lib/dojo/dnd/autoscroll.js.uncompressed.js

   1 define("dojo/dnd/autoscroll", ["../main", "../window"], function(dojo) {
   2         // module:
   3         //              dojo/dnd/autoscroll
   4         // summary:
   5         //              TODOC
   6
   7 dojo.getObject("dnd", true, dojo);
   8
   9 dojo.dnd.getViewport = dojo.window.getBox;
  10
  11 dojo.dnd.V_TRIGGER_AUTOSCROLL = 32;
  12 dojo.dnd.H_TRIGGER_AUTOSCROLL = 32;
  13
  14 dojo.dnd.V_AUTOSCROLL_VALUE = 16;
  15 dojo.dnd.H_AUTOSCROLL_VALUE = 16;
  16
  17 dojo.dnd.autoScroll = function(e){
  18         // summary:
  19         //              a handler for onmousemove event, which scrolls the window, if
  20         //              necesary
  21         // e: Event
  22         //              onmousemove event
  23
  24         // FIXME: needs more docs!
  25         var v = dojo.window.getBox(), dx = 0, dy = 0;
  26         if(e.clientX < dojo.dnd.H_TRIGGER_AUTOSCROLL){
  27                 dx = -dojo.dnd.H_AUTOSCROLL_VALUE;
  28         }else if(e.clientX > v.w - dojo.dnd.H_TRIGGER_AUTOSCROLL){
  29                 dx = dojo.dnd.H_AUTOSCROLL_VALUE;
  30         }
  31         if(e.clientY < dojo.dnd.V_TRIGGER_AUTOSCROLL){
  32                 dy = -dojo.dnd.V_AUTOSCROLL_VALUE;
  33         }else if(e.clientY > v.h - dojo.dnd.V_TRIGGER_AUTOSCROLL){
  34                 dy = dojo.dnd.V_AUTOSCROLL_VALUE;
  35         }
  36         window.scrollBy(dx, dy);
  37 };
  38
  39 dojo.dnd._validNodes = {"div": 1, "p": 1, "td": 1};
  40 dojo.dnd._validOverflow = {"auto": 1, "scroll": 1};
  41
  42 dojo.dnd.autoScrollNodes = function(e){
  43         // summary:
  44         //              a handler for onmousemove event, which scrolls the first avaialble
  45         //              Dom element, it falls back to dojo.dnd.autoScroll()
  46         // e: Event
  47         //              onmousemove event
  48
  49         // FIXME: needs more docs!
  50
  51         var b, t, w, h, rx, ry, dx = 0, dy = 0, oldLeft, oldTop;
  52
  53         for(var n = e.target; n;){
  54                 if(n.nodeType == 1 && (n.tagName.toLowerCase() in dojo.dnd._validNodes)){
  55                         var s = dojo.getComputedStyle(n),
  56                                 overflow = (s.overflow.toLowerCase() in dojo.dnd._validOverflow),
  57                                 overflowX = (s.overflowX.toLowerCase() in dojo.dnd._validOverflow),
  58                                 overflowY = (s.overflowY.toLowerCase() in dojo.dnd._validOverflow);
  59                         if(overflow || overflowX || overflowY){
  60                                 b = dojo._getContentBox(n, s);
  61                                 t = dojo.position(n, true);
  62                         }
  63                         // overflow-x
  64                         if(overflow || overflowX){
  65                                 w = Math.min(dojo.dnd.H_TRIGGER_AUTOSCROLL, b.w / 2);
  66                                 rx = e.pageX - t.x;
  67                                 if(dojo.isWebKit || dojo.isOpera){
  68                                         // FIXME: this code should not be here, it should be taken into account
  69                                         // either by the event fixing code, or the dojo.position()
  70                                         // FIXME: this code doesn't work on Opera 9.5 Beta
  71                                         rx += dojo.body().scrollLeft;
  72                                 }
  73                                 dx = 0;
  74                                 if(rx > 0 && rx < b.w){
  75                                         if(rx < w){
  76                                                 dx = -w;
  77                                         }else if(rx > b.w - w){
  78                                                 dx = w;
  79                                         }
  80                                         oldLeft = n.scrollLeft;
  81                                         n.scrollLeft = n.scrollLeft + dx;
  82                                 }
  83                         }
  84                         // overflow-y
  85                         if(overflow || overflowY){
  86                                 //console.log(b.l, b.t, t.x, t.y, n.scrollLeft, n.scrollTop);
  87                                 h = Math.min(dojo.dnd.V_TRIGGER_AUTOSCROLL, b.h / 2);
  88                                 ry = e.pageY - t.y;
  89                                 if(dojo.isWebKit || dojo.isOpera){
  90                                         // FIXME: this code should not be here, it should be taken into account
  91                                         // either by the event fixing code, or the dojo.position()
  92                                         // FIXME: this code doesn't work on Opera 9.5 Beta
  93                                         ry += dojo.body().scrollTop;
  94                                 }
  95                                 dy = 0;
  96                                 if(ry > 0 && ry < b.h){
  97                                         if(ry < h){
  98                                                 dy = -h;
  99                                         }else if(ry > b.h - h){
 100                                                 dy = h;
 101                                         }
 102                                         oldTop = n.scrollTop;
 103                                         n.scrollTop  = n.scrollTop  + dy;
 104                                 }
 105                         }
 106                         if(dx || dy){ return; }
 107                 }
 108                 try{
 109                         n = n.parentNode;
 110                 }catch(x){
 111                         n = null;
 112                 }
 113         }
 114         dojo.dnd.autoScroll(e);
 115 };
 116
 117         return dojo.dnd;
 118 });