachEvent('onresize', position_delayout);
  26     var em= document.createElement('div');
  27     em.setAttribute('id', 'position_em');
  28     em.style.position= 'absolute'; em.style.visibility= 'hidden';
  29     em.style.fontSize= 'xx-large'; em.style.height= '5em';
  30     em.style.top='-5em'; em.style.left= '0';
  31     em.style.setExpression('width', 'position_checkFont()');
  32     document.body.appendChild(em);
  33   }
  34
  35   // check for absolute edge-positioned elements (ignore ones from fixed.js!)
  36   var st= el.style; var cs= el.currentStyle;
  37   if (cs.position=='absolute' && !st.fixedPWidth) {
  38     if (cs.left!='auto' && cs.right!='auto') {
  39       position_h[position_h.length]= el;
  40       st.position_width= position_ARBITRARY;
  41       st.width= st.position_width+'px';
  42       position_delayout();
  43     }
  44     if (cs.top!='auto' && cs.bottom!='auto') {
  45       position_v[position_v.length]= el;
  46       st.position_height= position_ARBITRARY;
  47       st.height= st.position_height+'px';
  48       position_delayout();
  49   } }
  50 }
  51
  52 function position_checkFont() { position_delayout(); return '1em'; }
  53
  54 // Layout. For each edge-positioned axis, measure difference between min-edge
  55 // and max-edge positioning, set size to the difference
  56
  57 // Request re-layout at next available moment
  58 var position_delaying= false;
  59 function position_delayout() {
  60   if (position_delaying) return;
  61   position_delaying= true;
  62   window.setTimeout(position_layout, 0);
  63 }
  64
  65 function position_layout() {
  66   position_delaying= false;
  67   var i, el, st, pos, tmp;
  68   var fs= document.all['position_em'].offsetWidth;
  69   var newfs= (position_fontsize!=fs && position_fontsize!=0);
  70   position_fontsize= fs;
  71
  72   // horizontal axis
  73   if (position_viewport.clientWidth!=position_width || newfs) {
  74     position_width= position_viewport.clientWidth;
  75     for (i= position_h.length; i-->0;) {
  76       el= position_h[i]; st= el.style; cs= el.currentStyle;
  77       pos= el.offsetLeft; tmp= cs.left; st.left= 'auto';
  78       st.position_width+= el.offsetLeft-pos; st.left= tmp;
  79       if (st.position_width<1) st.position_width= 1;
  80       st.width= st.position_width+'px';
  81   } }
  82   // vertical axis
  83   if (position_viewport.clientHeight!=position_height || newfs) {
  84     position_height= position_viewport.clientHeight;
  85     for (i= position_v.length; i-->0;) {
  86       el= position_v[i]; st= el.style; cs= el.currentStyle;
  87       pos= el.offsetTop; tmp= cs.top; st.top= 'auto';
  88       st.position_height+= el.offsetTop-pos; st.top= tmp;
  89       if (st.position_height<1) st.position_height= 1;
  90       st.height= st.position_height+'px';
  91   } }
  92 }
  93
  94 // Scanning. Check document every so often until it has finished loading. Do
  95 // nothing until <body> arrives, then call main init. Pass any new elements
  96 // found on each scan to be bound
  97
  98 var position_SCANDELAY= 500;
  99
 100 var position_nscanned= 0;
 101 function position_scan() {
 102   var nall= document.all.length;
 103   for (var i= position_nscanned; i<nall; i++)
 104     position_bind(document.all[i]);
 105   position_nscanned= nall;
 106 }
 107
 108 var position_scanner;
 109 function position_stop() {
 110   window.clearInterval(position_scanner);
 111   position_scan();
 112 }
 113
 114 position_scan();
 115 position_scanner= window.setInterval(position_scan, position_SCANDELAY);
 116 window.attachEvent('onload', position_stop);
 117
 118 @end @*/