lib/overlib/overlib_followscroll.js

   1 //\/////
   2 //\  overLIB Follow Scroll Plugin
   3 //\  This file requires overLIB 4.10 or later.
   4 //\
   5 //\  overLIB 4.10 - You may not remove or change this notice.
   6 //\  Copyright Erik Bosrup 1998-2004. All rights reserved.
   7 //\  Contributors are listed on the homepage.
   8 //\  See http://www.bosrup.com/web/overlib/ for details.
   9 //   $Revision$                      $Date$
  10 //\/////
  11 //\mini
  12
  13 ////////
  14 // PRE-INIT
  15 // Ignore these lines, configuration is below.
  16 ////////
  17 if (typeof olInfo == 'undefined' || typeof olInfo.meets == 'undefined' || !olInfo.meets(4.10)) alert('overLIB 4.10 or later is required for the Follow Scroll Plugin.');
  18 else {
  19 registerCommands('followscroll,followscrollrefresh');
  20
  21
  22 ////////
  23 // DEFAULT CONFIGURATION
  24 // You don't have to change anything here if you don't want to. All of this can be
  25 // changed on your html page or through an overLIB call.
  26 ////////
  27 // Default value for scroll is not to scroll (0)
  28 if (typeof ol_followscroll=='undefined') var ol_followscroll=0;
  29 if (typeof ol_followscrollrefresh=='undefined') var ol_followscrollrefresh=100;
  30
  31 ////////
  32 // END OF CONFIGURATION
  33 // Don't change anything below this line, all configuration is above.
  34 ////////
  35
  36
  37
  38
  39
  40
  41
  42 ////////
  43 // INIT
  44 ////////
  45 // Runtime variables init. Don't change for config!
  46 var o3_followscroll=0;
  47 var o3_followscrollrefresh=100;
  48
  49
  50 ////////
  51 // PLUGIN FUNCTIONS
  52 ////////
  53 function setScrollVariables() {
  54         o3_followscroll=ol_followscroll;
  55         o3_followscrollrefresh=ol_followscrollrefresh;
  56 }
  57
  58 // Parses Shadow and Scroll commands
  59 function parseScrollExtras(pf,i,ar) {
  60         var k=i,v;
  61         if (k < ar.length) {
  62                 if (ar[k]==FOLLOWSCROLL) { eval(pf +'followscroll=('+pf+'followscroll==0) ? 1 : 0'); return k; }
  63                 if (ar[k]==FOLLOWSCROLLREFRESH) { eval(pf+'followscrollrefresh='+ar[++k]); return k; }
  64         }
  65         return -1;
  66 }
  67
  68
  69
  70 // Function to support scroll feature (overloads default)
  71 function scroll_placeLayer() {
  72         var placeX, placeY, widthFix = 0;
  73
  74         // HORIZONTAL PLACEMENT
  75         if (o3_frame.innerWidth) {
  76                 widthFix=Math.ceil(1.2*(o3_frame.outerWidth - o3_frame.innerWidth));
  77     widthFix = (widthFix > 50) ? 20 : widthFix;
  78                 iwidth=o3_frame.innerWidth;
  79         } else if (eval('o3_frame.'+docRoot)&&eval("typeof o3_frame."+docRoot+".clientWidth=='number'")&&eval('o3_frame.'+docRoot+'.clientWidth'))
  80                 iwidth=eval('o3_frame.'+docRoot+'.clientWidth');
  81
  82         // Horizontal scroll offset
  83         winoffset=(olIe4) ? eval('o3_frame.'+docRoot+'.scrollLeft') : o3_frame.pageXOffset;
  84
  85         placeX = runHook('horizontalPlacement',FCHAIN,iwidth,winoffset,widthFix);
  86
  87         // VERTICAL PLACEMENT
  88         if (o3_frame.innerHeight) iheight=o3_frame.innerHeight;
  89         else if (eval('o3_frame.'+docRoot)&&eval("typeof o3_frame."+docRoot+".clientHeight=='number'")&&eval('o3_frame.'+docRoot+'.clientHeight'))
  90                 iheight=eval('o3_frame.'+docRoot+'.clientHeight');
  91
  92         // Vertical scroll offset
  93         scrolloffset=(olIe4) ? eval('o3_frame.'+docRoot+'.scrollTop') : o3_frame.pageYOffset;
  94
  95         placeY = runHook('verticalPlacement',FCHAIN,iheight,scrolloffset);
  96
  97         // Actually move the object.
  98         repositionTo(over,placeX,placeY);
  99
 100         if (o3_followscroll && o3_sticky && (o3_relx || o3_rely) && (typeof o3_draggable == 'undefined' || !o3_draggable)) {
 101                 if (typeof over.scroller=='undefined' || over.scroller.canScroll) over.scroller = new Scroller(placeX-winoffset,placeY-scrolloffset,o3_followscrollrefresh);
 102         }
 103 }
 104
 105
 106
 107 ///////
 108 // SUPPORT ROUTINES FOR SCROLL FEATURE
 109 ///////
 110
 111 // Scroller constructor
 112 function Scroller(X,Y,refresh) {
 113         this.canScroll=0;
 114         this.refresh=refresh;
 115         this.x=X;
 116         this.y=Y;
 117         this.timer=setTimeout("repositionOver()",this.refresh);
 118 }
 119
 120 // Removes the timer to stop replacing the layer.
 121 function cancelScroll() {
 122         if (!o3_followscroll || typeof over.scroller == 'undefined') return;
 123         over.scroller.canScroll = 1;
 124
 125         if (over.scroller.timer) {
 126                 clearTimeout(over.scroller.timer);
 127                 over.scroller.timer=null;
 128         }
 129 }
 130
 131 // Find out how much we've scrolled.
 132         function getPageScrollY() {
 133         if (o3_frame.pageYOffset) return o3_frame.pageYOffset;
 134         if (eval(docRoot)) return eval('o3_frame.' + docRoot + '.scrollTop');
 135         return -1;
 136 }
 137 function getPageScrollX() {
 138         if (o3_frame.pageXOffset) return o3_frame.pageXOffset;
 139         if (eval(docRoot)) return eval('o3_frame.'+docRoot+'.scrollLeft');
 140         return -1;
 141 }
 142
 143 // Find out where our layer is
 144 function getLayerTop(layer) {
 145         if (layer.pageY) return layer.pageY;
 146         if (layer.style.top) return parseInt(layer.style.top);
 147         return -1;
 148 }
 149 function getLayerLeft(layer) {
 150         if (layer.pageX) return layer.pageX;
 151         if (layer.style.left) return parseInt(layer.style.left);
 152         return -1;
 153 }
 154
 155 // Repositions the layer if needed
 156 function repositionOver() {
 157         var X, Y, pgLeft, pgTop;
 158         pgTop = getPageScrollY();
 159         pgLeft = getPageScrollX();
 160         X = getLayerLeft(over)-pgLeft;
 161         Y = getLayerTop(over)-pgTop;
 162
 163         if (X != over.scroller.x || Y != over.scroller.y) repositionTo(over, pgLeft+over.scroller.x, pgTop+over.scroller.y);
 164         over.scroller.timer = setTimeout("repositionOver()", over.scroller.refresh);
 165 }
 166
 167 ////////
 168 // PLUGIN REGISTRATIONS
 169 ////////
 170 registerRunTimeFunction(setScrollVariables);
 171 registerCmdLineFunction(parseScrollExtras);
 172 registerHook("hideObject",cancelScroll,FAFTER);
 173 registerHook("placeLayer",scroll_placeLayer,FREPLACE);
 174 if (olInfo.meets(4.10)) registerNoParameterCommands('followscroll');
 175 }